# Temperature conversion

Temperature conversion
You are encouraged to solve this task according to the task description, using any language you may know.

There are quite a number of temperature scales. For this task we will concentrate on four of the perhaps best-known ones: Kelvin, Celsius, Fahrenheit, and Rankine.

The Celsius and Kelvin scales have the same magnitude, but different null points.

0 degrees Celsius corresponds to 273.15 kelvin.
0 kelvin is absolute zero.

The Fahrenheit and Rankine scales also have the same magnitude, but different null points.

0 degrees Fahrenheit corresponds to 459.67 degrees Rankine.
0 degrees Rankine is absolute zero.

The Celsius/Kelvin and Fahrenheit/Rankine scales have a ratio of 5 : 9.

Write code that accepts a value of kelvin, converts it to values of the three other scales, and prints the result.

Example
K  21.00

C  -252.15

F  -421.87

R  37.80

## 360 Assembly

Translation of: AWK

Use of packed decimal arithmetic (ZAP,SP,MP,DP,UNPK,CVD,EDMK opcodes).

*        Temperature conversion    10/09/2015
TEMPERAT CSECT
USING TEMPERAT,R15
LA R4,1 i=1
LA R5,TT @tt(1)
LA R6,IDE @ide(1)
LOOPI CH R4,=AL2((T-TT)/8) do i=1 to hbound(tt)
BH ELOOPI
ZAP T,0(8,R5) t=tt(i)
CVD R4,DW store to packed decimal
UNPK PG(1),DW+7(1) unpack
OI PG,X'F0' zap sign
MVI PG+1,C' '
MVC PG+2(12),0(R6) ide(i)
XPRNT PG,14 output i
MVC PG(12),=C'Kelvin: '
EDMK ZN,T+5 t (PL3)
BCTR R1,0 sign location
MVC 0(1,R1),ZN+L'ZN-1 put sign
MVC PG+12(L'ZN-1),ZN value
MVC PG+19(2),=C' K' unit
XPRNT PG,21 output Kelvin
MVC PG(12),=C'Celsius: '
ZAP DW,T t
SP DW,=P'273.15' t-273.15
EDMK ZN,DW+5 (PL3)
BCTR R1,0 sign location
MVC 0(1,R1),ZN+L'ZN-1 put sign
MVC PG+12(L'ZN-1),ZN value
MVC PG+19(2),=C' C' unit
XPRNT PG,21 output Celsius
MVC PG(12),=C'Fahrenheit: '
ZAP DW,T t
MP DW,=P'18' *18
DP DW,=PL3'10' /10
ZAP DW,DW(5)
SP DW,=P'459.67' t*1.8-459.67
EDMK ZN,DW+5 (PL3)
BCTR R1,0 sign location
MVC 0(1,R1),ZN+L'ZN-1 put sign
MVC PG+12(L'ZN-1),ZN value
MVC PG+19(2),=C' F' unit
XPRNT PG,21 output Fahrenheit
MVC PG(12),=C'Rankine: '
ZAP DW,T t
MP DW,=P'18' *18
DP DW,=PL3'10' /10
ZAP DW,DW(5) t*1.8
EDMK ZN,DW+5 (PL3)
BCTR R1,0 sign location
MVC 0(1,R1),ZN+L'ZN-1 put sign
MVC PG+12(L'ZN-1),ZN value
MVC PG+19(2),=C' R' unit
XPRNT PG,21 output Rankine
LA R4,1(R4) i=i+1
LA R5,8(R5) @tt(i)
LA R6,12(R6) @ide(i)
B LOOPI
ELOOPI XR R15,R15
BR R14
IDE DC CL12'absolute',CL12'ice melts',CL12'water boils'
TT DC PL8'0.00',PL8'273.15',PL8'373.15'
T DS PL8
PG DS CL24
ZN DS ZL8 5num
DW DS D PL8 15num
YREGS
END TEMPERAT
Output:
1 absolute
Kelvin:        0.00 K
Celsius:    -273.15 C
Fahrenheit: -459.67 F
Rankine:       0.00 R
2 ice melts
Kelvin:      273.15 K
Celsius:       0.00 C
Fahrenheit:   32.00 F
Rankine:     491.67 R
3 water boils
Kelvin:      373.15 K
Celsius:     100.00 C
Fahrenheit:  212.00 F
Rankine:     671.67 R

## 8th

: KtoC \ n -- n
273.15 n:-
;

: KtoF \ n -- n
1.8 n:* 459.67 n:-
;

: KtoR \ n -- n
1.8 n:*
;

: KtoCFR \ n --
dup dup dup
. " degrees Kelvin" . cr
KtoC
. " degrees Celcius" . cr
KtoF
. " degrees Fahrenheit" . cr
KtoR
. " degrees Rankine" . cr
;

: app:main \
argc 0 n:=
if
"Syntax" . cr " temp.8th number" . cr
else
0 args >n KtoCFR
then
bye
;

Output:
>8th temp.8th 21
21 degrees Kelvin
-252.15000 degrees Celcius
-421.87000 degrees Fahrenheit
37.80000 degrees Rankine

procedure Temperatur_Conversion is
K: Float;
function C return Float is (K - 273.15);
function F return Float is (K * 1.8 - 459.67);
function R return Float is (K * 1.8);
begin
Get(K); New_Line; -- Format
Put("K: "); Put(K, Fore => 4, Aft => 2, Exp => 0); New_Line;-- K: dddd.dd
Put("C: "); Put(C, Fore => 4, Aft => 2, Exp => 0); New_Line;-- C: dddd.dd
Put("F: "); Put(F, Fore => 4, Aft => 2, Exp => 0); New_Line;-- F: dddd.dd
Put("R: "); Put(R, Fore => 4, Aft => 2, Exp => 0); New_Line;-- R: dddd.dd
end;
Output:
21.0

K:   21.00
C: -252.15
F: -421.87
R:   37.80

## Aime

void
show(integer symbol, real temperature)
{
o_form("%c /d2p2w8/\n", symbol, temperature);
}

integer
main(void)
{
real k;

k = atof(argv(1));

show('K', k);
show('C', k - 273.15);
show('F', k * 1.8 - 459.67);
show('R', k * 1.8);

return 0;
}
Output:
aime\$ aime -a tmp/tconvert 300
K   300
C    26.85
F    80.32
R   540

## ALGOL 68

BEGIN
REAL kelvin;
FORMAT f = \$g(8,2), " K = ", g(8,2)xgl\$;
printf ((f, kelvin, kelvin - 273.15, "C"));
printf ((f, kelvin, 9.0 * kelvin / 5.0, "R"));
printf ((f, kelvin, 9.0 * kelvin / 5.0 - 459.67, "F"))
END
Output:
\$ echo 21 | a68g Temperature_conversion.a68
+21.00 K =  -252.15 C
+21.00 K =   +37.80 R
+21.00 K =  -421.87 F
\$

## ALGOL-M

If the temperature in Kelvin is a whole number, you should type a decimal point after it (e.g. 290.): 290 with no decimal point will be interpreted as 0.29 rather than 290.0.

BEGIN
DECIMAL K, C, F, R;
WRITE( "Temperature in Kelvin:" );
C := K - 273.15;
F := K * 1.8 - 459.67;
R := K * 1.8;
WRITE( K, " Kelvin is equivalent to" );
WRITE( C, " degrees Celsius" );
WRITE( F, " degrees Fahrenheit" );
WRITE( R, " degrees Rankine" );
END

## APL

Given a temperature in Kelvin, prints the equivalent in Kelvin, Celsius, Fahrenheit, and Rankine (in that order).

CONVERT←{⍵,(⍵-273.15),(R-459.67),(R←⍵×9÷5)}
Output:
CONVERT 21
21 ¯252.15 ¯421.87 37.8

The "high minus" character ¯ is used in APL to mark negative numbers, preventing any possible confusion with - (the subtraction operator).

## AppleScript

Translation of: JavaScript
( ES6 version )
use framework "Foundation" -- Yosemite onwards, for the toLowerCase() function

-- KELVIN TO OTHER SCALE -----------------------------------------------------

-- kelvinAs :: ScaleName -> Num -> Num
on kelvinAs(strOtherScale, n)
heatBabel(n, "Kelvin", strOtherScale)
end kelvinAs

-- MORE GENERAL CONVERSION ---------------------------------------------------

-- heatBabel :: n -> ScaleName -> ScaleName -> Num
on heatBabel(n, strFromScale, strToScale)
set ratio to 9 / 5
set cels to 273.15
set fahr to 459.67

on |λ|(x, strFrom)
if strFrom = "k" then
x as real
else if strFrom = "c" then
x + cels
else if strFrom = "f" then
(fahr + x) * ratio
else
x / ratio
end if
end |λ|
end script

script writing
on |λ|(x, strTo)
if strTo = "k" then
x
else if strTo = "c" then
x - cels
else if strTo = "f" then
(x * ratio) - fahr
else
x * ratio
end if
end |λ|
end script

toLower(text 1 of strFromScale)), ¬
toLower(text 1 of strToScale))
end heatBabel

-- TEST ----------------------------------------------------------------------
on kelvinTranslations(n)
script translations
on |λ|(x)
{x, kelvinAs(x, n)}
end |λ|
end script

map(translations, {"K", "C", "F", "R"})
end kelvinTranslations

on run
script tabbed
on |λ|(x)
intercalate(tab, x)
end |λ|
end script

intercalate(linefeed, map(tabbed, kelvinTranslations(21)))
end run

-- GENERIC FUNCTIONS ---------------------------------------------------------

-- intercalate :: Text -> [Text] -> Text
on intercalate(strText, lstText)
set {dlm, my text item delimiters} to {my text item delimiters, strText}
set strJoined to lstText as text
set my text item delimiters to dlm
return strJoined
end intercalate

-- map :: (a -> b) -> [a] -> [b]
on map(f, xs)
tell mReturn(f)
set lng to length of xs
set lst to {}
repeat with i from 1 to lng
set end of lst to |λ|(item i of xs, i, xs)
end repeat
return lst
end tell
end map

-- Lift 2nd class handler function into 1st class script wrapper
-- mReturn :: Handler -> Script
on mReturn(f)
if class of f is script then
f
else
script
property |λ| : f
end script
end if
end mReturn

-- toLower :: String -> String
on toLower(str)
set ca to current application
((ca's NSString's stringWithString:(str))'s ¬
lowercaseStringWithLocale:(ca's NSLocale's currentLocale())) as text
end toLower
Output:
K    21.0
C    -252.15
F    -421.87
R    37.8

## AutoHotkey

MsgBox, % "Kelvin:`t`t 21.00 K`n"
. "Celsius:`t`t" kelvinToCelsius(21) " C`n"
. "Fahrenheit:`t" kelvinToFahrenheit(21) " F`n"
. "Rankine:`t`t" kelvinToRankine(21) " R`n"

kelvinToCelsius(k)
{
return, round(k - 273.15, 2)
}
kelvinToFahrenheit(k)
{
return, round(k * 1.8 - 459.67, 2)
}
kelvinToRankine(k)
{
return, round(k * 1.8, 2)
}
Output:
Kelvin:          21.00 K
Celsius:       -252.15 C
Fahrenheit:    -421.87 F
Rankine:         37.80 R

## AutoIt

;	### USAGE - TESTING PURPOSES ONLY

Local Const \$_KELVIN = 21
ConsoleWrite("Kelvin: " & \$_KELVIN & @CRLF)
ConsoleWrite("Kelvin: " & Kelvin(21, "C") & @CRLF)
ConsoleWrite("Kelvin: " & Kelvin(21, "F") & @CRLF)
ConsoleWrite("Kelvin: " & Kelvin(21, "R") & @CRLF)

; ### KELVIN TEMPERATURE CONVERSIONS

Func Kelvin(\$degrees, \$conversion)
Select
Case \$conversion = "C"
Return Round(\$degrees - 273.15, 2)
Case \$conversion = "F"
Return Round((\$degrees * 1.8) - 459.67, 2)
Case \$conversion = "R"
Return Round(\$degrees * 1.8, 2)
EndSelect
EndFunc ;==> Kelvin
Output:
Kelvin: 21°
Celsius: -252.15°
Fahrenheit: -421.87°
Rankine: 37.8°

## AWK

"Interactive" version, reading from stdin only:

# syntax: AWK -f TEMPERATURE_CONVERSION.AWK
BEGIN {
while (1) {
printf("\nKelvin degrees? ")
getline K
if (K ~ /^\$/) {
break
}
if (K < 0) {
print("K must be >= 0")
continue
}
printf("K = %.2f\n",K)
printf("C = %.2f\n",K - 273.15)
printf("F = %.2f\n",K * 1.8 - 459.67)
printf("R = %.2f\n",K * 1.8)
}
exit(0)
}

With no such file, or "-" as filename, reading from stdin:

Works with: gawk
BEGINFILE is a gawk-extension
# usage: gawk -f temperature_conversion.awk  input.txt -

BEGIN { print("# Temperature conversion\n") }
BEGINFILE { print "# reading", FILENAME
if( FILENAME=="-" ) print "# Please enter temperature values in K:\n"
}

!NF { exit }

{ print "Input:" \$0 }
\$1<0 { print("K must be >= 0\n"); next }
{ K = 0+\$1
printf("K = %8.2f Kelvin degrees\n",K)
printf("C = %8.2f\n", K - 273.15)
printf("F = %8.2f\n", K * 1.8 - 459.67)
printf("R = %8.2f\n\n",K * 1.8)
}

END { print("# Bye.") }

Input:
the numeric value of the first word in each line is used as input for the conversion
-1
absolute
184
273.15 ice melts
310x
373.15 water boils
1941 Titanium melts

So, "absolute" has a value of 0, and 310x is just 310.

After that file is read and processed, values are read from stdin.
Here entering "333" by hand, and then stopping with an empty input.

