Non-decimal radices/Input
You are encouraged to solve this task according to the task description, using any language you may know.
It is common to have a string containing a number written in some format, with the most common ones being decimal, hexadecimal, octal and binary. Such strings are found in many places (user interfaces, configuration files, XML data, network protocols, etc.)
This task requires parsing of such a string (which may be assumed to contain nothing else) using the language's built-in facilities if possible. Parsing of decimal strings is required, parsing of other formats is optional but should be shown (i.e., if the language can parse in base-19 then that should be illustrated).
The solutions may assume that the base of the number in the string is known. In particular, if your language has a facility to guess the base of a number by looking at a prefix (e.g. "0x" for hexadecimal) or other distinguishing syntax as it parses it, please show that.
The reverse operation is in task Non-decimal radices/Output
For general number base conversion, see Non-decimal radices/Convert.
Ada
Ada supports the input format <BASE>#<VALUE>#, for example 16#AF42# or 2#1010110# or 8#777#. This can be used for input through Ada.Text_IO.Integer_IO or for conversion through Integer'Value. More details on this format can be found here: Ada 2005 Reference Manual - 2.4.2 Based Literals.
Limited to Bases 2 to 16.
Works with Float values, too.
numbers.adb: <lang Ada>with Ada.Text_IO; procedure Numbers is
package Int_IO is new Ada.Text_IO.Integer_IO (Integer); package Float_IO is new Ada.Text_IO.Float_IO (Float);
begin
Int_IO.Put (Integer'Value ("16#ABCF123#"));
Ada.Text_IO.New_Line;
Int_IO.Put (Integer'Value ("8#7651#"));
Ada.Text_IO.New_Line;
Int_IO.Put (Integer'Value ("2#1010011010#"));
Ada.Text_IO.New_Line;
Float_IO.Put (Float'Value ("16#F.FF#E+2"));
Ada.Text_IO.New_Line;
end Numbers;</lang>
Output:
180154659
4009
666
4.09500E+03
Aime
<lang aime>o_integer(alpha("f4240", 16)); o_byte('\n'); o_integer(alpha("224000000", 5)); o_byte('\n'); o_integer(alpha("11110100001001000000", 2)); o_byte('\n');
o_integer(alpha("03641100", 0)); o_byte('\n'); o_integer(alpha("0xf4240", 0)); o_byte('\n');</lang>
ALGOL 68
<lang algol68>main: (
FILE fbuf; STRING sbuf;
OP FBUF = (STRING in sbuf)REF FILE: ( sbuf := in sbuf; associate(fbuf, sbuf); fbuf );
BITS num;
getf(FBUF("0123459"), ($10r7d$, num));
printf(($gl$, ABS num)); # prints 123459 #
getf(FBUF("abcf123"), ($16r7d$, num));
printf(($gl$, ABS num)); # prints 180154659 #
getf(FBUF("7651"), ($8r4d$, num));
printf(($gl$, ABS num)); # prints 4009 #
getf(FBUF("1010011010"), ($2r10d$, num));
printf(($gl$, ABS num)) # prints 666 #
)</lang> Output:
+123459
+180154659
+4009
+666
AutoHotkey
There is no built in support for generic base parsing.
Please see Number base conversion
BBC BASIC
<lang bbcbasic> REM VAL parses decimal strings:
PRINT VAL("0")
PRINT VAL("123456789")
PRINT VAL("-987654321")
REM EVAL can be used to parse binary and hexadecimal strings:
PRINT EVAL("%10101010")
PRINT EVAL("%1111111111")
PRINT EVAL("&ABCD")
PRINT EVAL("&FFFFFFFF")</lang>
Output:
0
123456789
-987654321
170
1023
43981
-1
C
In addition to strtol() described in the Number base conversion task, you could also use the scanf family of functions to parse un-prefixed hexadecimal, decimal, and octal numbers:
<lang c>#include <stdio.h>
int main() {
int num;
sscanf("0123459", "%d", &num);
printf("%d\n", num); /* prints 123459 */
sscanf("abcf123", "%x", &num);
printf("%d\n", num); /* prints 180154659 */
sscanf("7651", "%o", &num);
printf("%d\n", num); /* prints 4009 */
/* binary not supported */
return 0;
}</lang>
The strtol() function can also parse prefixed hexadecimal, octal, and decimal strings based on the prefix, when passed a base of 0:
<lang c>#include <stdio.h>
- include <stdlib.h>
- include <assert.h>
int main() {
int num; char *endptr;
num = strtol("123459", &endptr, 0);
assert(*endptr == '\0');
printf("%d\n", num); /* prints 123459 */
num = strtol("0xabcf123", &endptr, 0);
assert(*endptr == '\0');
printf("%d\n", num); /* prints 180154659 */
num = strtol("07651", &endptr, 0);
assert(*endptr == '\0');
printf("%d\n", num); /* prints 4009 */
/* binary not supported */
return 0;
}</lang>
C#
<lang csharp>using System;
class Program {
static void Main()
{
var value = "100";
var fromBases = new[] { 2, 8, 10, 16 };
var toBase = 10;
foreach (var fromBase in fromBases)
{
Console.WriteLine("{0} in base {1} is {2} in base {3}",
value, fromBase, Convert.ToInt32(value, fromBase), toBase);
}
}
}</lang> Output: <lang>100 in base 2 is 4 in base 10 100 in base 8 is 64 in base 10 100 in base 10 is 100 in base 10 100 in base 16 is 256 in base 10</lang>
C++
<lang cpp>#include <iostream>
- include <sstream>
int main() {
int num;
std::istringstream("0123459") >> num;
std::cout << num << std::endl; // prints 123459
std::istringstream("0123459") >> std::dec >> num;
std::cout << num << std::endl; // prints 123459
std::istringstream("abcf123") >> std::hex >> num;
std::cout << num << std::endl; // prints 180154659
std::istringstream("7651") >> std::oct >> num;
std::cout << num << std::endl; // prints 4009
// binary not supported
return 0;
}</lang>
Common Lisp
<lang lisp>(parse-integer "abc" :radix 20 :junk-allowed t) ; => 4232</lang>
If :radix is omitted, it defaults to 10. If :junk-allowed is omitted, it defaults to nil, causing #'parse-integer to signal an error of type parse-error rather than just returning nil whenever the input string isn't a numeral possibly surrounded by whitespace.
