Averages/Mean time of day: Difference between revisions
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{{task|Date and time}}
;Task
A particular activity of bats occurs at these times of the day:
:<
Using the idea that there are twenty-four hours in a day,
which is analogous to there being 360 degrees in a circle,
map times of day to and from angles;
and using the ideas of [[Averages/Mean angle]]
compute and show the average time of the nocturnal activity
to an accuracy of one second of time.
{{task heading|See also}}
{{Related tasks/Statistical measures}}
<hr>
=={{header|11l}}==
{{trans|Python}}
<syntaxhighlight lang="11l">F mean_angle(angles)
V x = sum(angles.map(a -> cos(radians(a)))) / angles.len
V y = sum(angles.map(a -> sin(radians(a)))) / angles.len
R degrees(atan2(y, x))
F mean_time(times)
V t = (times.map(time -> time.split(‘:’)))
V seconds = (t.map(hms -> (Float(hms[2]) + Int(hms[1]) * 60 + Int(hms[0]) * 3600)))
V day = 24 * 60 * 60
V to_angles = seconds.map(s -> s * 360.0 / @day)
V mean_as_angle = mean_angle(to_angles)
V mean_seconds = round(mean_as_angle * day / 360.0)
I mean_seconds < 0
mean_seconds += day
V h = mean_seconds I/ 3600
V m = mean_seconds % 3600
V s = m % 60
m = m I/ 60
R ‘#02:#02:#02’.format(h, m, s)
print(mean_time([‘23:00:17’, ‘23:40:20’, ‘00:12:45’, ‘00:17:19’]))</syntaxhighlight>
{{out}}
<pre>23:47:43</pre>
=={{header|Action!}}==
Action! does not support trigonometry, therefore a simple arithmetic solution has been proposed.
{{libheader|Action! Tool Kit}}
{{libheader|Action! Real Math}}
<syntaxhighlight lang="action!">INCLUDE "H6:REALMATH.ACT"
DEFINE PTR="CARD"
TYPE Time=[BYTE s,m,h]
REAL r60
PROC PrintB2(BYTE b)
IF b<10 THEN Put('0) FI
PrintB(b)
RETURN
PROC PrintTime(Time POINTER t)
PrintB2(t.h) Put(':)
PrintB2(t.m) Put(':)
PrintB2(t.s)
RETURN
PROC Decode(CHAR ARRAY st Time POINTER t)
CHAR ARRAY tmp
IF st(0)#8 THEN Break() FI
SCopyS(tmp,st,1,2) t.h=ValB(tmp)
SCopyS(tmp,st,4,5) t.m=ValB(tmp)
SCopyS(tmp,st,7,8) t.s=ValB(tmp)
RETURN
PROC TimeToSeconds(Time POINTER t REAL POINTER seconds)
REAL r
IntToReal(t.h,seconds)
RealMult(seconds,r60,seconds)
IntToReal(t.m,r)
RealAdd(seconds,r,seconds)
RealMult(seconds,r60,seconds)
IntToReal(t.s,r)
RealAdd(seconds,r,seconds)
RETURN
PROC SecondsToTime(REAL POINTER seconds Time POINTER t)
REAL tmp1,tmp2
RealAssign(seconds,tmp1)
RealMod(tmp1,r60,tmp2)
t.s=RealToInt(tmp2)
RealDivInt(tmp1,r60,tmp2)
RealMod(tmp2,r60,tmp1)
t.m=RealToInt(tmp1)
RealDivInt(tmp2,r60,tmp1)
t.h=RealToInt(tmp1)
RETURN
PROC AverageTime(PTR ARRAY times BYTE count Time POINTER res)
BYTE i
Time t
REAL avg,rcount,seconds,halfDay,day
IntToReal(0,avg)
IntToReal(count,rcount)
ValR("43200",halfDay) ;seconds in the half of day
ValR("86400",day) ;seconds in the whole day
FOR i=0 TO count-1
DO
Decode(times(i),t)
TimeToSeconds(t,seconds)
IF RealLess(seconds,halfDay) THEN
RealAdd(seconds,day,seconds) ;correction of time
FI
RealAdd(avg,seconds,avg)