Output:
# Temperature conversion

Input:-1
K must be >= 0

Input:absolute
K =     0.00 Kelvin degrees
C =  -273.15
F =  -459.67
R =     0.00

Input:184
K =   184.00 Kelvin degrees
C =   -89.15
F =  -128.47
R =   331.20

Input:273.15 ice melts
K =   273.15 Kelvin degrees
C =     0.00
F =    32.00
R =   491.67

Input:310x
K =   310.00 Kelvin degrees
C =    36.85
F =    98.33
R =   558.00

Input:373.15 water boils
K =   373.15 Kelvin degrees
C =   100.00
F =   212.00
R =   671.67

Input:1941 Titanium melts
K =  1941.00 Kelvin degrees
C =  1667.85
F =  3034.13
R =  3493.80

# Please enter temperature values in K:

Input:333
K =   333.00 Kelvin degrees
C =    59.85
F =   139.73
R =   599.40

# Bye.

## BASIC

10 REM TRANSLATION OF AWK VERSION
20 INPUT "KELVIN DEGREES",K
30 IF K <= 0 THEN END: REM A VALUE OF ZERO OR LESS WILL END PROGRAM
40 LET C = K - 273.15
50 LET F = K * 1.8 - 459.67
60 LET R = K * 1.8
70 PRINT K; " KELVIN IS EQUIVALENT TO"
80 PRINT C; " DEGREES CELSIUS"
90 PRINT F; " DEGREES FAHRENHEIT"
100 PRINT R; " DEGREES RANKINE"
110 GOTO 20

### IS-BASIC

100 INPUT PROMPT "Kelvin degrees: ":K
110 PRINT K;TAB(10);"Kelvin is equivalent to"
120 PRINT K-273.15;TAB(10);"Degrees Celsius"
130 PRINT K*1.8-459.67;TAB(10);"Degrees Fahrenheit"
140 PRINT K*1.8;TAB(10);"Degrees Rankine"

### Sinclair ZX81 BASIC

10 PRINT "ENTER A TEMPERATURE IN KELVINS"
20 INPUT K
30 PRINT K;" KELVINS ="
40 PRINT K-273.15;" DEGREES CELSIUS"
50 PRINT K*1.8-459.67;" DEGREES FAHRENHEIT"
60 PRINT K*1.8;" DEGREES RANKINE"

## BASIC256

do
print "Kelvin degrees (>=0): ";
input K
until K>=0

print "K = " + string(K)
print "C = " + string(K - 273.15)
print "F = " + string(K * 1.8 - 459.67)
print "R = " + string(K * 1.8)

## BBC BASIC

REPEAT
INPUT "Kelvin degrees (>=0): " K
UNTIL K>=0
@%=&20208
PRINT '"K = " K
PRINT "C = " K - 273.15
PRINT "F = " K * 1.8 - 459.67
PRINT "R = " K * 1.8
END

Output:
Kelvin degrees (>=0): 21

K =    21.00
C =  -252.15
F =  -421.87
R =    37.80

## Befunge

The temperature to convert is read from stdin. Befunge has no support for real numbers, though, so reading and writing of decimal values is done with character I/O. For the same reason, the temperature calculations use integer arithmetic to emulate fixed point. The first two lines handle the input; the second line performs the conversion calculations; and the last three handle the output.

0000>0p~>"."-:!#v_2-::0\`\9`+!#v_\$1>/\:3`#v_\>\:3 \`#v_v
1#<<^0 /2++g001!<1 \+g00\+*+55\< ^+55\-1< ^*+55\+1<v_
"K"\-+**"!Y]"9:\"C"\--\**"^CIT"/5*9:\"F"\/5*9:\"R"\0\0<v
v/+55\+*86%+55: /+55\+*86%+55: \0/+55+5*-\1*2 p00:`\0:,<
>"."\>:55+% 68*v >:#,_\$55+,\:!#@_^
\$_^#!:/+55\+< ^\" :"_<g00*95
Output:
21
K: 21.00
C: -252.15
F: -421.87
R: 37.80

## Bracmat

( ( rational2fixedpoint
= minus fixedpointnumber number decimals
.  !arg:(#?number.~<0:~/#?decimals)
& ( !number:0&"0.0"
| ( !number:>0&
| -1*!number:?number&"-"
)
: ?minus
& !number+1/2*10^(-1*!decimals):?number
& !minus div\$(!number.1) ".":?fixedpointnumber
& whl
' ( !decimals+-1:~<0:?decimals
&  !fixedpointnumber
div\$(mod\$(!number.1)*10:?number.1)
: ?fixedpointnumber
)
& str\$!fixedpointnumber
)
)
& ( fixedpoint2rational
= integerpart fractionalpart decimals
. @( !arg
: #?integerpart
( "." ?fractionalpart
| &0:?fractionalpart
)
)
& @(!fractionalpart:? #?fractionalpart [?decimals)
&  !integerpart
+ (!integerpart:<0&-1|1)
* 10^(-1*!decimals)
* !fractionalpart
)
& whl
' ( put\$"Enter Kelvin temperature:"
& fixedpoint2rational\$(get'(,STR)):?kelvin
& !kelvin+-27315/100:?celcius
& (degree=.str\$(chu\$(x2d\$b0) !arg))
& out\$(rational2fixedpoint\$(!kelvin.2) K)
& out\$(rational2fixedpoint\$(!celcius.2) degree\$C)
& out\$(rational2fixedpoint\$(!celcius*9/5+32.2) degree\$F)
& out\$(rational2fixedpoint\$(!kelvin*9/5.2) degree\$Ra)
& out\$(rational2fixedpoint\$(!celcius*4/5.2) degree\$Ré)
)
& done!
)
Output:
Enter Kelvin temperature:21.00
21.00 K
-252.15 °C
-421.87 °F
37.80 °Ra
-201.72 °Ré

## C

#include <stdio.h>
#include <stdlib.h>

double kelvinToCelsius(double k){
return k - 273.15;
}

double kelvinToFahrenheit(double k){
return k * 1.8 - 459.67;
}

double kelvinToRankine(double k){
return k * 1.8;
}
void convertKelvin(double kelvin) {
printf("K %.2f\n", kelvin);
printf("C %.2f\n", kelvinToCelsius(kelvin));
printf("F %.2f\n", kelvinToFahrenheit(kelvin));
printf("R %.2f", kelvinToRankine(kelvin));
}

int main(int argc, const char * argv[])
{
if (argc > 1) {
double kelvin = atof(argv[1]);
convertKelvin(kelvin);
}
return 0;
}

## C++

#include <iostream>
#include <iomanip>

//--------------------------------------------------------------------------------------------------
using namespace std;

//--------------------------------------------------------------------------------------------------
class converter
{
public:
converter() : KTC( 273.15f ), KTDel( 3.0f / 2.0f ), KTF( 9.0f / 5.0f ), KTNew( 33.0f / 100.0f ),
KTRank( 9.0f / 5.0f ), KTRe( 4.0f / 5.0f ), KTRom( 21.0f / 40.0f ) {}

void convert( float kelvin )
{
float cel = kelvin - KTC,
del = ( 373.15f - kelvin ) * KTDel,
fah = kelvin * KTF - 459.67f,
net = cel * KTNew,
rnk = kelvin * KTRank,
rea = cel * KTRe,
rom = cel * KTRom + 7.5f;

cout << endl << left
<< "TEMPERATURES:" << endl
<< "===============" << endl << setw( 13 )
<< "CELSIUS:" << cel << endl << setw( 13 )
<< "DELISLE:" << del << endl << setw( 13 )
<< "FAHRENHEIT:" << fah << endl << setw( 13 )
<< "KELVIN:" << kelvin << endl << setw( 13 )
<< "NEWTON:" << net << endl << setw( 13 )
<< "RANKINE:" << rnk << endl << setw( 13 )
<< "REAUMUR:" << rea << endl << setw( 13 )
<< "ROMER:" << rom << endl << endl << endl;
}
private:
const float KTRank, KTC, KTF, KTRe, KTDel, KTNew, KTRom;
};
//--------------------------------------------------------------------------------------------------
int main( int argc, char* argv[] )
{
converter con;
float k;
while( true )
{
cout << "Enter the temperature in Kelvin to convert: ";
cin >> k;
con.convert( k );
system( "pause" );
system( "cls" );
}
return 0;
}
//--------------------------------------------------------------------------------------------------

Output:
Enter the temperature in Kelvin to convert: 373.15

TEMPERATURES:
===============
CELSIUS:     100
DELISLE:     0
FAHRENHEIT:  212
KELVIN:      373.15
NEWTON:      33
RANKINE:     671.67
REAUMUR:     80
ROMER:       60

## C#

using System;

namespace TemperatureConversion
{
class Program
{
static Func<double, double> ConvertKelvinToFahrenheit = x => (x * 1.8) - 459.67;
static Func<double, double> ConvertKelvinToRankine = x => x * 1.8;
static Func<double, double> ConvertKelvinToCelsius = x => x = 273.13;

static void Main(string[] args)
{
Console.Write("Enter a Kelvin Temperature: ");
double kelvinTemp = 0f;

if (double.TryParse(inputVal, out kelvinTemp))
{
Console.WriteLine(string.Format("Kelvin: {0}", kelvinTemp));
Console.WriteLine(string.Format("Fahrenheit: {0}", ConvertKelvinToFahrenheit(kelvinTemp)));
Console.WriteLine(string.Format("Rankine: {0}", ConvertKelvinToRankine(kelvinTemp)));
Console.WriteLine(string.Format("Celsius: {0}", ConvertKelvinToCelsius(kelvinTemp)));
}
else
{
Console.WriteLine("Invalid input value: " + inputVal);
}
}
}
}
Enter a Kelvin Temperature: 21
Kelvin: 21
Fahrenheit: -421.87
Rankine: 37.8
Celsius: 273.13

## Ceylon

shared void run() {

void printKelvinConversions(Float kelvin) {
value celsius = kelvin - 273.15;
value rankine = kelvin * 9.0 / 5.0;
value fahrenheit = rankine - 459.67;

print("Kelvin: ``formatFloat(kelvin, 2, 2)``
Celsius: ``formatFloat(celsius, 2, 2)``
Fahrenheit: ``formatFloat(fahrenheit, 2, 2)``
Rankine: ``formatFloat(rankine, 2, 2)``");
}

printKelvinConversions(21.0);

}

## Clojure

Translation of: Common Lisp
(defn to-celsius [k]
(- k 273.15))
(defn to-fahrenheit [k]
(- (* k 1.8) 459.67))
(defn to-rankine [k]
(* k 1.8))

(defn temperature-conversion [k]
(if (number? k)
(format "Celsius: %.2f Fahrenheit: %.2f Rankine: %.2f"
(to-celsius k) (to-fahrenheit k) (to-rankine k))
(format "Error: Non-numeric value entered.")))
Output:
user=> (temperature-conversion 21.0)
"Celsius: -252.15 Fahrenheit: -421.87 Rankine: 37.80"

## COBOL

Works with: Visual COBOL
IDENTIFICATION DIVISION.
PROGRAM-ID. temp-conversion.

DATA DIVISION.
WORKING-STORAGE SECTION.
78 Kelvin-Rankine-Ratio VALUE 0.5556. *> 5 / 9 to 4 d.p.
78 Kelvin-Celsius-Diff VALUE 273.15.
78 Rankine-Fahrenheit-Diff VALUE 459.67.

01 temp-kelvin PIC S9(8)V99.
01 temp-rankine PIC S9(8)V99.

01 kelvin PIC -(7)9.99.
01 celsius PIC -(7)9.99.
01 rankine PIC -(7)9.99.
01 fahrenheit PIC -(7)9.99.

PROCEDURE DIVISION.
DISPLAY "Enter a temperature in Kelvin to convert: " NO ADVANCING
ACCEPT temp-kelvin

MOVE temp-kelvin TO kelvin
DISPLAY "K " kelvin

SUBTRACT Kelvin-Celsius-Diff FROM temp-kelvin GIVING celsius
DISPLAY "C " celsius

DIVIDE temp-kelvin BY Kelvin-Rankine-Ratio
GIVING temp-rankine, rankine
SUBTRACT Rankine-Fahrenheit-Diff FROM temp-rankine GIVING fahrenheit

DISPLAY "F " fahrenheit
DISPLAY "R " rankine

GOBACK
.
Output:
Enter a temperature in Kelvin to convert: 21
K       21.00
C     -252.15
F     -421.88
R       37.79

## Common Lisp

Three functions define the necessary conversion formulas. A fancy format string is used to print these values.

(defun to-celsius (k)
(- k 273.15))
(defun to-fahrenheit (k)
(- (* k 1.8) 459.67))
(defun to-rankine (k)
(* k 1.8))

(defun temperature-conversion ()
(if (numberp k)
(format t "Celsius: ~d~%Fahrenheit: ~d~%Rankine: ~d~%"
(to-celsius k) (to-fahrenheit k) (to-rankine k))
(format t "Error: Non-numeric value entered."))))

Output:
* (temperature-conversion)
21
Celsius: -252.15
Fahrenheit: -421.87003
Rankine: 37.8
NIL

## D

double kelvinToCelsius(in double k) pure nothrow @safe {
return k - 273.15;
}

double kelvinToFahrenheit(in double k) pure nothrow @safe {
return k * 1.8 - 459.67;
}

double kelvinToRankine(in double k) pure nothrow @safe {
return k * 1.8;
}

unittest {
import std.math: approxEqual;
assert(approxEqual(kelvinToCelsius(21.0), -252.15));
assert(approxEqual(kelvinToFahrenheit(21.0), -421.87));
assert(approxEqual(kelvinToRankine(21.0), 37.8));
}

void main(string[] args) {
import std.stdio, std.conv, std.string;

if (args.length == 2 && isNumeric(args[1])) {
immutable kelvin = to!double(args[1]);
if (kelvin >= 0) {
writefln("K  %2.2f", kelvin);
writefln("C  %2.2f", kelvinToCelsius(kelvin));
writefln("F  %2.2f", kelvinToFahrenheit(kelvin));
writefln("R  %2.2f", kelvinToRankine(kelvin));
} else
writefln("%2.2f K is below absolute zero", kelvin);
}
}
Output:
K  21.00

C  -252.15

F  -421.87

R  37.80

## Delphi

program Temperature;

{\$APPTYPE CONSOLE}

uses
SysUtils;

type
TTemp = class
private
fCelsius, fFahrenheit, fRankine: double;
public
constructor Create(aKelvin: double);
end;

{ TTemp }

constructor TTemp.Create(aKelvin: double);
begin
fCelsius := aKelvin - 273.15;
fRankine := aKelvin * 9 / 5;
fFahrenheit := fRankine - 459.67;
end;

var
kelvin: double;
temp: TTemp;

begin
write('Kelvin: ');
temp := TTemp.Create(kelvin);
writeln(Format('Celsius: %.2f', [temp.AsCelsius]));
writeln(Format('Fahrenheit: %.2f', [temp.AsFahrenheit]));
writeln(Format('Rankine: %.2f', [temp.AsRankine]));
temp.Free;
end.