D
<lang d>import std.stdio, std.conv;
void main() {
immutable text = "100";
foreach (base; 2 .. 21)
writefln("String '%s' in base %d is %d in base 10" ,
text, base, to!int(text, base));
}</lang>
- Output:
String '100' in base 2 is 4 in base 10 String '100' in base 3 is 9 in base 10 String '100' in base 4 is 16 in base 10 String '100' in base 5 is 25 in base 10 String '100' in base 6 is 36 in base 10 String '100' in base 7 is 49 in base 10 String '100' in base 8 is 64 in base 10 String '100' in base 9 is 81 in base 10 String '100' in base 10 is 100 in base 10 String '100' in base 11 is 121 in base 10 String '100' in base 12 is 144 in base 10 String '100' in base 13 is 169 in base 10 String '100' in base 14 is 196 in base 10 String '100' in base 15 is 225 in base 10 String '100' in base 16 is 256 in base 10 String '100' in base 17 is 289 in base 10 String '100' in base 18 is 324 in base 10 String '100' in base 19 is 361 in base 10 String '100' in base 20 is 400 in base 10
E
<lang e>? __makeInt("200", 16)
- value: 512
? __makeInt("200", 10)
- value: 200</lang>
Elixir
base: 2 .. 36 <lang elixir>iex(1)> String.to_integer("1000") 1000 iex(2)> String.to_integer("1000",2) 8 iex(3)> String.to_integer("1000",8) 512 iex(4)> String.to_integer("1000",16) 4096 iex(5)> String.to_integer("ffff",16) 65535</lang>
Erlang
My interpretation of the task description is that I can state that the base (here: 17) can be 2..36, without having to show one example of each.
- Output:
<12> erlang:list_to_integer("ffff", 17).
78300
F#
<lang fsharp>let value = "100" let fromBases = [ 2; 8; 10; 16 ] let values = Seq.initInfinite (fun i -> value) Seq.zip fromBases (Seq.zip values fromBases |> Seq.map (System.Convert.ToInt32)) |> Seq.iter (
fun (fromBase, valueFromBaseX) ->
printfn "%s in base %i is %i in base 10" value fromBase valueFromBaseX)</lang>
- Output:
100 in base 2 is 4 in base 10 100 in base 8 is 64 in base 10 100 in base 10 is 100 in base 10 100 in base 16 is 256 in base 10
Factor
Bases from 2 to 16 are supported through the generic base> word (see online docs [1]) but 4 functions are defined for the most used cases:
( scratchpad ) "ff" hex> . ! base 16 255 ( scratchpad ) "777" oct> . ! base 8 511 ( scratchpad ) "1111" bin> . ! base 2 15 ( scratchpad ) "99" string>number . ! base 10 99
Note that these words are very simple : for example, here's oct> : <lang factor>IN: math.parser
- oct> ( str -- n/f ) 8 base> ; inline</lang>
Also, fractions are handled transparently :
( scratchpad ) "1+F/2" hex> . 8+1/2
Hex floats are supported, anything else is taken as base 10 :
( scratchpad ) "ff.f" hex> . 255.9375 ( scratchpad ) "11.1101" bin> . 11.1101
Forth
Arbitrary base 2-36 parsing is supported by the same mechanism as decimal parsing: set the user variable BASE to the desired base, then scan the number. There are two convenience words for setting the base to DECIMAL or HEX. <lang forth>: parse# ( str len -- u true | false )
0. 2SWAP DUP >R >NUMBER NIP NIP R> <> DUP 0= IF NIP THEN ;
- base# ( str len base -- u true | false )
BASE @ >R BASE ! parse# R> BASE ! ;</lang>
Fortran
<lang fortran>program Example
implicit none
integer :: num character(32) :: str
str = "0123459" read(str, "(i10)") num ! Decimal write(*,*) num ! Prints 123459
str = "abcf123" read(str, "(z8)") num ! Hexadecimal write(*,*) num ! Prints 180154659
str = "7651" read(str, "(o11)") num ! Octal write(*,*) num ! Prints 4009
str = "1010011010" read(str, "(b32)") num ! Binary write(*,*) num ! Prints 666
end program</lang>
FreeBASIC
FreeBASIC has built-in string to integer conversion functions which automatically recognize numbers in hexadecimal, decimal, octal or binary format provided that they are prefixed by &H, (nothing), &O and &B respectively. Here's an example: <lang freebasic>' FB 1.05.0 Win64
Dim s(1 To 4) As String = {"&H1a", "26", "&O32", "&B11010"} 26 in various bases For i As Integer = 1 To 4
Print s(i); Tab(9); "="; CInt(s(i))
Next
Sleep</lang>
- Output:
&H1a = 26 26 = 26 &O32 = 26 &B11010 = 26
Go
<lang go>package main
import (
"fmt" "math/big" "strconv"
)
func main() {
// package strconv: the most common string to int conversion,
// base 10 only.
x, _ := strconv.Atoi("13")
fmt.Println(x)
// ParseInt handles arbitrary bases from 2 to 36, and returns
// a result of the requested size (64 bits shown here.)