Output:
Kelvin: 21.00
Celsius: -252.15
F: -421.87
R: 37.80

## Elena

ELENA 3.4 :

import extensions.

convertKelvinToFahrenheit = (:x)(x * 1.8r - 459.6r).
convertKelvinToRankine = (:x)(x * 1.8r).
convertKelvinToCelsius = (:x)(x - 273.15r).

public program
[
console print("Enter a Kelvin Temperature: ").
real kelvinTemp := 0.0r.
try(realConvertor convert(inputVal, &qkelvinTemp))
{
on(Exception e)
[
console printLine("Invalid input value: ", inputVal).

AbortException new; raise
]
}.

console printLine("Kelvin: ", kelvinTemp).
console printLine("Fahrenheit: ", convertKelvinToFahrenheit(kelvinTemp)).
console printLine("Rankine: ", convertKelvinToRankine(kelvinTemp)).
console printLine("Celsius: ", convertKelvinToCelsius(kelvinTemp)).
]
Output:
Enter a Kelvin Temperature: 21
Kelvin: 21.0
Fahrenheit: -421.87
Rankine: 37.8
Celsius: -252.15

## Elixir

defmodule Temperature do
def conversion(t) do
IO.puts "K : #{f(t)}"
IO.puts "\nC : #{f(t - 273.15)}"
IO.puts "\nF : #{f(t * 1.8 - 459.67)}"
IO.puts "\nR : #{f(t * 1.8)}"
end

defp f(a) do
Float.round(a, 2)
end

end

Output:
K : 21.0

C : -252.15

F : -421.87

R : 37.8

## Erlang

% Implemented by Arjun Sunel
-module(temp_conv).
-export([main/0]).

main() ->
conversion(21).

conversion(T) ->
io:format("\nK : ~p\n\n",[f(T)]),
io:format("C : ~p \n\n",[f(T - 273.15)]),
io:format("F : ~p\n\n",[f(T * 1.8 - 459.67)]),
io:format("R : ~p\n\n",[f(T * 1.8)]).

f(A) ->
(round(A*100))/100 .

Output:
K : 21.0

C : -252.15

F : -421.87

R : 37.8

ok

## Euphoria

include std/console.e

atom K
while 1 do
K = prompt_number("Enter temperature in Kelvin >=0: ",{0,4294967296})
printf(1,"K = %5.2f\nC = %5.2f\nF = %5.2f\nR = %5.2f\n\n",{K,K-273.15,K*1.8-459.67,K*1.8})
end while

Output:
Enter temperature in Kelvin >=0: 21
K = 21.00
C = -252.15
F = -421.87
R = 37.80

Enter temperature in Kelvin >=0:

## Excel

A1 : Kelvin
B1 : Celsius
C1 : Fahrenheit
D1 : Rankine
Name A2 : K
B2 : =K-273.15
C2 : =K*1.8-459.67
D2 : =K*1.8
Input in A1
Output:
A          B          C          D
1 Kelvin     Celsius    Fahrenheit Rankine
2         21    -252.15    -421.87       37.8

## Ezhil

# convert from Kelvin
நிரல்பாகம் கெல்வின்_இருந்து_மாற்று( k )
பதிப்பி "Kelvin: ",k,"Celsius: ",round(k-273.15)," Fahrenheit: ",(round(k*1.8 - 459.67))," Rankine: ",(round(k*1.8))
முடி

கெல்வின்_இருந்து_மாற்று( 0 ) #absolute zero
கெல்வின்_இருந்து_மாற்று( 273 ) #freezing pt of water
கெல்வின்_இருந்து_மாற்று( 30 + 273 ) #room temperature in Summer

## F#

// Define units of measure
[<Measure>] type k
[<Measure>] type f
[<Measure>] type c
[<Measure>] type r

// Define conversion functions
let kelvinToCelsius (t : float<k>) = ((float t) - 273.15) * 1.0<c>
let kelvinToFahrenheit (t : float<k>) = (((float t) * 1.8) - 459.67) * 1.0<f>
let kelvinToRankine (t : float<k>) = ((float t) * 1.8) * 1.0<r>

// Example code
let K = 21.0<k>
printfn "%A Kelvin is %A Celsius" K (kelvinToCelsius K)
printfn "%A Kelvin is %A Fahrenheit" K (kelvinToFahrenheit K)
printfn "%A Kelvin is %A Rankine" K (kelvinToRankine K)

## Factor

USING: combinators formatting kernel math ;
IN: rosetta-code.temperature

: k>c ( kelvin -- celsius ) 273.15 - ;
: k>r ( kelvin -- rankine ) 9/5 * ;
: k>f ( kelvin -- fahrenheit ) k>r 459.67 - ;

: convert ( kelvin -- )
{ [ ] [ k>c ] [ k>f ] [ k>r ] } cleave
"K  %.2f\nC  %.2f\nF  %.2f\nR  %.2f\n" printf ;

21 convert
Output:
K  21.00
C  -252.15
F  -421.87
R  37.80

## FOCAL

01.10 ASK "TEMPERATURE IN KELVIN", K
01.20 TYPE "K ", %6.02, K, !
01.30 TYPE "C ", %6.02, K - 273.15, !
01.40 TYPE "F ", %6.02, K * 1.8 - 459.67, !
01.50 TYPE "R ", %6.02, K * 1.8, !
Output:
TEMPERATURE IN KELVIN:373.15
K =  373.15
C =  100.00
F =  212.00
R =  671.67

## Forth

Works with: GNU Forth
for the command line handling
: k>°C  ( F: kelvin  -- celsius )     273.15e0 f- ;
: k>°R ( F: kelvin -- rankine ) 1.8e0 f* ;
: °R>°F ( F: rankine -- fahrenheit ) 459.67e0 f- ;
: k>°F ( F: kelvin -- fahrenheit ) k>°R °R>°F ;
: main
argc 1 > if 1 arg >float
fdup f. ." K" cr
fdup k>°C f. ." °C" cr
fdup k>°F f. ." °F" cr
fdup k>°R f. ." °R" cr
then ;

main bye
Output:
> gforthamd64 rosetta_temp_conv.fs 21
21. K
-252.15 °C
-421.87 °F
37.8 °R

## Fortran

Works with: Fortran version 90 and later
Program Temperature
implicit none

real :: kel, cel, fah, ran

write(*,*) "Input Kelvin temperature to convert"

call temp_convert(kel, cel, fah, ran)
write(*, "((a10), f10.3)") "Kelvin", kel
write(*, "((a10), f10.3)") "Celsius", cel
write(*, "((a10), f10.3)") "Fahrenheit", fah
write(*, "((a10), f10.3)") "Rankine", ran

contains

subroutine temp_convert(kelvin, celsius, fahrenheit, rankine)
real, intent(in) :: kelvin
real, intent(out) :: celsius, fahrenheit, rankine

celsius = kelvin - 273.15
fahrenheit = kelvin * 1.8 - 459.67
rankine = kelvin * 1.8

end subroutine
end program

## FreeBASIC

' FB 1.05.0 Win64

Sub convKelvin(temp As Double)
Dim f As String = "####.##"
Print Using f; temp;
Print " degrees Kelvin"
Print Using f; temp - 273.15;
Print " degrees Celsius"
Print Using f; (temp - 273.15) * 1.8 + 32.0;
Print " degrees Fahreneit"
Print Using f; (temp - 273.15) * 1.8 + 32.0 + 459.67;
Print " degrees Rankine"
End Sub

convKelvin(0.0)
Print
convKelvin(21.0)
Print
Print "Press any key to quit"
Sleep
Output:
0.00 degrees Kelvin
-273.15 degrees Celsius
-459.67 degrees Fahreneit
0.00 degrees Rankine

21.00 degrees Kelvin
-252.15 degrees Celsius
-421.87 degrees Fahreneit
37.80 degrees Rankine

## Gambas

Public Sub Form_Open()
Dim fKelvin As Float

fKelvin = InputBox("Enter a Kelvin value", "Kelvin converter")

Print "Kelvin =\t" & Format(Str(fKelvin), "#.00")
Print "Celsius =\t" & Format(Str(fKelvin - 273.15), "#.00")
Print "Fahrenheit =\t" & Format(Str(fKelvin * 1.8 - 459.67), "#.00")
Print "Rankine =\t" & Format(Str(fKelvin * 1.8), "#.00")

End

Output:

Kelvin =        21.00
Celsius =       -252.15
Fahrenheit =    -421.87
Rankine =       37.80

## Go

package main

import (
"fmt"
"os"
"strconv"
)

func main() {
if len(os.Args) != 2 {
fmt.Println("Usage: k <Kelvin>")
return
}
k, err := strconv.ParseFloat(os.Args[1], 64)
if err != nil {
fmt.Println(err)
return
}
if k < 0 {
fmt.Println("Kelvin must be >= 0.")
return
}
fmt.Printf("K  %.2f\n", k)
fmt.Printf("C  %.2f\n", k-273.15)
fmt.Printf("F  %.2f\n", k*9/5-459.67)
fmt.Printf("R  %.2f\n", k*9/5)
}
Output:
> k 21
K  21.00
C  -252.15
F  -421.87
R  37.80

## Groovy

class Convert{
static void main(String[] args){
def c=21.0;
println("K "+c)
println("C "+k_to_c(c));
println("F "+k_to_f(k_to_c(c)));
println("R "+k_to_r(c));
}
static def k_to_c(def k=21.0){return k-273.15;}
static def k_to_f(def k=21.0){return ((k*9)/5)+32;}
static def k_to_r(def k=21.0){return k*1.8;}
}

Output:
K 21.0
C -252.15
F -421.87
R 37.80

import System.Exit (die)

main = do
putStrLn "Please enter temperature in kelvin: "
input <- getLine
if kelvin < 0.0
then die "Temp cannot be negative"
else mapM_ putStrLn \$ convert kelvin

convert :: Double -> [String]
convert n = zipWith (++) labels nums
where labels = ["kelvin: ", "celcius: ", "farenheit: ", "rankine: "]
conversions = [id, subtract 273, subtract 459.67 . (1.8 *), (*1.8)]
nums = (show . (\$n)) <\$> conversions

Or with properly managed exceptions:

{-# LANGUAGE LambdaCase #-}

import System.Exit (die)

main = putStrLn "Please enter temperature in kelvin: " >>
runExceptT getTemp >>=
\case Right x -> mapM_ putStrLn \$ convert x
Left err -> die err

convert :: Double -> [String]
convert n = zipWith (++) labels nums
where labels = ["kelvin: ", "celcius: ", "farenheit: ", "rankine: "]
conversions = [id, subtract 273, subtract 459.67 . (1.8 *), (1.8 *)]
nums = (show . (\$ n)) <\$> conversions

getTemp :: ExceptT String IO Double
getTemp = do
tryAssert "Temp cannot be negative" (t>=0)
return t

## Icon and Unicon

The following program works in both languages:

procedure main(A)
k := A[1] | 21.00
write("K ",k)
write("C ",k-273.15)
write("R ",r := k*(9.0/5.0))
write("F ",r - 459.67)
end

Sample runs:

->tc
K 21.0
C -252.15
R 37.8
F -421.87
->tc 273.15
K 273.15
C 0.0
R 491.67
F 32.0
->

## J

Solution:
NB.  Temp conversions are all linear polynomials
K2K =: 0 1 NB. K = (1 *k) + 0
K2C =: _273 1 NB. C = (1 *k) - 273
K2F =: _459.67 1.8 NB. F = (1.8*k) - 459.67
K2R =: 0 1.8 NB. R = (1.8*k) + 0

NB. Do all conversions at once (eval
NB. polynomials in parallel). This is the
NB. numeric matrix J programs would manipulate
NB. directly.
k2KCFR =: (K2K , K2C , K2F ,: K2R) p./ ]
Example:
NB. Format matrix for printing & tag each
NB. temp with scale, for human legibility
fmt =: [: (;:inv"1) 0 _1 |: 'KCFR' ;"0 1"_1 '0.2' 8!:0 ]
kcfr =: [email protected]

kcfr 21
K 21.00
C -252.00
F -421.87
R 37.80

kcfr 0 NB. Absolute zero
K 0.00
C -273.00
F -459.67
R 0.00

kcfr 21 100 300 NB. List of temps works fine
K 21.00 100.00 300.00
C -252.00 -173.00 27.00
F -421.87 -279.67 80.33
R 37.80 180.00 540.00

Notes: The approach is founded on polynomials, one for each conversion (e.g. Fahrenheit = 1.8*x - 459.67 where x is measured in degrees Kelvin), and all polynomials are evaluated simultaneously using the built-in p.. Through some code decorations (specifically the / in p./ the "0 1"_1 and the 0 _1 |:), we permit our function to convert arrays of temperatures of arbitrarily high dimension (a single temp, lists of temps, tables of temps, cubes of temps, etc).

## Java

public class TemperatureConversion {
public static void main(String args[]) {
if (args.length == 1) {
try {
double kelvin = Double.parseDouble(args[0]);
if (kelvin >= 0) {
System.out.printf("K  %2.2f\n", kelvin);
System.out.printf("C  %2.2f\n", kelvinToCelsius(kelvin));
System.out.printf("F  %2.2f\n", kelvinToFahrenheit(kelvin));
System.out.printf("R  %2.2f\n", kelvinToRankine(kelvin));
} else {
System.out.printf("%2.2f K is below absolute zero", kelvin);
}
} catch (NumberFormatException e) {
System.out.println(e);
}
}
}

public static double kelvinToCelsius(double k) {
return k + 273.15;
}

public static double kelvinToFahrenheit(double k) {
return k * 1.8 - 459.67;
}

public static double kelvinToRankine(double k) {
return k * 1.8;
}
}
Output:
K  21.00

C  -252.15

F  -421.87

R  37.80

## JavaScript

### ES5

var k2c = k => k - 273.15
var k2r = k => k * 1.8
var k2f = k => k2r(k) - 459.67

Number.prototype.toMaxDecimal = function (d) {
return +this.toFixed(d) + ''
}

function kCnv(k) {
document.write( k,'K° = ', k2c(k).toMaxDecimal(2),'C° = ', k2r(k).toMaxDecimal(2),'R° = ', k2f(k).toMaxDecimal(2),'F°<br>' )
}

kCnv(21)
kCnv(295)
Output:
21K° = -252.15C° = 37.8R° = -421.87F°
295K° = 21.85C° = 531R° = 71.33F°

### ES6

Deriving kelvinTranslations() from a more general heatBabel() function.

(() => {
'use strict';

let kelvinTranslations = k => ['K', 'C', 'F', 'R']
.map(x => [x, heatBabel(k, 'K', x)]);

// heatBabel :: Num -> ScaleName -> ScaleName -> Num
let heatBabel = (n, strFromScale, strToScale) => {
let ratio = 9 / 5,
cels = 273.15,
fahr = 459.67,
id = x => x,
k: id,
c: x => cels + x,
f: x => (fahr + x) * ratio,
r: x => x / ratio
},
writeK = {
k: id,
c: x => x - cels,
f: x => (x * ratio) - fahr,
r: x => ratio * x
};

return writeK[strToScale.charAt(0).toLowerCase()](
).toFixed(2);
};

// TEST
return kelvinTranslations(21)
.map(([s, n]) => s + (' ' + n)
.slice(-10))
.join('\n');

})();

Output:
K     21.00
C   -252.15
F   -421.87
R     37.80

## jq

The hard part here is defining round/1 generically.

# round(keep) takes as input any jq (i.e. JSON) number and emits a string.
# "keep" is the desired maximum number of numerals after the decimal point,
# e.g. 9.999|round(2) => 10.00
def round(keep):
tostring
| (index("e") | if . then . else index("E") end) as \$e
| if \$e then (.[0:\$e] | round(keep)) + .[\$e+1:]
else index(".") as \$ix
| if \$ix == null then .
else .[0:\$ix + 1] as \$head
| .[\$ix+1:\$ix+keep+2] as \$tail
| if (\$tail|length) <= keep then \$head + \$tail
else (\$tail | .[length-1:] | tonumber) as \$last
| if \$last < 5 then \$head + \$tail[0:\$tail|length - 1]
else ((\$head + \$tail) | length) as \$length
| (tonumber + (if \$head[0:1]=="-" then -5 else 5 end))
| tostring
| .[0: (\$ix+1+length-\$length)] + "." + .[length-keep-1:-1]
end
end
end
end;

def k2c: . - 273.15;
def k2f: . * 1.8 - 459.67;
def k2r: . * 1.8;

# produce a stream
def cfr:
if . >= 0
then "Kelvin: \(.)", "Celsius: \(k2c|round(2))",
"Fahrenheit: \(k2f|round(2))", "Rankine: \(k2r|round(2))"
else error("cfr: \(.) is an invalid temperature in degrees Kelvin")
end;

cfr

Example

\$ jq -M -r -f Temperature_conversion.jq
21
Kelvin: 21
Celsius: -252.15
Fahrenheit: -421.87
Rankine: 37.80

-1
jq: error: cfr: -1 is an invalid temperature in degrees Kelvin

## Julia

cfr(k) = print("Kelvin: \$k, ",
"Celsius: \$(round(k-273.15,2)), ",
"Fahrenheit: \$(round(k*1.8-459.67,2)), ",
"Rankine: \$(round(k*1.8,2))")
julia> cfr(21)
Kelvin: 21, Celsius: -252.15, Fahrenheit: -421.87, Rankine: 37.8

## Kotlin

// version 1.1.2

class Kelvin(val degrees: Double) {
fun toCelsius() = degrees - 273.15

fun toFahreneit() = (degrees - 273.15) * 1.8 + 32.0

fun toRankine() = (degrees - 273.15) * 1.8 + 32.0 + 459.67
}

fun main(args: Array<String>) {
print("Enter the temperature in degrees Kelvin : ")
val k = Kelvin(degrees)
val f = "% 1.2f"
println()
println("K \${f.format(k.degrees)}\n")
println("C \${f.format(k.toCelsius())}\n")
println("F \${f.format(k.toFahreneit())}\n")
println("R \${f.format(k.toRankine())}")
}
Output:
Enter the temperature in degrees Kelvin : 21

K   21.00

C  -252.15

F  -421.87

R   37.80

## Lasso

define tempconverter(temp, kind) => {

local(
_temp = decimal(#temp),
convertratio = 1.8,
k_c = 273.15,
r_f = 459.67,
k,c,r,f
)

match(#kind) => {
case('k')
#k = #_temp
#c = -#k_c + #k
#r = #k * #convertratio
#f = -#r_f + #r
case('c')
#c = #_temp
#k = #k_c + #c
#r = #k * #convertratio
#f = -#r_f + #r
case('r')
#r = #_temp
#f = -#r_f + #r
#k = #r / #convertratio
#c = -#k_c + #k
case('f')
#f = #_temp
#r = #r_f + #f
#k = #r / #convertratio
#c = -#k_c + #k
case
return 'Something wrong'
}

return ('K = ' + #k -> asstring(-precision = 2) +
' C = ' + #c -> asstring(-precision = 2) +
' R = ' + #r -> asstring(-precision = 2) +
' F = ' + #f -> asstring(-precision = 2)
)
}

tempconverter(21, 'k')
'<br />'
tempconverter(21, 'c')
'<br />'
tempconverter(-41, 'c')
'<br />'
tempconverter(37.80, 'r')
'<br />'
tempconverter(69.80, 'f')
K = 21.00 C = -252.15 R = 37.80 F = -421.87
K = 294.15 C = 21.00 R = 529.47 F = 69.80
K = 232.15 C = -41.00 R = 417.87 F = -41.80
K = 21.00 C = -252.15 R = 37.80 F = -421.87
K = 294.15 C = 21.00 R = 529.47 F = 69.80

## LiveCode

function convertDegrees k
put k/5 * 9 into r
put k - 273.15 into c
put r - 459.67 into f
return k,r,c,f
end convertDegrees
Example
put convertDegrees(21.00) into tTemp
put item 1 of tTemp into temperature["Kelvin"]
put item 2 of tTemp into temperature["Rankine"]
put item 3 of tTemp into temperature["Celsius"]
put item 4 of tTemp into temperature["Fahrenheit"]
combine temperature using comma and colon
put temperature

-- Celsius:-252.15,Fahrenheit:-421.87,Kelvin:21.00,Rankine:37.8

## Lua

function convert_temp(k)
local c = k - 273.15
local r = k * 1.8
local f = r - 459.67
return k, c, r, f
end

print(string.format([[
Kelvin: %.2f K
Celcius: %.2f °C
Rankine: %.2f °R
Fahrenheit: %.2f °F
]],convert_temp(21.0)))

## Maple

tempConvert := proc(k)
seq(printf("%c: %.2f\n", StringTools[UpperCase](substring(i, 1)), convert(k, temperature, kelvin, i)), i in [kelvin, Celsius, Fahrenheit, Rankine]);
return NULL;
end proc:

tempConvert(21);
Output:
K: 21.00
C: -252.15
F: -421.87
R: 37.80

## Mathematica

tempConvert[t_] :=
Grid[[email protected]{{"K", "C", "F", "R"},
Round[{t, t - 273.15, 9 t/5 - 459.67, 9 t/5}, .01]}]

tempConvert[21]
Output:

K 21. C -252.15 F -421.87 R 37.8

## MiniZinc

float: kelvin;

var float: celsius;
var float: fahrenheit;
var float: rankine;

constraint celsius == kelvin - 273.15;
constraint fahrenheit == celsius * 1.8 + 32;
constraint rankine == fahrenheit + 459.67;
solve satisfy;

output ["K \(kelvin)\n", "C \(celsius)\n", "F \(fahrenheit)\n", "R \(rankine)\n"];
Output:

Compiling temperature.mzn, additional arguments kelvin=1000; Running temperature.mzn K 1000.0 C 726.850000000001 F 1340.33 R 1800.0 ---------- Finished in 62msec

## МК-61/52

П7	0	,	8	*	П8	ИП7	9	*	5
/ 3 2 + П9 ИП7 2 7 3 ,
1 5 + П4 С/П П8 1 , 8 /
БП 00 П9 3 2 - 5 * 9 /
БП 00 П4 2 7 3 , 1 5 -
БП 00

Instruction:

tºC = РX В/О С/П;

tºRa = РX БП 25 С/П;

tºF = РX БП 32 С/П;

tK = РX БП 42 С/П;

Result:

РX = Р4 = tK;

Р7 = tºC;

Р8 = tºRa;

Р9 = tºF.

## ML

### mLite

Temperature in Kelvin given on command line.

fun KtoC n = n - 273.15;
fun KtoF n = n * 1.8 - 459.67;
fun KtoR n = n * 1.8;
val K = argv 0;

if K = false then
println "mlite -f temcon.m <temp>"
else
let
val K = ston K
in
print "Kelvin: "; println K;
print "Celcius: "; println ` KtoC K;
print "Fahrenheit: "; println ` KtoF K;
print "Rankine: "; println ` KtoR K
end

## NetRexx

/* NetRexx */
options replace format comments java crossref symbols

numeric digits 20

runSample(arg)
return

-- ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/*
+ Kelvin Celsius Fahrenheit Rankine Delisle Newton Réaumur Rømer
K T T-273.15 T*9/5-459.67 T*9/5 (373.15-T)*3/2 (T-273.15)*33/100 (T-273.15)*4/5 (T-273.15)*21/40+7.5
C T+273.15 T T*9/5+32 (T+273.15)*9/5 (100-T)*3/2 T*33/100 T*4/5 T*21/40+7.5
F (T+459.67)*5/9 (T-32)*5/9 T T+459.67 (212-T)*5/6 (T-32)*11/60 (T-32)*4/9 (T-32)*7/24+7.5
R T*5/9 (T-491.67)*5/9 T-459.67 T (671.67-T)*5/6 (T-491.67)*11/60 (T-491.67)*4/9 (T-491.67)*7/24+7.5
De 373.15-T*2/3 100-T*2/3 212-T*6/5 671.67-T*6/5 T 33-T*11/50 80-T*8/15 60-T*7/20
N T*100/33+273.15 T*100/33 T*60/11+32 T*60/11+491.67 (33-T)*50/11 T T*80/33 T*35/22+7.5
Ré T*5/4+273.15 T*5/4 T*9/4+32 T*9/4+491.67 (80-T)*15/8 T*33/80 T T*21/32+7.5
*/

method temperatureConversion(scaleFrom, scaleTo, T) public static

parse 'KELVIN CELSIUS FAHRENHEIT RANKINE DELISLE NEWTON REAUMUR ROEMER' -
KELVIN CELSIUS FAHRENHEIT RANKINE DELISLE NEWTON REAUMUR ROEMER .
scaleFrom = scaleFrom.upper()
scaleTo = scaleTo.upper()
select label sF case scaleFrom
when KELVIN then do
select case scaleTo
when KELVIN then val = T
when CELSIUS then val = T - 273.15
when FAHRENHEIT then val = T * 9 / 5 - 459.67
when RANKINE then val = T * 9 / 5
when DELISLE then val = (373.15 - T) * 3 / 2
when NEWTON then val = (T - 273.15) * 33 / 100
when REAUMUR then val = (T - 273.15) * 4 / 5
when ROEMER then val = (T - 273.15) * 21 / 40 + 7.5
otherwise signal IllegalArgumentException(scaleFrom',' scaleTo',' T)
end
end
when CELSIUS then do
select case scaleTo
when KELVIN then val = T + 273.15
when CELSIUS then val = T
when FAHRENHEIT then val = T * 9 / 5 + 32
when RANKINE then val = (T + 273.15) * 9 / 5
when DELISLE then val = (100 - T) * 3 / 2
when NEWTON then val = T * 33 / 100
when REAUMUR then val = T * 4 / 5
when ROEMER then val = T * 21 / 40 + 7.5
otherwise signal IllegalArgumentException(scaleFrom',' scaleTo',' T)
end
end
when FAHRENHEIT then do
select case scaleTo
when KELVIN then val = (T + 459.67) * 5 / 9
when CELSIUS then val = (T - 32) * 5 / 9
when FAHRENHEIT then val = T
when RANKINE then val = T + 459.67
when DELISLE then val = (212 - T) * 5 / 6
when NEWTON then val = (T - 32) * 11 / 60
when REAUMUR then val = (T - 32) * 4 / 9
when ROEMER then val = (T - 32) * 7 / 24 + 7.5
otherwise signal IllegalArgumentException(scaleFrom',' scaleTo',' T)
end
end
when RANKINE then do
select case scaleTo
when KELVIN then val = T * 5 / 9
when CELSIUS then val = (T - 491.67) * 5 / 9
when FAHRENHEIT then val = T - 459.67
when RANKINE then val = T
when DELISLE then val = (671.67 - T) * 5 / 6
when NEWTON then val = (T - 491.67) * 11 / 60
when REAUMUR then val = (T - 491.67) * 4 / 9
when ROEMER then val = (T - 491.67) * 7 / 24 + 7.5
otherwise signal IllegalArgumentException(scaleFrom',' scaleTo',' T)
end
end
when DELISLE then do
select case scaleTo
when KELVIN then val = 373.15 - T * 2 / 3
when CELSIUS then val = 100 - T * 2 / 3
when FAHRENHEIT then val = 212 - T * 6 / 5
when RANKINE then val = 671.67 - T * 6 / 5
when DELISLE then val = T
when NEWTON then val = 33 - T * 11 / 50
when REAUMUR then val = 80 - T * 8 / 15
when ROEMER then val = 60 - T * 7 / 20
otherwise signal IllegalArgumentException(scaleFrom',' scaleTo',' T)
end
end
when NEWTON then do
select case scaleTo
when KELVIN then val = T * 100 / 33 + 273.15
when CELSIUS then val = T * 100 / 33
when FAHRENHEIT then val = T * 60 / 11 + 32
when RANKINE then val = T * 60 / 11 + 491.67
when DELISLE then val = (33 - T) * 50 / 11
when NEWTON then val = T
when REAUMUR then val = T * 80 / 33
when ROEMER then val = T * 35 / 22 + 7.5
otherwise signal IllegalArgumentException(scaleFrom',' scaleTo',' T)
end
end
when REAUMUR then do
select case scaleTo
when KELVIN then val = T * 5 / 4 + 273.15
when CELSIUS then val = T * 5 / 4
when FAHRENHEIT then val = T * 9 / 4 + 32
when RANKINE then val = T * 9 / 4 + 491.67
when DELISLE then val = (80 - T) * 15 / 8
when NEWTON then val = T * 33 / 80
when REAUMUR then val = T
when ROEMER then val = T * 21 / 32 + 7.5
otherwise signal IllegalArgumentException(scaleFrom',' scaleTo',' T)
end
end
when ROEMER then do
select case scaleTo
when KELVIN then val = (T - 7.5) * 40 / 21 + 273.15
when CELSIUS then val = (T - 7.5) * 40 / 21
when FAHRENHEIT then val = (T - 7.5) * 24 / 7 + 32
when RANKINE then val = (T - 7.5) * 24 / 7 + 491.67
when DELISLE then val = (60 - T) * 20 / 7
when NEWTON then val = (T - 7.5) * 22 / 35
when REAUMUR then val = (T - 7.5) * 32 / 21
when ROEMER then val = T
otherwise signal IllegalArgumentException(scaleFrom',' scaleTo',' T)
end
end
otherwise
signal IllegalArgumentException(scaleFrom',' scaleTo',' T)
end sF