// If the base argument is zero the base is determined by prefix
// as with math/big below.
x64, _ := strconv.ParseInt("3c2", 19, 64)
fmt.Println(x64)
// package fmt: allows direct conversion from strings, standard
// input, or from an io.Reader (file, buffer, etc) to integer types
// for bases 2, 8, 10, and 16 or to any type that implements the
// fmt.Scanner interface (e.g. a big.Int).
// (Fscanf and Scanf are more common for reading from
// an io.Reader or stdin than Sscanf for reading from strings.)
fmt.Sscanf("1101", "%b", &x)
fmt.Println(x)
fmt.Sscanf("15", "%o", &x)
fmt.Println(x)
fmt.Sscanf("13", "%d", &x)
fmt.Println(x)
fmt.Sscanf("d", "%x", &x)
fmt.Println(x)
// package math/big: allows conversion from string to big integer.
// any base from 2 to 36 can be specified as second parameter.
var z big.Int
z.SetString("111", 3)
fmt.Println(&z)
// if second parameter is 0, base is determined by prefix, if any
z.SetString("0b1101", 0) // 0b -> base 2
fmt.Println(&z)
z.SetString("015", 0) // 0 -> base 8
fmt.Println(&z)
z.SetString("13", 0) // no prefix -> base 10
fmt.Println(&z)
z.SetString("0xd", 0) // 0x -> base 16
fmt.Println(&z)
// As mentioned, a big.Int (or any type implementing fmt.Scanner)
// can also be use with any of the fmt scanning functions.
fmt.Sscanf("15", "%o", &z)
fmt.Println(&z)
}</lang> Output is all 13s.
Haskell
Haskell's read can parse strings with the same prefix used for literals in Haskell (0x or 0X for hex, 0o or 0O for octal): <lang haskell>Prelude> read "123459" :: Integer 123459 Prelude> read "0xabcf123" :: Integer 180154659 Prelude> read "0o7651" :: Integer 4009</lang>
HicEst
<lang HicEst>READ(Text="123459 ", Format="i10") dec ! 123459 READ(Text=" abcf123 ", Format="Z10") hex ! 180154659 READ(Text=" 7651 ", Format="o10") oct ! 4009 READ(Text=" 101011001", Format="B10.10") bin ! 345</lang>
Icon and Unicon
Icon allows numbers to be defined as 'root' + "R" + 'number', where 'root' is a base from 2 to 36, and 'number' is a string of digits or letters, using 'A' to 'Z' as appropriate for the base; case is ignored. Strings are automatically parsed into numbers when needed, using the procedure 'integer'.
<lang Icon> procedure convert (str)
write (left(str, 10) || " = " || integer(str))
end
procedure main ()
convert (" 2r1001")
convert (" 8r7135")
convert ("16rABC1234")
convert ("36r1Z")
write ("2r1001" + "36r1Z") # shows type conversion, string->integer
end </lang>
Output:
2r1001 = 9 8r7135 = 3677 16rABC1234 = 180097588 36r1Z = 71 80
J
Solution 1:<lang j> baseN=: (, 'b'&,)&.":</lang> Solution 2 (input sanitizing):<lang j> baseN=: 0&".@,&": 'b' , ] NB. Use if the source of the non-decimal "numbers" is not trustworthy</lang> Example:<lang j> 16 baseN 'abcf123' 180154659
8 baseN '7651'
4009
10 baseN '123459'
123459</lang> Note: J also provides builtin support for numeric literals of an arbitrary base. The format is radixbdigits (where radix is specified in base 10). The one restriction is that you cannot use digits larger than 36 ('z'):<lang j> 16babcf123 8b7651 10b123459 180154659 4009 123459</lang>
However you can use digits larger than the radix:
<lang j> 2bhelloworld 17955</lang>
And you can use bases where not all digits are representable:
<lang j> 1000bogus 24016030028</lang>
Letters used for digits have base 10 values ranging from 10 (a) to 35 (z).
Java
You must know the base that the String is in before you scan it. Create a Scanner in the usual way, but then set its radix to that base (obviously, the default is 10): <lang java5>Scanner sc = new Scanner(System.in); //or any other InputStream or String sc.useRadix(base); //any number from Character.MIN_RADIX (2) to CHARACTER.MAX_RADIX (36) sc.nextInt(); //read in a value</lang> Later you can call sc.reset() or sc.useRadix(10) to undo this change.
Another option using the Integer class: <lang java>int number = Integer.parseInt(stringNum, base);</lang> The base here has the same restrictions as the Scanner example. A similar method is available in the Long class. Use no second argument for base 10.
If you have a prefixed string ("0x", "0X", or "#" for hex; "0" for octal; otherwise decimal), you can use the .decode() utility method to parse the number based on the base indicated by the prefix (note: this returns an Integer object, not a primitive int): <lang java>Integer.decode("0xabcf123"); // hex Integer.decode("07651"); // octal Integer.decode("123459"); // decimal</lang> Long, Short, and Byte also have a .decode() method, to decode to the appropriate number object type.
JavaScript
For base 10 and 16 ("0x"-prefixed), (but not 8), it is fastest to parse strings using the unary plus (+) operator: <lang javascript>+"0123459"; // 123459 +"0xabcf123"; // 180154659
// also supports negative numbers, but not for hex: +"-0123459"; // -123459 +"-0xabcf123"; // NaN</lang> See http://www.jibbering.com/faq/notes/type-conversion/#tcNumber for more information.