return val

-- ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
method runSample(arg) public static

tlist = [ -
/* C....... F....... K....... R.......*/ -
' 5500.00 9932.00 5773.15 10391.67', -
' 300.00 572.00 573.15 1031.67', -
' 200.00 392.00 473.15 851.67', -
' 100.00 212.00 373.15 671.67', -
' 37.00 98.60 310.15 558.27', -
' 0.00 32.00 273.15 491.67', -
' -100.00 -148.00 173.15 311.67', -
' -200.00 -328.00 73.15 131.67', -
' -252.15 -421.87 21.00 37.80', -
' -273.15 -459.67 0.00 0.00' -
]

parse 'CELSIUS FAHRENHEIT KELVIN RANKINE' CELSIUS FAHRENHEIT KELVIN RANKINE .
loop temp over tlist
parse temp ttC ttF ttK ttR .
say ' C....... F....... K....... R.......'
say 'C ' -
temperatureConversion(CELSIUS, CELSIUS, ttC).format(5, 2) -
temperatureConversion(CELSIUS, FAHRENHEIT, ttC).format(5, 2) -
temperatureConversion(CELSIUS, KELVIN, ttC).format(5, 2) -
temperatureConversion(CELSIUS, RANKINE, ttC).format(5, 2)

say 'F ' -
temperatureConversion(FAHRENHEIT, CELSIUS, ttF).format(5, 2) -
temperatureConversion(FAHRENHEIT, FAHRENHEIT, ttF).format(5, 2) -
temperatureConversion(FAHRENHEIT, KELVIN, ttF).format(5, 2) -
temperatureConversion(FAHRENHEIT, RANKINE, ttF).format(5, 2)

say 'K ' -
temperatureConversion(KELVIN, CELSIUS, ttK).format(5, 2) -
temperatureConversion(KELVIN, FAHRENHEIT, ttK).format(5, 2) -
temperatureConversion(KELVIN, KELVIN, ttK).format(5, 2) -
temperatureConversion(KELVIN, RANKINE, ttK).format(5, 2)

say 'R ' -
temperatureConversion(RANKINE, CELSIUS, ttR).format(5, 2) -
temperatureConversion(RANKINE, FAHRENHEIT, ttR).format(5, 2) -
temperatureConversion(RANKINE, KELVIN, ttR).format(5, 2) -
temperatureConversion(RANKINE, RANKINE, ttR).format(5, 2)
say
end temp

return

Output:
C....... F....... K....... R.......
C   5500.00  9932.00  5773.15 10391.67
F   5500.00  9932.00  5773.15 10391.67
K   5500.00  9932.00  5773.15 10391.67
R   5500.00  9932.00  5773.15 10391.67

C....... F....... K....... R.......
C    300.00   572.00   573.15  1031.67
F    300.00   572.00   573.15  1031.67
K    300.00   572.00   573.15  1031.67
R    300.00   572.00   573.15  1031.67

C....... F....... K....... R.......
C    200.00   392.00   473.15   851.67
F    200.00   392.00   473.15   851.67
K    200.00   392.00   473.15   851.67
R    200.00   392.00   473.15   851.67

C....... F....... K....... R.......
C    100.00   212.00   373.15   671.67
F    100.00   212.00   373.15   671.67
K    100.00   212.00   373.15   671.67
R    100.00   212.00   373.15   671.67

C....... F....... K....... R.......
C     37.00    98.60   310.15   558.27
F     37.00    98.60   310.15   558.27
K     37.00    98.60   310.15   558.27
R     37.00    98.60   310.15   558.27

C....... F....... K....... R.......
C      0.00    32.00   273.15   491.67
F      0.00    32.00   273.15   491.67
K      0.00    32.00   273.15   491.67
R      0.00    32.00   273.15   491.67

C....... F....... K....... R.......
C   -100.00  -148.00   173.15   311.67
F   -100.00  -148.00   173.15   311.67
K   -100.00  -148.00   173.15   311.67
R   -100.00  -148.00   173.15   311.67

C....... F....... K....... R.......
C   -200.00  -328.00    73.15   131.67
F   -200.00  -328.00    73.15   131.67
K   -200.00  -328.00    73.15   131.67
R   -200.00  -328.00    73.15   131.67

C....... F....... K....... R.......
C   -252.15  -421.87    21.00    37.80
F   -252.15  -421.87    21.00    37.80
K   -252.15  -421.87    21.00    37.80
R   -252.15  -421.87    21.00    37.80

C....... F....... K....... R.......
C   -273.15  -459.67     0.00     0.00
F   -273.15  -459.67     0.00     0.00
K   -273.15  -459.67     0.00     0.00
R   -273.15  -459.67     0.00     0.00

## NewLISP

(define (to-celsius k)
(- k 273.15)
)

(define (to-fahrenheit k)
(- (* k 1.8) 459.67)
)

(define (to-rankine k)
(* k 1.8)
)

(define (kelvinConversion k)
(if (number? k)
(println k " kelvin is equivalent to:\n"
(to-celsius k) " celsius\n"
(to-fahrenheit k) " fahrenheit\n"
(to-rankine k) " rankine")
(println "Please enter a number only, with no º or letter. ")
)
)

Output:
21 kelvin is equivalent to:
-252 celsius
-438 fahrenheit
21 rankine

## Nim

import rdstdin, strutils, strfmt

while true:
let k = parseFloat readLineFromStdin "K ? "
echo "{:g} Kelvin = {:g} Celsius = {:g} Fahrenheit = {:g} Rankine degrees".fmt(
k, k - 273.15, k * 1.8 - 459.67, k * 1.8)

Sample usage:

K ? 21.0
21 Kelvin = -252.15 Celsius = -421.87 Fahrenheit = 37.8 Rankine degrees
K ? 222.2
222.2 Kelvin = -50.95 Celsius = -59.71 Fahrenheit = 399.96 Rankine degrees

## Objeck

class Temperature {
function : Main(args : String[]) ~ Nil {
c := KelvinToCelsius(k);
f := KelvinToFahrenheit(k);
r := KelvinToRankine(k);

"K: {\$k}"->PrintLine();
"C: {\$c}"->PrintLine();
"F: {\$f}"->PrintLine();
"R: {\$r}"->PrintLine();
}

function : KelvinToCelsius(k : Float) ~ Float {
return k - 273.15;
}

function : KelvinToFahrenheit(k : Float) ~ Float {
return k * 1.8 - 459.67;
}

function : KelvinToRankine(k : Float) ~ Float {
return k * 1.8;
}
}

K: 21.0
C: -252.150
F: -421.870
R: 37.800

## Objective-C

#import <Foundation/Foundation.h>

int main(int argc, const char * argv[])
{
@autoreleasepool {
if(argc > 1)
{
NSString *arg1 = [NSString stringWithCString:argv[1] encoding:NSUTF8StringEncoding];
// encoding shouldn't matter in this case
double kelvin = [arg1 doubleValue];

NSLog(@"K %.2f",kelvin);
NSLog(@"C %.2f\n", kelvin - 273.15);
NSLog(@"F %.2f\n", (kelvin * 1.8) - 459.67);
NSLog(@"R %.2f", kelvin * 1.8);
}
}
return 0;
}

## OCaml

let print_temp s t =
print_string s;
print_endline (string_of_float t);;

let kelvin_to_celsius k =
k -. 273.15;;

let kelvin_to_fahrenheit k =
(kelvin_to_celsius k)*. 9./.5. +. 32.00;;

let kelvin_to_rankine k =
(kelvin_to_celsius k)*. 9./.5. +. 491.67;;

print_endline "Enter a temperature in Kelvin please:";
let k = read_float () in
print_temp "K " k;
print_temp "C " (kelvin_to_celsius k);
print_temp "F " (kelvin_to_fahrenheit k);
print_temp "R " (kelvin_to_rankine k);;

Sample session:

Enter a temperature in Kelvin please:
184
K 184.
C -89.15
F -128.47
R 331.2

## Oforth

: kelvinToCelsius  273.15 - ;
: kelvinToFahrenheit 1.8 * 459.67 - ;
: kelvinToRankine 1.8 * ;

: testTemp(n)
n kelvinToCelsius println
n kelvinToFahrenheit println
n kelvinToRankine println ;
Output:
>21 testTemp
-252.15
-421.87
37.8

## PARI/GP

f(x)=[x,x-273.15,1.8*x-459.67,1.8*x]

## Pascal

program TemperatureConvert;

type
TemperatureType = (C, F, K, R);

var
kelvin: real;

function ConvertTemperature(temperature: real; fromType, toType: TemperatureType): real;

var
initial, result: real;

begin
(* We are going to first convert whatever we're given into Celsius.
Then we'll convert that into whatever we're asked to convert into.
Maybe not the most efficient way to do this, but easy to understand
and should make it easier to add any additional temperature units. *)

if fromType <> toType then
begin
case fromType of (* first convert the temperature into Celsius *)
C:
initial := temperature;
F:
initial := (temperature - 32) / 1.8;
K:
initial := temperature - 273.15;
R:
initial := (temperature - 491.67) / 1.8;
end;
case toType of (* now convert from Celsius into whatever degree type was asked for *)
C:
result := initial;
F:
result := (initial * 1.8) + 32;
K:
result := initial + 273.15;
R:
result := (initial * 1.8) + 491.67;
end;
end
else (* no point doing all that math if we're asked to convert from and to the same type *)
result := temperature;
ConvertTemperature := result;
end;

begin
write('Temperature to convert (in kelvins): ');
writeln(kelvin : 3 : 2, ' in kelvins is ');
writeln(' ', ConvertTemperature(kelvin, K, C) : 3 : 2, ' in degrees Celsius.');
writeln(' ', ConvertTemperature(kelvin, K, F) : 3 : 2, ' in degrees Fahrenheit.');
writeln(' ', ConvertTemperature(kelvin, K, R) : 3 : 2, ' in degrees Rankine.');
end.
Output:
Temperature to convert (in kelvins): 373.15
373.15 in kelvins is
100.00 in degrees Celsius.
212.00 in degrees Fahrenheit.
671.67 in degrees Rankine.

## Perl

my %scale = (
Celcius => { factor => 1 , offset => -273.15 },
Rankine => { factor => 1.8, offset => 0 },
Fahrenheit => { factor => 1.8, offset => -459.67 },
);

print "Enter a temperature in Kelvin: ";
chomp(my \$kelvin = <STDIN>);
die "No such temperature!\n" unless \$kelvin > 0;

foreach (sort keys %scale) {
printf "%12s:%8.2f\n", \$_, \$kelvin * \$scale{\$_}{factor} + \$scale{\$_}{offset};
}
Output:
Enter a temperature in Kelvin: 21
Celcius: -252.15
Fahrenheit: -421.87
Rankine:   37.80

## Perl 6

Translation of: Perl
my %scale =
Celcius => { factor => 1 , offset => -273.15 },
Rankine => { factor => 1.8, offset => 0 },
Fahrenheit => { factor => 1.8, offset => -459.67 },
;

my \$kelvin = +prompt "Enter a temperature in Kelvin: ";
die "No such temperature!" if \$kelvin < 0;

for %scale.sort {
printf "%12s: %7.2f\n", .key, \$kelvin * .value<factor> + .value<offset>;
}
Output:
Enter a temperature in Kelvin: 21
Celcius: -252.15
Fahrenheit: -421.87
Rankine:   37.80

Alternative version that accepts the input in any of the four scales:

while my \$answer = prompt 'Temperature: ' {
my \$k = do given \$answer {
when s/:i C \$// { \$_ + 273.15 }
when s/:i F \$// { (\$_ + 459.67) / 1.8 }
when s/:i R \$// { \$_ / 1.8 }
when s/:i K \$// { \$_ }
default { \$_ }
}
say " { \$k }K";
say " { \$k - 273.15 }℃";
say " { \$k * 1.8 - 459.67 }℉";
say " { \$k * 1.8 }R";
}
Output:
Temperature: 0
0K
-273.15℃
-459.67℉
0R
Temperature: 0c
273.15K
0℃
32℉
491.67R
Temperature: 212f
373.15K
100℃
212℉
671.67R
Temperature: -40c
233.15K
-40℃
-40℉
419.67R

## Phix

Modified copy of Euphoria

atom K = prompt_number("Enter temperature in Kelvin >=0: ",{0,1e307})
printf(1," Kelvin: %5.2f\n Celsius: %5.2f\nFahrenheit: %5.2f\n Rankine: %5.2f\n\n",
{K, K-273.15, K*1.8-459.67, K*1.8})

Output:
Enter temperature in Kelvin >=0: 300
Kelvin: 300.00
Celsius: 26.85
Fahrenheit: 80.33
Rankine: 540.00

## PHP

while (true) {
echo "\nEnter a value in kelvin (q to quit): ";
if (\$kelvin = trim(fgets(STDIN))) {
if (\$kelvin == 'q') {
echo 'quitting';
break;
}
if (is_numeric(\$kelvin)) {
\$kelvin = floatVal(\$kelvin);
if (\$kelvin >= 0) {
printf(" K %2.2f\n", \$kelvin);
printf(" C %2.2f\n", \$kelvin - 273.15);
printf(" F %2.2f\n", \$kelvin * 1.8 - 459.67);
printf(" R %2.2f\n", \$kelvin * 1.8);
} else printf(" %2.2f K is below absolute zero\n", \$kelvin);
}
}
}
Output:
Enter a value in kelvin (q to quit): 21
K  21.00
C  -252.15
F  -421.87
R  37.80

Enter a value in kelvin (q to quit): q
quitting

## PicoLisp

(scl 2)

(de convertKelvin (Kelvin)
(for X
(quote
(K . prog)
(C (K) (- K 273.15))
(F (K) (- (*/ K 1.8 1.0) 459.67))
(R (K) (*/ K 1.8 1.0)) )
(tab (-3 8)
(car X)
(format ((cdr X) Kelvin) *Scl) ) ) )

Test:

(convertKelvin 21.0)
Output:
K     21.00
C   -252.15
F   -421.87
R     37.80

## PL/I

*process source attributes xref;
/* PL/I **************************************************************
* 15.08.2013 Walter Pachl translated from NetRexx
* temperatures below 0K are considered invalid
*********************************************************************/

temperature: Proc Options(main);
Dcl sysin record Input;
On Endfile(sysin) Goto eoj;
On Record(sysin);
Dcl 1 dat,
2 t Pic'SSSS9V.99',
2 * char( 1),
2 from char(10),
2 * char( 1),
2 to char(10);
Do Forever;
If tc(t,from,'KELVIN')<0 Then
Put Edit('Input (',t,from,') invalid. Below absolute zero')
(Skip,a,f(8,2),x(1),a,a);
Else
Put edit(t,from,' -> ',tc(t,from,to),to)
(skip,f(8,2),x(1),a(10),a,f(8,2),x(1),a(10));
End;
eoj: Return;

tc: Procedure(T,scaleFrom,scaleTo) Returns(Dec Fixed(8,2));
Dcl t Pic'SSSS9V.99';
Dcl (val) Dec Fixed(8,2);
Dcl (scaleFrom,scaleTo) Char(10);
select(scaleFrom);
when('KELVIN ') do;
select(scaleTo);
when('KELVIN ') val = T;
when('CELSIUS ') val = T - 273.15;
when('FAHRENHEIT') val = T * 9 / 5 - 459.67;
when('RANKINE ') val = T * 9 / 5;
when('DELISLE ') val = (373.15 - T) * 3 / 2;
when('NEWTON ') val = (T - 273.15) * 33 / 100;
when('REAUMUR ') val = (T - 273.15) * 4 / 5;
when('ROEMER ') val = (T - 273.15) * 21 / 40 + 7.5;
otherwise Do;
Put Edit('scaleTo=',scaleTo)(Skip,a,a);
Call err(1);
End;
end;
end;
when('CELSIUS') do;
select(scaleTo);
when('KELVIN ') val = T + 273.15;
when('CELSIUS ') val = T;
when('FAHRENHEIT') val = T * 9 / 5 + 32;
when('RANKINE ') val = (T + 273.15) * 9 / 5;
when('DELISLE ') val = (100 - T) * 3 / 2;
when('NEWTON ') val = T * 33 / 100;
when('REAUMUR ') val = T * 4 / 5;
when('ROEMER ') val = T * 21 / 40 + 7.5;
otherwise Call err(2);
end;
end;
when('FAHRENHEIT') do;
select(scaleTo);
when('KELVIN ') val = (T + 459.67) * 5 / 9;
when('CELSIUS ') val = (T - 32) * 5 / 9;
when('FAHRENHEIT') val = T;
when('RANKINE ') val = T + 459.67;
when('DELISLE ') val = (212 - T) * 5 / 6;
when('NEWTON ') val = (T - 32) * 11 / 60;
when('REAUMUR ') val = (T - 32) * 4 / 9;
when('ROEMER ') val = (T - 32) * 7 / 24 + 7.5;
otherwise Call err(3);
end;
end;
when('RANKINE') do;
select(scaleTo);
when('KELVIN ') val = T * 5 / 9;
when('CELSIUS ') val = (T - 491.67) * 5 / 9;
when('FAHRENHEIT') val = T - 459.67;
when('RANKINE ') val = T;
when('DELISLE ') val = (671.67 - T) * 5 / 6;
when('NEWTON ') val = (T - 491.67) * 11 / 60;
when('REAUMUR ') val = (T - 491.67) * 4 / 9;
when('ROEMER ') val = (T - 491.67) * 7 / 24 + 7.5;
otherwise Call err(4);
end;
end;
when('DELISLE') do;
select(scaleTo);
when('KELVIN ') val = 373.15 - T * 2 / 3;
when('CELSIUS ') val = 100 - T * 2 / 3;
when('FAHRENHEIT') val = 212 - T * 6 / 5;
when('RANKINE ') val = 671.67 - T * 6 / 5;
when('DELISLE ') val = T;
when('NEWTON ') val = 33 - T * 11 / 50;
when('REAUMUR ') val = 80 - T * 8 / 15;
when('ROEMER ') val = 60 - T * 7 / 20;
otherwise Call err(5);
end;
end;
when('NEWTON') do;
select(scaleTo);
when('KELVIN ') val = T * 100 / 33 + 273.15;
when('CELSIUS ') val = T * 100 / 33;
when('FAHRENHEIT') val = T * 60 / 11 + 32;
when('RANKINE ') val = T * 60 / 11 + 491.67;
when('DELISLE ') val = (33 - T) * 50 / 11;
when('NEWTON ') val = T;
when('REAUMUR ') val = T * 80 / 33;
when('ROEMER ') val = T * 35 / 22 + 7.5;
otherwise Call err(6);
end;
end;
when('REAUMUR') do;
select(scaleTo);
when('KELVIN ') val = T * 5 / 4 + 273.15;
when('CELSIUS ') val = T * 5 / 4;
when('FAHRENHEIT') val = T * 9 / 4 + 32;
when('RANKINE ') val = T * 9 / 4 + 491.67;
when('DELISLE ') val = (80 - T) * 15 / 8;
when('NEWTON ') val = T * 33 / 80;
when('REAUMUR ') val = T;
when('ROEMER ') val = T * 21 / 32 + 7.5;
otherwise Call err(7);
end;
end;
when('ROEMER') do;
select(scaleTo);
when('KELVIN ') val = (T - 7.5) * 40 / 21 + 273.15;
when('CELSIUS ') val = (T - 7.5) * 40 / 21;
when('FAHRENHEIT') val = (T - 7.5) * 24 / 7 + 32;
when('RANKINE ') val = (T - 7.5) * 24 / 7 + 491.67;
when('DELISLE ') val = (60 - T) * 20 / 7;
when('NEWTON ') val = (T - 7.5) * 22 / 35;
when('REAUMUR ') val = (T - 7.5) * 32 / 21;
when('ROEMER ') val = T;
otherwise Call err(8);
end;
end;
otherwise Call err(9);
end;
return(val);
err: Proc(e);
Dcl e Dec fixed(1);
Put Edit('error ',e,' invalid input')(Skip,a,f(1),a);
val=0;
End;
End;
End;
Output:
21.00 KELVIN     ->  -252.15 CELSIUS
21.00 KELVIN     ->  -421.87 FAHRENHEIT
21.00 KELVIN     ->    37.80 RANKINE
Input (  600.00 DELISLE   ) invalid. Below absolute zero
Input (   -1.00 KELVIN    ) invalid. Below absolute zero
Input ( -300.00 CELSIUS   ) invalid. Below absolute zero
212.00 FAHRENHEIT ->   100.00 CELSIUS
0.00 FAHRENHEIT ->   -17.77 CELSIUS
0.00 CELSIUS    ->    32.00 FAHRENHEIT
37.00 CELSIUS    ->    98.60 FAHRENHEIT

## PowerShell

Translation of: Tcl
function temp(\$k){
try{
\$c = \$k - 273.15
\$r = \$k / 5 * 9
\$f = \$r - 459.67
} catch {
Write-host "Input error."
return
}

Write-host ""
Write-host " TEMP (Kelvin)  : " \$k
Write-host " TEMP (Celsius)  : " \$c
Write-host " TEMP (Fahrenheit): " \$f
Write-host " TEMP (Rankine)  : " \$r
Write-host ""

}

\$input=Read-host "Enter a temperature in Kelvin"
temp \$input
Output:
PS> ./TEMPS
Enter a temperature in Kelvin: 100

TEMP (Kelvin)    :  100
TEMP (Celsius)   :  -173.15
TEMP (Fahrenheit):  -279.67
TEMP (Rankine)   :  180

PS>

### PowerShell Alternate Version

A more "PowerShelly" way to do it.

function Convert-Kelvin
{
[CmdletBinding()]
[OutputType([PSCustomObject])]
Param
(
[Parameter(Mandatory=\$true,
ValueFromPipeline=\$true,
ValueFromPipelineByPropertyName=\$true,
Position=0)]
[double]
\$InputObject
)

Process
{
foreach (\$kelvin in \$InputObject)
{
[PSCustomObject]@{
Kelvin = \$kelvin
Celsius = \$kelvin - 273.15
Fahrenheit = \$kelvin * 1.8 - 459.67
Rankine = \$kelvin * 1.8
}
}
}
}

21, 100 | Convert-Kelvin

Output:
Kelvin Celsius Fahrenheit Rankine
------ ------- ---------- -------
21 -252.15    -421.87    37.8
100 -173.15    -279.67     180

## Pure Data

temperature.pd

#N canvas 200 200 640 600 10;
#X floatatom 130 54 8 0 0 2 Kelvin chgk -;
#X obj 130 453 rnd2;
#X floatatom 130 493 8 0 0 1 K - -;
#X floatatom 251 54 8 0 0 2 Celsius chgc -;
#X obj 251 453 rnd2;
#X floatatom 251 493 8 0 0 1 °C - -;
#X floatatom 374 54 8 0 0 2 Fahrenheit chgf -;
#X obj 374 453 rnd2;
#X floatatom 374 493 8 0 0 1 °F - -;
#X floatatom 498 54 8 0 0 2 Rankine chgr -;
#X obj 498 453 rnd2;
#X floatatom 498 493 8 0 0 1 °Ra - -;
#X obj 65 133 - 273.15;
#X obj 65 244 * 1.8;
#X obj 65 267 + 32;
#X obj 65 363 + 459.67;
#X obj 186 133 * 1.8;
#X obj 186 156 + 32;
#X obj 186 268 + 459.67;
#X obj 186 310 / 1.8;
#X obj 309 133 + 459.67;
#X obj 309 215 / 1.8;
#X obj 309 291 - 273.15;
#X obj 433 133 / 1.8;
#X obj 433 223 - 273.15;
#X obj 433 294 * 1.8;
#X obj 433 317 + 32;
#X text 20 53 Input:;
#X text 20 492 Output:;
#X connect 0 0 1 0;
#X connect 0 0 12 0;
#X connect 1 0 2 0;
#X connect 3 0 4 0;
#X connect 3 0 16 0;
#X connect 4 0 5 0;
#X connect 6 0 7 0;
#X connect 6 0 20 0;
#X connect 7 0 8 0;
#X connect 9 0 10 0;
#X connect 9 0 23 0;
#X connect 10 0 11 0;
#X connect 12 0 13 0;
#X connect 12 0 4 0;
#X connect 13 0 14 0;
#X connect 14 0 15 0;
#X connect 14 0 7 0;
#X connect 15 0 10 0;
#X connect 16 0 17 0;
#X connect 17 0 18 0;
#X connect 17 0 7 0;
#X connect 18 0 19 0;
#X connect 18 0 10 0;
#X connect 19 0 1 0;
#X connect 20 0 21 0;
#X connect 20 0 10 0;
#X connect 21 0 22 0;
#X connect 21 0 1 0;
#X connect 22 0 4 0;
#X connect 23 0 24 0;
#X connect 23 0 1 0;
#X connect 24 0 25 0;
#X connect 24 0 4 0;
#X connect 25 0 26 0;
#X connect 26 0 7 0;

Plugin to round the results to at most 2 digits:

rnd.pd

#N canvas 880 200 450 300 10;
#X obj 77 34 inlet;
#X obj 77 113 * 100;
#X obj 77 135 + 0.5;
#X obj 132 135 < 0;
#X obj 77 172 -;
#X obj 77 194 int;
#X obj 77 216 / 100;
#X obj 77 238 outlet;
#X connect 0 0 1 0;
#X connect 0 0 3 0;
#X connect 1 0 2 0;
#X connect 2 0 4 0;
#X connect 3 0 4 1;
#X connect 4 0 5 0;
#X connect 5 0 6 0;
#X connect 6 0 7 0;

## PureBasic

Procedure.d Kelvin2Celsius(tK.d)    : ProcedureReturn tK-273.15     : EndProcedure
Procedure.d Kelvin2Fahrenheit(tK.d) : ProcedureReturn tK*1.8-459.67 : EndProcedure
Procedure.d Kelvin2Rankine(tK.d)  : ProcedureReturn tK*1.8  : EndProcedure

OpenConsole()
Repeat
Print("Temperatur Kelvin? ") : Kelvin.d = ValD(Input())
PrintN("Conversion:")
PrintN(#TAB\$+"Celsius "+#TAB\$+RSet(StrD(Kelvin2Celsius(Kelvin),2),8,Chr(32)))
PrintN(#TAB\$+"Fahrenheit"+#TAB\$+RSet(StrD(Kelvin2Fahrenheit(Kelvin),2),8,Chr(32)))
PrintN(#TAB\$+"Rankine "+#TAB\$+RSet(StrD(Kelvin2Rankine(Kelvin),2),8,Chr(32)))
PrintN("ESC = End.")
Repeat
k\$=Inkey() : Delay(50) : If RawKey()=#ESC : End : EndIf
Until RawKey()
ForEver
Temperatur Kelvin? 21
Conversion:
Celsius          -252.15
Fahrenheit       -421.87
Rankine            37.80
ESC = End.

## Python

>>> while True:
k = float(input('K ? '))
print("%g Kelvin = %g Celsius = %g Fahrenheit = %g Rankine degrees."
% (k, k - 273.15, k * 1.8 - 459.67, k * 1.8))

K ? 21.0
21 Kelvin = -252.15 Celsius = -421.87 Fahrenheit = 37.8 Rankine degrees.
K ? 222.2
222.2 Kelvin = -50.95 Celsius = -59.71 Fahrenheit = 399.96 Rankine degrees.
K ?

### Python: Universal conversion

This converts from any one of the units to all the others

>>> toK = {'C': (lambda c: c + 273.15),
'F': (lambda f: (f + 459.67) / 1.8),
'R': (lambda r: r / 1.8),
'K': (lambda k: k) }
>>> while True:
magnitude, unit = input('<value> <K/R/F/C> ? ').split()
k = toK[unit](float(magnitude))
print("%g Kelvin = %g Celsius = %g Fahrenheit = %g Rankine degrees."
% (k, k - 273.15, k * 1.8 - 459.67, k * 1.8))

<value> <K/R/F/C> ? 222.2 K
222.2 Kelvin = -50.95 Celsius = -59.71 Fahrenheit = 399.96 Rankine degrees.
<value> <K/R/F/C> ? -50.95 C
222.2 Kelvin = -50.95 Celsius = -59.71 Fahrenheit = 399.96 Rankine degrees.
<value> <K/R/F/C> ? -59.71 F
222.2 Kelvin = -50.95 Celsius = -59.71 Fahrenheit = 399.96 Rankine degrees.
<value> <K/R/F/C> ? 399.96 R
222.2 Kelvin = -50.95 Celsius = -59.71 Fahrenheit = 399.96 Rankine degrees.
<value> <K/R/F/C> ?