The parseInt(string,radix) core function is the reverse of the number.toString(radix) method. The following is taken from Mozilla's JavaScript 1.5 reference.
<lang javascript>parseInt(" 0xF", 16); parseInt(" F", 16); parseInt("17", 8); parseInt(021, 8); parseInt("015", 10); parseInt(15.99, 10); parseInt("FXX123", 16); parseInt("1111", 2); parseInt("15*3", 10); parseInt("15e2", 10); parseInt("15px", 10); parseInt("12", 13);</lang>
The following examples all return NaN:
<lang javascript>parseInt("Hello", 8); // Not a number at all parseInt("546", 2); // Digits are not valid for binary representations</lang>
The following examples all return -15:
<lang javascript>parseInt("-F", 16); parseInt("-0F", 16); parseInt("-0XF", 16); parseInt(-10, 16); parseInt(-15.1, 10) parseInt(" -17", 8); parseInt(" -15", 10); parseInt("-1111", 2); parseInt("-15e1", 10); parseInt("-12", 13);</lang>
The following example returns 224:
<lang javascript>parseInt("0e0", 16);</lang>
Although it is optional, most implementations interpret a numeric string beginning with a leading '0' as octal. The following may have an octal result.
<lang javascript>parseInt("0e0"); // 0
parseInt("08"); // 0, '8' is not an octal digit.</lang>Julia
<lang julia># Version 5.2 txt = "100" for base = 2:21
base10 = parse(Int, txt, base)
println("String $txt in base $base is $base10 in base 10")
end </lang> If not specify the base it will figure out the base from the prefix <lang julia> @show parse(Int, "123459") @show parse(Int, "0xabcf123") @show parse(Int, "0o7651") @show parse(Int, "0b101011001") </lang>
- Output:
String 100 in base 2 is 4 in base 10 String 100 in base 3 is 9 in base 10 String 100 in base 4 is 16 in base 10 String 100 in base 5 is 25 in base 10 String 100 in base 6 is 36 in base 10 String 100 in base 7 is 49 in base 10 String 100 in base 8 is 64 in base 10 String 100 in base 9 is 81 in base 10 String 100 in base 10 is 100 in base 10 String 100 in base 11 is 121 in base 10 String 100 in base 12 is 144 in base 10 String 100 in base 13 is 169 in base 10 String 100 in base 14 is 196 in base 10 String 100 in base 15 is 225 in base 10 String 100 in base 16 is 256 in base 10 String 100 in base 17 is 289 in base 10 String 100 in base 18 is 324 in base 10 String 100 in base 19 is 361 in base 10 String 100 in base 20 is 400 in base 10 String 100 in base 21 is 441 in base 10 parse(Int,"123459") = 123459 parse(Int,"0xabcf123") = 180154659 parse(Int,"0o7651") = 4009 parse(Int,"0b101011001") = 345
Kotlin
<lang scala>// version 1.1.2
fun main(args: Array<String>) {
val s = "100"
val bases = intArrayOf(2, 8, 10, 16, 19, 36)
for (base in bases)
println("$s in base ${"%2d".format(base)} is ${s.toInt(base)}")
}</lang>
- Output:
100 in base 2 is 4 100 in base 8 is 64 100 in base 10 is 100 100 in base 16 is 256 100 in base 19 is 361 100 in base 36 is 1296
Lua
Lua supports bases between 2 and 36. <lang lua>print( tonumber("123") ) print( tonumber("a5b0", 16) ) print( tonumber("011101", 2) ) print( tonumber("za3r", 36) )</lang>
Mathematica
<lang Mathematica>19^^91g5dcg2h6da7260a9f3c4a ->123456789012345678901234567890
2^^11110001001000000 ->123456</lang>
MATLAB / Octave
<lang MATLAB>val = sscanf('11 11 11','%d %o %x')</lang> Output:
val =
11
9
17
Nim
<lang nim>import strutils
echo parseInt "10" # 10
echo parseHexInt "0x10" # 16 echo parseHexInt "10" # 16
echo parseOctInt "0o120" # 80 echo parseOctInt "120" # 80</lang> Output:
10 16 16 80 80
OCaml
The int_of_string function can parse hexadecimal, octal, and binary numbers that have the same prefix that is used to specify OCaml constants ("0x", "0o", and "0b", respectively):
<lang ocaml># int_of_string "123459";;
- : int = 123459
- int_of_string "0xabcf123";;
- : int = 180154659
- int_of_string "0o7651";;
- : int = 4009
- int_of_string "0b101011001";;
- : int = 345</lang>
The Int32.of_string, Int64.of_string, and Nativeint.of_string functions also can understand the above prefixes when parsing into their appropriate types.
Starting in OCaml 4.02, the Big_int.big_int_of_string and Num.num_of_string functions also understand these prefixes.
You could also use the Scanf module to parse un-prefixed hexadecimal, decimal, and octal numbers (binary not supported):
<lang ocaml># Scanf.sscanf "123459" "%d" (fun x -> x);;
- : int = 123459
- Scanf.sscanf "abcf123" "%x" (fun x -> x);;
- : int = 180154659
- Scanf.sscanf "7651" "%o" (fun x -> x);;
- : int = 4009</lang>
Oz
String.toInt understands the usual prefixes. If a string cannot be parsed, an exception will be thrown.