## Racket

Although not exactly the shortest code, the converter function can turn any temperature into any other

#lang racket
(define (converter temp init final)
(define to-k
(case init
('k temp)
('c (+ 273.15 temp))
('f (* (+ temp 459.67) 5/9))
('r (* temp 5/9))))
(case final
('k to-k)
('c (- to-k 273.15))
('f (- (* to-k 9/5) 459.67))
('r (* to-k 1.8))))

(define (kelvin-to-all temp)
(display (format "Kelvin: ~a \nCelsius: ~a \nFahrenheit: ~a \nRankine: ~a \n"
temp
(converter temp 'k 'c)
(converter temp 'k 'f)
(converter temp 'k 'r))))
(kelvin-to-all 21)
;Kelvin: 21
;Celsius: -252.14999999999998
;Fahrenheit: -421.87
;Rankine: 37.800000000000004

## REXX

### abridged

This REXX version supports:

• (alternate spellings with optional   degree   or   degrees   preceding the scale name):
• alternate temperature scale names
• supports   any to all   conversions
• supports   any to any   conversion   (with the   TO   option)
• support of some common misspellings   (it knows what you mean)
• support of some common temperature scales:
• Delisle
• Fahrenheit
• kelvin
• Newton
• Rankine
• Reaumur,   Réaumur
• Romer,   Rømer,   Roemer
• multiple temperatures in a list
• specification of which temperature scale to be used for conversion
• conversion of a temperature to:
• all other temperature scales
• a specific temperature scale
• supports proper pluralization of kelvin
• comments (annotation notes) allowed within the list
• aligned output (whole numbers and decimal fractions)
/*REXX program  converts  temperatures  for a number (8)  of  temperature scales.       */
numeric digits 120 /*be able to support some huge numbers.*/
parse arg tList /*get the specified temperature list. */

do until tList='' /*process the list of temperatures. */
parse var tList x ',' tList /*temps are separated by commas. */
x=translate(x,'((',"[{") /*support other grouping symbols. */
x=space(x); parse var x z '(' /*handle any comments (if any). */
parse upper var z z ' TO '  ! . /*separate the TO option from number.*/
if !=='' then !='ALL'; all=!=='ALL' /*allow specification of "TO" opt*/
if z=='' then call serr "no arguments were specified." /*oops-ay. */
_=verify(z, '+-.0123456789') /*list of valid numeral/number thingys.*/
n=z
if _\==0 then do
if _==1 then call serr 'illegal temperature:' z
n=left(z, _-1) /*pick off the number (hopefully). */
u=strip(substr(z, _)) /*pick off the temperature unit. */
end
else u='k' /*assume kelvin as per task requirement*/

if \datatype(n, 'N') then call serr 'illegal number:' n
if \all then do /*is there is a TO ααα scale? */
call name ! /*process the TO abbreviation. */
!=sn /*assign the full name to  ! */
end /*!: now contains temperature full name*/
call name u /*allow alternate scale (miss)spellings*/

select /*convert ──► °Fahrenheit temperatures.*/
when sn=='CELSIUS' then F=n * 9/5 + 32
when sn=='DELISLE' then F=212 -(n * 6/5)
when sn=='FAHRENHEIT' then F=n
when sn=='KELVIN' then F=n * 9/5 - 459.67
when sn=='NEWTON' then F=n * 60/11 + 32
when sn=='RANKINE' then F=n - 459.67 /*a single R is taken as Rankine.*/
when sn=='REAUMUR' then F=n * 9/4 + 32
when sn=='ROMER' then F=(n-7.5) * 27/4 + 32
otherwise call serr 'illegal temperature scale: ' u
end /*select*/

K = (F + 459.67) * 5/9 /*compute temperature to kelvins. */
say right(' ' x, 79, "─") /*show the original value, scale, sep. */
if all | !=='CELSIUS' then say \$( ( F - 32 ) * 5/9 ) 'Celsius'
if all | !=='DELISLE' then say \$( ( 212 - F ) * 5/6 ) 'Delisle'
if all | !=='FAHRENHEIT' then say \$( F ) 'Fahrenheit'
if all | !=='KELVIN' then say \$( K ) 'kelvin's(K)
if all | !=='NEWTON' then say \$( ( F - 32 ) * 11/60 ) 'Newton'
if all | !=='RANKINE' then say \$( F + 459.67 ) 'Rankine'
if all | !=='REAUMUR' then say \$( ( F - 32 ) * 4/9 ) 'Reaumur'
if all | !=='ROMER' then say \$( ( F - 32 ) * 4/27 + 7.5 ) 'Romer'
end /*until*/

exit /*stick a fork in it, we're all done. */
/*──────────────────────────────────────────────────────────────────────────────────────*/
s: if arg(1)==1 then return arg(3); return word(arg(2) 's',1)
serr: say; say '***error!***'; say; say arg(1); say; exit 13
/*──────────────────────────────────────────────────────────────────────────────────────*/
\$: procedure; showDig=8 /*only show eight significant digits.*/
_=format(arg(1), , showDig) / 1 /*format number 8 digs past dec, point.*/
p=pos(., _); L=length(_) /*find position of the decimal point. */
/* [↓] align integers with FP numbers.*/
if p==0 then _=_ || left('',5+showDig+1) /*the number has no decimal point. */
else _=_ || left('',5+showDig-L+p) /* " " " a " " */
return right(_, 50) /*return the re-formatted number (arg).*/
/*──────────────────────────────────────────────────────────────────────────────────────*/
name: parse arg y /*abbreviations ──► shortname.*/
yU=translate(y, 'eE', "éÉ"); upper yU /*uppercase the temperature unit*/
if left(yU, 7)=='DEGREES' then yU=substr(yU, 8) /*redundant "degrees" after #? */
if left(yU, 6)=='DEGREE' then yU=substr(yU, 7) /* " "degree" " " */
yU=strip(yU) /*elide blanks at front and back*/
_=length(yU) /*obtain the yU length. */
if right(yU, 1)=='S' & _>1 then yU=left(yU, _ -1) /*elide trailing plural, if any.*/
select /*abbreviations ──► shortname.*/
abbrev('CENTRIGRADE', yU) |, /* 50% misspelled.*/
abbrev('CETIGRADE' , yU) |, /* 50% misspelled.*/
abbrev('CENTESIMAL' , yU) |,
abbrev('CELCIU' , yU) |, /* 82% misspelled.*/
abbrev('CELCIOU' , yU) |, /* 4% misspelled.*/
abbrev('CELCUI' , yU) |, /* 4% misspelled.*/
abbrev('CELSUI' , yU) |, /* 2% misspelled.*/
abbrev('CELCEU' , yU) |, /* 2% misspelled.*/
abbrev('CELCU' , yU) |, /* 2% misspelled.*/
abbrev('CELISU' , yU) |, /* 1% misspelled.*/
abbrev('CELSU' , yU) |, /* 1% misspelled.*/
abbrev('CELSIU' , yU) then sn='CELSIUS'
when abbrev('DELISLE' , yU,2) then sn='DELISLE'
when abbrev('FARENHEIT' , yU) |, /* 39% misspelled.*/
abbrev('FARENHEIGHT', yU) |, /* 15% misspelled.*/
abbrev('FARENHITE' , yU) |, /* 6% misspelled.*/
abbrev('FARENHIET' , yU) |, /* 3% misspelled.*/
abbrev('FARHENHEIT' , yU) |, /* 3% misspelled.*/
abbrev('FARINHEIGHT', yU) |, /* 2% misspelled.*/
abbrev('FARENHIGHT' , yU) |, /* 2% misspelled.*/
abbrev('FAHRENHIET' , yU) |, /* 2% misspelled.*/
abbrev('FERENHEIGHT', yU) |, /* 2% misspelled.*/
abbrev('FEHRENHEIT' , yU) |, /* 2% misspelled.*/
abbrev('FERENHEIT' , yU) |, /* 2% misspelled.*/
abbrev('FERINHEIGHT', yU) |, /* 1% misspelled.*/
abbrev('FARIENHEIT' , yU) |, /* 1% misspelled.*/
abbrev('FARINHEIT' , yU) |, /* 1% misspelled.*/
abbrev('FARANHITE' , yU) |, /* 1% misspelled.*/
abbrev('FAHRENHEIT' , yU) then sn='FAHRENHEIT'
when abbrev('KALVIN' , yU) |, /* 27% misspelled.*/
abbrev('KERLIN' , yU) |, /* 18% misspelled.*/
abbrev('KEVEN' , yU) |, /* 9% misspelled.*/
abbrev('KELVIN' , yU) then sn='KELVIN'
when abbrev('NEUTON' , yU) |, /*100% misspelled.*/
abbrev('NEWTON' , yU) then sn='NEWTON'
when abbrev('RANKINE' , yU, 1) then sn='RANKINE'
when abbrev('REAUMUR' , yU, 2) then sn='REAUMUR'
when abbrev('ROEMER' , yU, 2) |,
abbrev('ROMER' , yU, 2) then sn='ROMER'
otherwise call serr 'illegal temperature scale:' y
end /*select*/
return

output   when using the input of:     98.6F to C,   -40C, 0 c (water freezes),   37C (body temp),   100 C (water boils),   21 degrees Kelvin,   0 K (outer space?)

───────────────────────────────────────────────────────────────────  98.6F to C
37               Celsius
─────────────────────────────────────────────────────────────────────────  -40C
-40               Celsius
210               Delisle
-40               Fahrenheit
233.15            kelvins
-13.2             Newton
419.67            Rankine
-32               Reaumur
-3.16666667      Romer
──────────────────────────────────────────────────────────  0 c (water freezes)
0               Celsius
150               Delisle
32               Fahrenheit
273.15            kelvins
0               Newton
491.67            Rankine
0               Reaumur
7.5             Romer
──────────────────────────────────────────────────────────────  37C (body temp)
37               Celsius
94.5             Delisle
98.6             Fahrenheit
310.15            kelvins
12.21            Newton
558.27            Rankine
29.6             Reaumur
17.36666667      Romer
──────────────────────────────────────────────────────────  100 C (water boils)
100               Celsius
0               Delisle
212               Fahrenheit
373.15            kelvins
33               Newton
671.67            Rankine
80               Reaumur
34.16666667      Romer
────────────────────────────────────────────────────────────  21 degrees Kelvin
-252.15            Celsius
528.225           Delisle
-421.87            Fahrenheit
21               kelvins
-83.2095          Newton
37.8             Rankine
-201.72            Reaumur
-59.74            Romer
───────────────────────────────────────────────────────────  0 K (outer space?)
-273.15            Celsius
559.725           Delisle
-459.67            Fahrenheit
0               kelvins
-90.1395          Newton
0               Rankine
-218.52            Reaumur
-65.34            Romer

[Actually, water freezes at 0.000089º C,   and boils at 99.974º C.]

### unabridged

The REXX program can be seen at   ──►   Temperature conversion/REXX

This REXX version supports   58   temperature scales.

Scientific note:   at temperatures above   1 Planck,   quantum gravitational effects become relevant, and current physical theory breaks down because there is a lack of a theory of quantum gravity.

See the Wikipedia article:     Planck temperature.

output   when using the input of:     0 Fahrenheit

─────────────────────────────────────────────────────────────────  0 Fahrenheit
255.37222222      Absolute
47.67781999      Amonton
-1               Barnsdorf
-14.35292957      Beaumuir
-21.81664121      Benart
-23.8667          Bergen
-15               Brisson
-17.77777778      Celsius
1.67777462      Cimento
992.00031276      Cruquius
-21.85185185      Dalence
-21.57297438      Dalton
-7.70075111      Daniell
3               De la Hire
-6.48011         De la Ville
176.66666667      Delisle
133.67787165      Delisle OLD
-14               De Luc
-17.5             De Lyon
174.84536082      De Revillas
72.4978          Derham
-1.5             Derham OLD
-23.7037          De Villeneuve
-17.6666          De Suede
-37.9202          Du Crest
1.37508701      Edinburgh
0.02200631      electron volts
0               Fahrenheit
-89.2727          Fahrenheit OLD
-7.42857         Florentine large
-73.9736          Florentine Magnum
1.38571         Florentine small
-83.97491258      Fowler
-73.459919        Frick
-10               gas mark
16               Goubert
-26.66666667      Hales
10.000375        Hanow
-122.44444444      Hauksbee
210.7777          Jacobs-Holborn
255.37222222      kelvins
235.222           Leiden
-5.86666667      Newton
16               Oertel
1.80241583E-30  Planck
459.67            Rankine
-14.22222222      Reaumur
3.39999781      Richter
-2.13333333      Rinaldini
2.75925926      Romer
866.84368889      Rosenthal
122.82            Royal Society of London
15.74512902      Segredo
-44.20787188      Saint-Patrice
-5.71111111      Stufe
-29.00074174      Sulzer
-0.59259259      Thermostat
-11.53701838      Wedgwood

output   when using the input of:     0 kelvin

─────────────────────────────────────────────────────────────────────  0 kelvin
0               Absolute
-7.22722761      Amonton
-68.03513851      Barnsdorf
-220.52827751      Beaumuir
-342.38766729      Benart
-452.89203333      Bergen
-230.4703125       Brisson
-273.15            Celsius
-168.14455975      Cimento
-131.1567538       Cruquius
-192.1             Dalence
-infinity         Dalton
-70.91221875      Daniell
-249.38503119      De la Hire
-459.51615256      De la Ville
559.725           Delisle
423.52554742      Delisle OLD
-215.105625        De Luc
-268.88203125      De Lyon
553.95463918      De Revillas
-104.21950913      Derham
-154.72333333      Derham OLD
-364.20011547      De Villeneuve
-272.01733333      De Suede
-337.00724352      Du Crest
-97.38098225      Edinburgh
0               electron volts
-459.67            Fahrenheit
-925.03633636      Fahrenheit OLD
-401.43149281      Florentine large
-766.5078253       Florentine Magnum
-172.63202157      Florentine small
-801.84922875      Fowler
-650.345769        Frick
-28.3868          gas mark
-213.835           Goubert
-409.725           Hales
-420.93486331      Hanow
-760.875           Hauksbee
-1,602.36507778      Jacobs-Holborn
0               kelvins
-20.15022222      Leiden
-90.1395          Newton
-213.835           Oertel
0               Planck
0               Rankine
-218.52            Reaumur
-206.32443969      Richter
-32.778           Rinaldini
-65.34            Romer
-11.63675556      Rosenthal
757.1646          Royal Society of London
-1,194.54976303      Segredo
-219.57210928      Saint-Patrice
-15.926           Stufe
-430.12644531      Sulzer
-9.105           Thermostat
-21.81059691      Wedgwood

## Ring

k = 21.0 c = 0 r = 0 f = 0
convertTemp(k)
see "Kelvin : " + k + nl +
"Celcius : " + c + nl +
"Rankine : " + r + nl +
"Fahrenheit : " + f + nl

func convertTemp k
c = k - 273.15
r = k * 1.8
f = r - 459.67

## Ruby

module TempConvert

FROM_TEMP_SCALE_TO_K =
{'kelvin' => lambda{|t| t},
'celsius' => lambda{|t| t + 273.15},
'fahrenheit' => lambda{|t| (t + 459.67) * 5/9.0},
'rankine' => lambda{|t| t * 5/9.0},
'delisle' => lambda{|t| 373.15 - t * 2/3.0},
'newton' => lambda{|t| t * 100/33.0 + 273.15},
'reaumur' => lambda{|t| t * 5/4.0 + 273.15},
'roemer' => lambda{|t| (t - 7.5) * 40/21.0 + 273.15}}

TO_TEMP_SCALE_FROM_K =
{'kelvin' => lambda{|t| t},
'celsius' => lambda{|t| t - 273.15},
'fahrenheit' => lambda{|t| t * 9/5.0 - 459.67},
'rankine' => lambda{|t| t * 9/5.0},
'delisle' => lambda{|t| (373.15 - t) * 3/2.0},
'newton' => lambda{|t| (t - 273.15) * 33/100.0},
'reaumur' => lambda{|t| (t - 273.15) * 4/5.0},
'roemer' => lambda{|t| (t - 273.15) * 21/40.0 + 7.5}}

SUPPORTED_SCALES = FROM_TEMP_SCALE_TO_K.keys.join('|')

def self.method_missing(meth, *args, &block)
if valid_temperature_conversion?(meth) then
convert_temperature(meth, *args)
else
super
end
end

def self.respond_to_missing?(meth, include_private = false)
valid_temperature_conversion?(meth) || super
end

def self.valid_temperature_conversion?(meth)
!!(meth.to_s =~ /(#{SUPPORTED_SCALES})_to_(#{SUPPORTED_SCALES})/)
end

def self.convert_temperature(meth, temp)
from_scale, to_scale = meth.to_s.split("_to_")
return temp.to_f if from_scale == to_scale # no kelvin roundtrip
TO_TEMP_SCALE_FROM_K[to_scale].call(FROM_TEMP_SCALE_TO_K[from_scale].call(temp)).round(2)
end

end

Converts all eight scales to any other scale, by means of method_missing.

Usage:

TempConvert.kelvin_to_celsius 100 #=> -173.15
TempConvert.kelvin_to_fahrenheit 100 #=> -279.67
TempConvert.kelvin_to_rankine 100 #=> 180.0
TempConvert.kelvin_to_delisle 100 #=> 409.73
TempConvert.kelvin_to_newton 100 #=> -57.14
TempConvert.kelvin_to_reaumur 100 #=> -138.52
TempConvert.kelvin_to_roemer 100 #=> -83.4

TempConvert.newton_to_celsius 100 #=> 303.03
TempConvert.newton_to_fahrenheit 100 #=> 577.45
# All 64 combinations possible

## Run BASIC

[loop]
input "Kelvin Degrees";kelvin
if kelvin <= 0 then end ' zero or less ends the program
celcius = kelvin - 273.15
fahrenheit = kelvin * 1.8 - 459.67
rankine = kelvin * 1.8
print kelvin;" kelvin is equal to ";celcius; " degrees celcius and ";fahrenheit;" degrees fahrenheit and ";rankine; " degrees rankine"
goto [loop]

## Scala

Library: Scala
object TemperatureConversion extends App {

def kelvinToCelsius(k: Double) = k + 273.15

def kelvinToFahrenheit(k: Double) = k * 1.8 - 459.67

def kelvinToRankine(k: Double) = k * 1.8

if (args.length == 1) {
try {
val kelvin = args(0).toDouble
if (kelvin >= 0) {
println(f"K \$kelvin%2.2f")
println(f"C \${kelvinToCelsius(kelvin)}%2.2f")
println(f"F \${kelvinToFahrenheit(kelvin)}%2.2f")
println(f"R \${kelvinToRankine(kelvin)}%2.2f")
} else println("%2.2f K is below absolute zero", kelvin)

} catch {
case e: NumberFormatException => System.out.println(e)
case e: Throwable => {
println("Some other exception type:")
e.printStackTrace()
}
}
} else println("Temperature not given.")
}
Output:
K  21,00
C  294,15
F  -421,87
R  37,80

## Scheme

(import (scheme base)
(scheme write))

(define (kelvin->celsius k)
(- k 273.15))

(define (kelvin->fahrenheit k)
(- (* k 1.8) 459.67))

(define (kelvin->rankine k)
(* k 1.8))

;; Run the program
(let ((k (begin (display "Kelvin  : ") (flush-output-port) (read))))
(when (number? k)
(display "Celsius  : ") (display (kelvin->celsius k)) (newline)
(display "Fahrenheit: ") (display (kelvin->fahrenheit k)) (newline)
(display "Rankine  : ") (display (kelvin->rankine k)) (newline)))

Output:
Kelvin    : 21
Celsius   : -252.14999999999998
Fahrenheit: -421.87
Rankine   : 37.800000000000004

## Seed7

\$ include "seed7_05.s7i";
include "float.s7i";

const func float: celsius (in float: kelvin) is
return kelvin - 273.15;

const func float: fahrenheit (in float: kelvin) is
return kelvin * 1.8 - 459.67;

const func float: rankine (in float: kelvin) is
return kelvin * 1.8;

const proc: main is func
local
var float: kelvin is 0.0;
begin
write("Enter temperature in kelvin: ");
writeln("K: " <& kelvin digits 2 lpad 7);
writeln("C: " <& celsius(kelvin) digits 2 lpad 7);
writeln("F: " <& fahrenheit(kelvin) digits 2 lpad 7);
writeln("R: " <& rankine(kelvin) digits 2 lpad 7);
end func;
Output:
Enter temperature in kelvin: 21.0
K:   21.00
C: -252.15
F: -421.87
R:   37.80

## Sidef

Translation of: Perl
var scale = Hash(
Celcius => Hash.new(factor => 1 , offset => -273.15 ),
Rankine => Hash.new(factor => 1.8, offset => 0 ),
Fahrenheit => Hash.new(factor => 1.8, offset => -459.67 ),
);

var kelvin = Sys.readln("Enter a temperature in Kelvin: ").to_n;
kelvin >= 0 || die "No such temperature!";

scale.keys.sort.each { |key|
printf("%12s:%8.2f\n", key, kelvin*scale{key}{:factor} + scale{key}{:offset});
}
Output:
Enter a temperature in Kelvin: 256
Celcius:  -17.15
Fahrenheit:    1.13
Rankine:  460.80

## Swift

func KtoC(kelvin : Double)->Double{

return kelvin-273.15
}

func KtoF(kelvin : Double)->Double{

return ((kelvin-273.15)*1.8)+32
}

func KtoR(kelvin : Double)->Double{

return ((kelvin-273.15)*1.8)+491.67
}

var k// input
print("\(k) Kelvin")
var c=KtoC(kelvin : k)
print("\(c) Celsius")
var f=KtoF(kelvin : k)
print("\(f) Fahrenheit")
var r=KtoR(kelvin : k)
print("\(r) Rankine")

## Tcl

proc temps {k} {
set c [expr {\$k - 273.15}]
set r [expr {\$k / 5.0 * 9.0}]
set f [expr {\$r - 459.67}]
list \$k \$c \$f \$r
}

Demonstrating:

puts -nonewline "Enter a temperature in K: "
flush stdout
lassign [temps [gets stdin]] k c f r
puts [format "K: %.2f" \$k]
puts [format "C: %.2f" \$c]
puts [format "F: %.2f" \$f]
puts [format "R: %.2f" \$r]
Output:
Enter a temperature in K: 21
K: 21.00
C: -252.15
F: -421.87
R: 37.80

## UNIX Shell

### Korn Shell

Works with: ksh
#!/bin/ksh
# Temperature conversion
typeset tt[1]=0.00 tt[2]=273.15 tt[3]=373.15
for i in {1..3}
do
((t=tt[i]))
echo \$i
echo "Kelvin: \$t K"
echo "Celsius: \$((t-273.15)) C"
echo "Fahrenheit: \$((t*18/10-459.67)) F"
echo "Rankine: \$((t*18/10)) R"
done

### bash

Works with: Bourne Again SHell
#!/bin/bash
# Temperature conversion
tt[1]=0.00; tt[2]=273.15; tt[3]=373.15
for i in {1..3}
do
t=\${tt[\$i]}
echo \$i
echo "Kelvin: \$t K"
echo "Celsius: \$(bc<<<"scale=2;\$t-273.15") C"
echo "Fahrenheit: \$(bc<<<"scale=2;\$t*18/10-459.67") F"
echo "Rankine: \$(bc<<<"scale=2;\$t*18/10") R"
done

## Ursa

decl double k
while true
out "Temp. in Kelvin? " console
set k (in double console)
out "K\t" k endl "C\t" (- k 273.15) endl console
out "F\t" (- (* k 1.8) 459.67) endl "R\t" (* k 1.8) endl endl console
end while

## VBA

Option Explicit

Sub Main_Conv_Temp()
Dim K As Single, Result As Single
K = 21
Debug.Print "Input in Kelvin  : " & Format(K, "0.00")
Debug.Print "Output in Celsius  : " & IIf(ConvTemp(Result, K, "C"), Format(Result, "0.00"), False)
Debug.Print "Output in Fahrenheit : " & IIf(ConvTemp(Result, K, "F"), Format(Result, "0.00"), False)
Debug.Print "Output in Rankine  : " & IIf(ConvTemp(Result, K, "R"), Format(Result, "0.00"), False)
Debug.Print "Output error  : " & IIf(ConvTemp(Result, K, "T"), Format(Result, "0.00"), False)
End Sub

Function ConvTemp(sngReturn As Single, Kelv As Single, InWhat As String) As Boolean
Dim ratio As Single

ConvTemp = True
ratio = 9 / 5
Select Case UCase(InWhat)
Case "C": sngReturn = Kelv - 273.15
Case "F": sngReturn = (Kelv * ratio) - 459.67
Case "R": sngReturn = Kelv * ratio
Case Else: ConvTemp = False
End Select
End Function

Output:
Input in Kelvin      : 21,00
Output in Celsius    : -252,15
Output in Fahrenheit : -421,87
Output in Rankine    : 37,80
Output error         : False

## VBScript

WScript.StdOut.Write "Enter the temperature in Kelvin:"

WScript.StdOut.WriteLine "Kelvin: " & tmp
WScript.StdOut.WriteLine "Fahrenheit: " & fahrenheit(CInt(tmp))
WScript.StdOut.WriteLine "Celsius: " & celsius(CInt(tmp))
WScript.StdOut.WriteLine "Rankine: " & rankine(CInt(tmp))

Function fahrenheit(k)
fahrenheit = (k*1.8)-459.67
End Function

Function celsius(k)
celsius = k-273.15
End Function

Function rankine(k)
rankine = (k-273.15)*1.8+491.67
End Function

Output:
C:\>cscript /nologo tmp.vbs
Enter the temperature in Kelvin:21
Kelvin: 21
Fahrenheit: -421.87
Celsius: -252.15
Rankine: 37.8000000000001

## Visual FoxPro

#DEFINE ABSZC 273.16
#DEFINE ABSZF 459.67
LOCAL k As Double, c As Double, f As Double, r As Double, n As Integer, ;
cf As String
n = SET("Decimals")
cf = SET("Fixed")
SET DECIMALS TO 2
SET FIXED ON
CLEAR
DO WHILE .T.
k = VAL(INPUTBOX("Degrees Kelvin:", "Temperature"))
IF k <= 0
EXIT
ENDIF
? "K:", k
c = k - ABSZC
? "C:", c
f = 1.8*c + 32
? "F:", f
r = f + ABSZF
? "R:", r
?
ENDDO
SET FIXED &cf
SET DECIMALS TO n
Output:
K: 21.00
C: -252.15
F: -421.87
R: 37.80

## XLISP

(DEFUN CONVERT-TEMPERATURE ()
(SETQ *FLONUM-FORMAT* "%.2f")
(DISPLAY "Enter a temperature in Kelvin.")
(NEWLINE)
(DISPLAY "> ")
(DISPLAY `(K = ,K))
(NEWLINE)
(DISPLAY `(C = ,(- K 273.15)))
(NEWLINE)
(DISPLAY `(F = ,(- (* K 1.8) 459.67)))
(NEWLINE)
(DISPLAY `(R = ,(* K 1.8))))
Output:
(CONVERT-TEMPERATURE)
Enter a temperature in Kelvin.
> 291.5
(K = 291.50)
(C = 18.35)
(F = 65.03)
(R = 524.70)

## XPL0

include c:\cxpl\codes;
real K, C, F, R;
[ChOut(0, ^K); K:= RlIn(0);
C:= K - 273.15;
ChOut(0, ^C); RlOut(0, C); CrLf(0);
F:= 1.8*C + 32.0;
ChOut(0, ^F); RlOut(0, F); CrLf(0);
R:= F + 459.67;
ChOut(0, ^R); RlOut(0, R); CrLf(0);
]
Output:
K 21
C -252.15000
F -421.87000
R   37.80000

## zkl

println("K %.2f".fmt(K));
println("F %.2f".fmt(K*1.8 - 459.67));
println("C %.2f".fmt(K - 273.15));
println("R %.2f".fmt(K*1.8));
Output:
Kelvin: 373.15
K 373.15
F 212.00
C 100.00
R 671.67

## ZX Spectrum Basic

10 REM Translation of traditional basic version
20 INPUT "Kelvin Degrees? ";k
30 IF k <= 0 THEN STOP: REM A value of zero or less will end program
40 LET c = k - 273.15
50 LET f = k * 1.8 - 459.67
60 LET r = k * 1.8
70 PRINT k; " Kelvin is equivalent to"
80 PRINT c; " Degrees Celsius"
90 PRINT f; " Degrees Fahrenheit"
100 PRINT r; " Degrees Rankine"
110 GO TO 20