<lang oz>{String.toInt "42"} %% decimal
= {String.toInt "0x2a"} %% hexadecimal
= {String.toInt "052"} %% octal
= {String.toInt "0b101010"} %% binary</lang>
PARI/GP
Binary conversion is built in to PARI/GP, this script can convert from bases2-36 to bases 2-36. I've had help with this script at http:\\mersenneforums.org . The main flaw in this script I see is that it doesn't allow 36^x-1 type strings, I'll have to add that on later. <lang parigp>convert(numb1,b1,b2)={
my(B=["0","1","2","3","4","5","6","7","8","9","a","b","c","d","e","f","g","h","i","j","k","l","m","n","o","p","q","r","s","t","u","v","w","x","y","z"],a=0,c="");
numb1=Vec(Str(numb1));
forstep(y=#numb1,1,-1,
for(x=1,b1,
if(numb1[y]==B[x],
a=a+(x-1)*b1^(#numb1-y)
)
)
);
until(a/b2==0,
c=concat(B[a%b2+1],c);
a=a\b2
);
c
};</lang>
Note that version 2.8.0+ supports hexadecimal (0x1ff) and binary (0b10101) inputs. Further, it can accept generic input as a vector:
<lang parigp>fromdigits([1,15,15],16)</lang>
Perl
The hex() function parses hexadecimal strings. The oct() function parses octal strings, as well as hexadecimal, octal, or binary strings with the appropriate prefix ("0x", "0", and "0b", respectively). There is no need to parse decimal strings because in Perl decimal strings and numbers are interchangeable. <lang perl>my $dec = "0123459"; my $hex_noprefix = "abcf123"; my $hex_withprefix = "0xabcf123"; my $oct_noprefix = "7651"; my $oct_withprefix = "07651"; my $bin_withprefix = "0b101011001";
print 0 + $dec, "\n"; # => 123459 print hex($hex_noprefix), "\n"; # => 180154659 print hex($hex_withprefix), "\n"; # => 180154659 print oct($hex_withprefix), "\n"; # => 180154659 print oct($oct_noprefix), "\n"; # => 4009 print oct($oct_withprefix), "\n"; # => 4009 print oct($bin_withprefix), "\n"; # => 345
- nothing for binary without prefix</lang>
Perl 6
By default, all strings of digits are parsed as base 10 numbers, including those with a leading zero. Numbers with a prefix 0b, 0o, 0d or 0x are parsed as binary, octal, decimal or hexadecimal respectively. <lang perl6>say 0b11011; # -> 27 say 0o11011; # -> 4617 say 0d11011; # -> 11011 say 0x11011; # -> 69649</lang>
Additionally, there are built-in adverbial prefix operators to parse strings of "digits" of radix 2 through radix 36 into decimal. They will fail with a runtime error if they are fed a digit that is not valid in that radix. <lang perl6>my $n = '11011';
say :2($n); # -> 27 say :3($n); # -> 112 say :4($n); # -> 325 say :5($n); # -> 756 say :6($n); # -> 1519 say :7($n); # -> 2752 say :8($n); # -> 4617 say :9($n); # -> 7300 say :10($n); # -> 11011 say :11($n); # -> 15984 say :12($n); # -> 22477 say :13($n); # -> 30772 say :14($n); # -> 41175 say :15($n); # -> 54016 say :16($n); # -> 69649 say :17($n); # -> 88452 say :18($n); # -> 110827 say :19($n); # -> 137200 say :20($n); # -> 168021 say :21($n); # -> 203764 say :22($n); # -> 244927 say :23($n); # -> 292032 say :24($n); # -> 345625 say :25($n); # -> 406276 say :26($n); # -> 474579 say :27($n); # -> 551152 say :28($n); # -> 636637 say :29($n); # -> 731700 say :30($n); # -> 837031 say :31($n); # -> 953344 say :32($n); # -> 1081377 say :33($n); # -> 1221892 say :34($n); # -> 1375675 say :35($n); # -> 1543536 say :36($n); # -> 1726309</lang>
Phix
<lang Phix>?scanf("1234","%d") ?scanf("0b10101010","%d") ?scanf("#ABCD","%d") ?scanf("#FFFFFFFF","%f") ?scanf("0xFFFFFFFF","%f") ?scanf("0o377","%o")</lang>
- Output:
{{1234}}
{{170}}
{{43981}}
{{4294967295}}
{{4294967295}}
{{255}}
Note the need for %f (if you want to get an atom rather than an integer back), and double braces (it's a list of potentially several different possible result sets/interpretations), and that scanf() works best with a few literals (esp spaces but most certainly not radix prefixes) in the format string. Finally note that while you can use "#DEADBEEF" (without the quotes, ie a fairly big hex number) in a source code file, the compiler will choke on "DEADBEEF", and likewise so too will scanf(), and the only way round that is to insert the right prefix at the right place.
PHP
The hexdec(), octdec(), bindec() function parses hexadecimal, octal, and binary strings, respectively. They skip any invalid characters, so a prefix will be ignored. There is no need to parse decimal strings because in PHP decimal strings and numbers are interchangeable. <lang php><?php echo +"0123459", "\n"; // prints 123459 echo intval("0123459"), "\n"; // prints 123459 echo hexdec("abcf123"), "\n"; // prints 180154659 echo octdec("7651"), "\n"; // prints 4009 echo bindec("101011001"), "\n"; // prints 345 ?></lang>
An undocumented feature of intval() is that it can parse prefixed strings when given the base 0: <lang php><?php echo intval("123459", 0), "\n"; // prints 123459 echo intval("0xabcf123", 0), "\n"; // prints 180154659 echo intval("07651", 0), "\n"; // prints 4009 ?></lang>
In addition, for hexadecimals, if you have a "0x"-prefixed string, you can just use it in a numeric operation, and it gets converted to the number automatically: <lang php><?php echo +"0xabcf123", "\n"; // prints 180154659
- This does not work for octals, however:
echo +"07651", "\n"; // prints 7651 ?></lang>
PL/I
<lang PL/I>declare N fixed binary; get edit (N) (A(7)); /* decimal input of 7 columns */ put skip list (N);
declare BS bit (32); get edit (BS) (B(32)); /* Binary input of 32 binary digits. */ put skip edit (BS) (B);</lang>
23 11010101010111111110000000011101
PicoLisp
<lang PicoLisp>(de parseNumber (S Base)
(let N 0
(for C (chop S)
(when (> (setq C (- (char C) `(char "0"))) 9)
(dec 'C 39) )
(setq N (+ C (* N Base))) )
N ) )
(println (parseNumber "91g5dcg2h6da7260a9f3c4a" 19))</lang> Output:
123456789012345678901234567890
PowerShell
PowerShell parses an integer prefixed with "0x" as hexadecimal. Binary and Octal conversions must use the .NET [Convert]. Here follows a (verbose) example:
<lang PowerShell>
function Select-NumberFromString
{
[CmdletBinding(DefaultParameterSetName="Decimal")]
[OutputType([PSCustomObject])]
Param
(
[Parameter(Mandatory=$true,
ValueFromPipeline=$true,
ValueFromPipelineByPropertyName=$true,
Position=0)]
[string]
$InputObject,
[Parameter(ParameterSetName="Decimal")]
[Alias("d","Dec")]
[switch]
$Decimal,
[Parameter(ParameterSetName="Hexadecimal")]
[Alias("h","Hex")]
[switch]
$Hexadecimal,
[Parameter(ParameterSetName="Octal")]
[Alias("o","Oct")]
[switch]
$Octal,
[Parameter(ParameterSetName="Binary")]
[Alias("b","Bin")]
[switch]
$Binary
)
Begin
{
switch ($PSCmdlet.ParameterSetName)
{
"Decimal" {$base = 10; $pattern = '[+-]?\b[0-9]+\b'; break}
"Hexadecimal" {$base = 16; $pattern = '\b[0-9A-F]+\b' ; break}
"Octal" {$base = 8; $pattern = '\b[0-7]+\b' ; break}
"Binary" {$base = 2; $pattern = '\b[01]+\b' ; break}
"Default" {$base = 10; $pattern = '[+-]?\b[0-9]+\b'; break}
}
}
Process
{
foreach ($object in $InputObject)
{
if ($object -match $pattern)
{
$string = $Matches[0]
}
else
{
$string = $null
}
try
{
$value = [Convert]::ToInt32($string, $base)
}
catch
{
$value = $null
}
[PSCustomObject]@{
Number = $value
String = $string
Base = $base
IsNumber = $value -is [int]
InputString = $object
}
} }
} </lang> Using a pretend file: <lang PowerShell> $file = @' John Doe abc1 K2hdystkrs Jane Doe xyz2 Ew3jtdkufy Joe Blow def3 Ouy1ttluyl '@ -split [Environment]::NewLine
$file | Select-NumberFromString -Hexadecimal | Format-Table </lang>
- Output:
Number String Base IsNumber InputString
------ ------ ---- -------- -----------
43969 abc1 16 True John Doe abc1 K2hdystkrs
16 False Jane Doe xyz2 Ew3jtdkufy
57075 def3 16 True Joe Blow def3 Ouy1ttluyl
PureBasic
<lang PureBasic> ;Val() parses integer strings
; decimal numbers have no prefix, hexadecimal needs a prefix of '$', binary needs a prefix of '%'
Val("1024102410241024") ; => 1024102410241024
Val("$10FFFFFFFF") ; => 73014444031
Val("%1000") ; => 8</lang>
Python
The int function will interpret strings as numbers expressed to some base: <lang python>>>> text = '100' >>> for base in range(2,21):
print ("String '%s' in base %i is %i in base 10"
% (text, base, int(text, base)))
String '100' in base 2 is 4 in base 10
String '100' in base 3 is 9 in base 10
String '100' in base 4 is 16 in base 10
String '100' in base 5 is 25 in base 10
String '100' in base 6 is 36 in base 10
String '100' in base 7 is 49 in base 10
String '100' in base 8 is 64 in base 10
String '100' in base 9 is 81 in base 10
String '100' in base 10 is 100 in base 10
String '100' in base 11 is 121 in base 10
String '100' in base 12 is 144 in base 10
String '100' in base 13 is 169 in base 10
String '100' in base 14 is 196 in base 10
String '100' in base 15 is 225 in base 10
String '100' in base 16 is 256 in base 10
String '100' in base 17 is 289 in base 10
String '100' in base 18 is 324 in base 10
String '100' in base 19 is 361 in base 10
String '100' in base 20 is 400 in base 10</lang>
In addition, if you give a base of 0, it will try to figure out the base from the prefix, with the same syntax as a numeric literal in Python:
Python 3.x and 2.6:
>>> int("123459", 0)
123459
>>> int("0xabcf123", 0)
180154659
>>> int("0o7651", 0)
4009
>>> int("0b101011001", 0)
345
Python 2.x:
>>> int("123459", 0)
123459
>>> int("0xabcf123", 0)
180154659
>>> int("07651", 0)
4009
Python 2.6 supports both the above formats, because it supports both types of literals.
R
<lang R># parse a string to decimal as.numeric("20") # 20
- parse a hex-string to decimal
as.numeric("0x20") # 32
- parse a string to hexadecimal
as.hexmode(as.numeric("32")) # "20"
- parse a string to octal
as.octmode(as.numeric("20")) # "24"</lang>
Racket
<lang Racket>
- lang racket
- Number literals can use #x, #o, and #b for different radices
(list 123 #x7B #o173 #b1111011)
- -> '(123 123 123 123)
- Explicit conversion of strings can use any radix up to 16
(list (string->number "123")
(string->number "123" 10)
(string->number "7B" 16)
(string->number "83" 15)
(string->number "96" 13)
(string->number "173" 8)
(string->number "11120" 3)
(string->number "1111011" 2))
- -> '(123 123 123 123 123 123 123 123)
</lang>
REXX
╔══════════════════════════════════════════════════════════════════════════════════╗ ║ In REXX, there are no numeric-type variables (integer, float, real, unsigned, ║ ║ logical, binary, complex, double, etc), only character. Everything is stored ║ ║ as a character string. Arithmetic is done almost exactly the way a schoolchild ║ ║ would perform it. Putting it simply, to add, align the two numbers up (right ║ ║ justified, with the decimal being the pivot) and add the columns up, adding the ║ ║ carries and honoring the signs. ║ ║ ║ ║ Multiplications and divisions are similarly performed. ║ ╚══════════════════════════════════════════════════════════════════════════════════╝
<lang rexx>/*REXX program demonstrates REXX's ability to handle non-decimal radices*/ a=123 /*all of these assignments are identical: */ b='123' c='1' || "2" || '3' d= 1 || 2 || 3 e= 12 || 3 f=120 + 3 g=substr(9912388,3,3) h=left(123456,3) i=right(777.123,3) j=120 + ' 3 ' k=0000000123.0000/1 /*division "normalizes the number (──► 123)*/
/*parsing of a decimal number is no */
/*different then parsing a character string*/
/*because decimal numbers ARE character */
/*strings. As such, numbers may have */
/*leading and/or trailing blanks, and in */
/*some cases, imbedded blanks (after any */
/*leading sign). */
aa=' 123 ' /*AA's exact value is different the A, */
/*but it's numerically equal to A. */
bb=123. /*the same can be said for the rest of 'em.*/ cc=+123 dd=' + 123' ee=0000123 ff=1.23e+2 gg=001.23E0002 hh=1230e-1 ii=122.999999999999999999999999999999999 /*assuming NUMERIC DIGITS 9 */ jj= +++123 kk= - -123
bingoA='10101'b /*stores a binary value. */ bingoB='10101'B /* B can be uppercase. */ bingoC='1 0101'b /*apostrophes may be used*/ bingoD="1 0101"b /*quotes may be used. */
hyoidA='deadbeaf'x /*stores a hexadecimal value.*/ hyoidB="deadbeaf"X hyoidC='dead beaf'X hyoidD='de ad be af'X hyoidE='dead be af'X hyoidF='7abc'x
/*REXX has several built-in functions */
/*(BIFs) to handle conversions of the */
/*above-mentioned "number" formats. */
cyanA=d2x(a) /*converts a decimal string to hexadecimal*/ cyanB=d2x(5612) /*converts a decimal string to hexadecimal*/
cyanD=b2x(101101) /*converts a binary string to hexadecimal*/
cyanE=b2c(101101) /*some REXXes support this, others don't. */ cyanF=c2b('copernicium') /*some REXXes support this, others don't. */
cyanG=c2d('nilla') /*converts a character string to decimal. */ cyanH=d2c(251) /*converts a decimal number to character. */
cyanI=x2d(fab) /*converts a hexadecimal string to decimal*/ cyanJ=x2c(fab) /*converts a hexadecimal string to chars. */ cyanK=x2b(fab) /*converts a hexadecimal string to binary.*/
befog=d2b(144) /*there's no dec──►binary, but see below.*/ unfog=b2d(101) /*there's no bin──►decimal, but see below.*/
do j=0 to 27 /*show some simple low-value conversions. */ say right(j,2) 'in decimal is' d2b(j) "in binary and" d2x(j) 'in hex.' end /*j*/
exit /*stick a fork in it, we're done.*/ /*────────────────────────────add these subroutines to end─of─program. */ d2b: return word(strip(x2b(d2x(arg(1))),'L',0) 0,1) /*convert dec──►bin*/ b2d: return x2d(b2x(arg(1))) /*convert bin──►dec*/ b2c: return x2c(b2x(arg(1))) /*convert bin──►chr*/ c2b: return word(strip(x2b(c2x(arg(1))),'L',0) 0,1) /*convert chr──►bin*/</lang>
Ring
<lang ring> see number("0") + nl see number("123456789") + nl see number("-987654321") + nl </lang> Output:
0 123456789 -987654321
Ruby
The String class has methods to coerce a string into another form: <lang ruby>dec1 = "0123459" hex2 = "abcf123" oct3 = "7651" bin4 = "101011001"
p dec1.to_i # => 123459 p hex2.hex # => 180154659 p oct3.oct # => 4009
- nothing for binary</lang>
The String class has to_i(base) method ( base : 2 .. 36 ). Invalid characters past the end of a valid number are ignored. (This method never raises an exception when base is valid.) <lang ruby>p dec1.to_i(10) # => 123459 p hex2.to_i(16) # => 180154659 p oct3.to_i(8) # => 4009 p bin4.to_i(2) # => 345 p "xyz9".to_i(10) # => 0 If there is not a valid letter, 0 is returned.</lang>
The Integer() method can parse a string, provided the string has the right prefix: <lang ruby>p ((Integer(dec1) rescue nil)) # => ArgumentError: invalid value for Integer: "0123459" p Integer(dec1.sub(/^0+/,"")) # => 123459 p Integer("0d" + dec1) # => 123459 p Integer("0x" + hex2) # => 180154659 p Integer("0" + oct3) # => 4009 p Integer("0o" + oct3) # => 4009 p Integer("0b" + bin4) # => 345</lang>
So can the .to_i(0) method, which never raises an exception:
<lang ruby>p dec1.to_i(0) # => 5349 (which is 12345 in octal, the 9 is discarded)
p ("0d" + dec1).to_i(0) # => 123459
p ("0x" + hex2).to_i(0) # => 180154659
p ("0" + oct3).to_i(0) # => 4009
p ("0o" + oct3).to_i(0) # => 4009
p ("0b" + bin4).to_i(0) # => 345</lang>
And then there's the poorly documented Scanf module in the Ruby stdlib, that seems to wrap the matched value in an array: <lang ruby>require 'scanf' p dec1.scanf("%d") # => [123459] p hex2.scanf("%x") # => [180154659] p oct3.scanf("%o") # => [4009]
- no scanf specifier for binary numbers.</lang>
Scheme
<lang scheme>> (string->number "abcf123" 16) ; hex 180154659 > (string->number "123459" 10) ; decimal, the "10" is optional 123459 > (string->number "7651" 8) ; octal 4009 > (string->number "101011001" 2) ; binary 345</lang>
Seed7
The function integer(str, radix) converts a numeric string, with a specified radix, to an integer.
<lang seed7>$ include "seed7_05.s7i";
const proc: main is func
begin
writeln(integer("0123459", 10));
writeln(integer("abcf123", 16));
writeln(integer("7651", 8));
writeln(integer("1010011010", 2));
writeln(integer("tplig0", 32));
writeln(integer("gc0uy9", 36));
end func;</lang>
- Output:
123459 180154659 4009 666 1000000000 987654321
Sidef
<lang ruby>var dec = '0123459'; var hex_noprefix = 'abcf123'; var hex_withprefix = '0xabcf123'; var oct_noprefix = '7651'; var oct_withprefix = '07651'; var bin_noprefix = '101011001'; var bin_withprefix = '0b101011001';
say dec.num; # => 123459 say hex_noprefix.hex; # => 180154659 say hex_withprefix.hex; # => 180154659 say oct_noprefix.oct; # => 4009 say oct_withprefix.oct; # => 4009 say bin_noprefix.bin; # => 345 say bin_withprefix.bin; # => 345</lang>
Standard ML
<lang sml>- Int.fromString "0123459"; val it = SOME 123459 : int option - StringCvt.scanString (Int.scan StringCvt.HEX) "0xabcf123"; val it = SOME 180154659 : int option - StringCvt.scanString (Int.scan StringCvt.HEX) "abcf123"; val it = SOME 180154659 : int option - StringCvt.scanString (Int.scan StringCvt.OCT) "7651"; val it = SOME 4009 : int option - StringCvt.scanString (Int.scan StringCvt.BIN) "101011001"; val it = SOME 345 : int option</lang>
Tcl
<lang tcl>package require Tcl 8.6; # For easy scanning of binary
- The strings to parse
set dec1 "0123459" set hex2 "abcf123" set oct3 "7651" set bin4 "101011001"
- Parse the numbers
scan $dec1 "%d" v1 scan $hex2 "%x" v2 scan $oct3 "%o" v3 scan $bin4 "%b" v4; # Only 8.6-specific operation; others work in all versions
- Print out what happened
puts "$dec1->$v1 $hex2->$v2 $oct3->$v3 $bin4->$v4"</lang> This produces this output:
0123459->123459 abcf123->180154659 7651->4009 101011001->345
For a general parser up to base 36, a little function can be written: <lang Tcl>proc scanbase {str base} {
set res 0
set digits {0 1 2 3 4 5 6 7 8 9 a b c d e f g h i j k l m n o p q r s t u v w x y z}
foreach char [split [string tolower $str] ""] {
set value [lsearch [lrange $digits 0 [expr {$base - 1}]] $char]
if {$value < 0} {error "bad digit $char"}
set res [expr {$res*$base + $value}]
}
return $res
}</lang> Example:
% scanbase 255 19 822 % scanbase $dec1 8 bad digit 9
XPL0
<lang XPL0>include c:\cxpl\codes; int N; real R; [Text(8, "123_456"); N:= IntIn(8); IntOut(0, N); CrLf(0); Text(8, "ABcd12"); N:= HexIn(8); HexOut(0, N); CrLf(0); Text(8, "-3.14159e3"); R:= RlIn(8); RlOut(0, R); CrLf(0); ]</lang>
- Output:
123456 00ABCD12 -3141.59000
zkl
The compiler knows numbers like 0x123, 0b1|101, 0d1_000 but the number conversion functions don't. <lang zkl>fcn b2b(base){
ns:=[20..30].pump(List,T("toString",base));
ns.println();
ns.pump(List,T("toInt",base)).println("\n")
} b2b(2); b2b(10); b2b(16); b2b(19);</lang> Print 20 .. 30 in binary, decimal, hex & base 19 (or any base 2 .. 32) and parse them to decimal:
- Output:
L("10100","10101","10110","10111","11000","11001","11010","11011","11100","11101","11110")
L(20,21,22,23,24,25,26,27,28,29,30)
L("20","21","22","23","24","25","26","27","28","29","30")
L(20,21,22,23,24,25,26,27,28,29,30)
L("14","15","16","17","18","19","1a","1b","1c","1d","1e")
L(20,21,22,23,24,25,26,27,28,29,30)
L("11","12","13","14","15","16","17","18","19","1a","1b")
L(20,21,22,23,24,25,26,27,28,29,30)
- Programming Tasks
- Arithmetic operations
- Ada
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- C
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