OD
RealDivInt(avg,rcount,avg)
WHILE RealGreaterOrEqual(avg,day)
DO
RealSub(avg,day,avg) ;correction of time
OD
SecondsToTime(avg,res)
RETURN
PROC Main()
DEFINE COUNT="4"
PTR ARRAY times(COUNT)
Time t
Put(125) PutE() ;clear the screen
IntToReal(60,r60)
times(0)="23:00:17" times(1)="23:40:20"
times(2)="00:12:45" times(3)="00:17:19"
AverageTime(times,COUNT,t)
Print("Mean time is ") PrintTime(t)
RETURN</syntaxhighlight>
{{out}}
[https://gitlab.com/amarok8bit/action-rosetta-code/-/raw/master/images/Mean_time_of_day.png Screenshot from Atari 8-bit computer]
<pre>
Mean time is 23:47:40
</pre>
=={{header|Ada}}==
<syntaxhighlight lang="ada">with Ada.Calendar.Formatting;
with Ada.Command_Line;
with Ada.Numerics.Elementary_Functions;
with Ada.Strings.Fixed;
with Ada.Text_IO;
procedure Mean_Time_Of_Day is
subtype Time is Ada.Calendar.Time;
subtype Time_Of_Day is Ada.Calendar.Day_Duration;
subtype Time_String is String (1 .. 8); -- "HH:MM:SS"
type Time_List is array (Positive range <>) of Time_String;
function Average_Time (List : Time_List) return Time_String is
function To_Time (Time_Image : Time_String) return Time
is (Ada.Calendar.Formatting.Value ("2000-01-01 " & Time_Image));
function To_Time_Of_Day (TS : Time) return Time_Of_Day is
use Ada.Calendar.Formatting;
Hour_Part : constant Time_Of_Day := 60.0 * 60.0 * Hour (TS);
Min_Part : constant Time_Of_Day := 60.0 * Minute (TS);
Sec_Part : constant Time_Of_Day := Time_Of_Day (Second (TS));
begin
return Hour_Part + Min_Part + Sec_Part;
end To_Time_Of_Day;
function To_Time_Image (Angle : Time_Of_Day) return Time_String
is
use Ada.Calendar.Formatting;
TOD : constant Time := Time_Of
(Year => 2000, Month => 1, Day => 1, -- Not used
Seconds => Angle);
begin
return Ada.Strings.Fixed.Tail (Image (TOD), Time_String'Length);
end To_Time_Image;
function Average_Time_Of_Day (List : Time_List) return Time_Of_Day is
use Ada.Numerics.Elementary_Functions;
Cycle : constant Float := Float (Time_Of_Day'Last);
X_Sum, Y_Sum : Float := 0.0;
Angle : Float;
begin
for Time_Stamp of List loop
Angle := Float (To_Time_Of_Day (To_Time (Time_Stamp)));
X_Sum := X_Sum + Cos (Angle, Cycle => Cycle);
Y_Sum := Y_Sum + Sin (Angle, Cycle => Cycle);
end loop;
Angle := Arctan (Y_Sum, X_Sum, Cycle => Cycle);
if Angle < 0.0 then
Angle := Angle + Cycle;
elsif Angle > Cycle then
Angle := Angle - Cycle;
end if;
return Time_Of_Day (Angle);
end Average_Time_Of_Day;
begin
return To_Time_Image (Average_Time_Of_Day (List));
end Average_Time;
use Ada.Command_Line;
List : Time_List (1 .. Argument_Count);
begin
if Argument_Count = 0 then
raise Constraint_Error;
end if;
for A in 1 .. Argument_Count loop
List (A) := Argument (A);
end loop;
Ada.Text_IO.Put_Line (Average_Time (List));
exception
when others =>
Ada.Text_IO.Put_Line ("Usage: mean_time_of_day <time-1> ...");
Ada.Text_IO.Put_Line (" <time-1> ... 'HH:MM:SS' format");
end Mean_Time_Of_Day;</syntaxhighlight>
{{out}}
<pre>
% ./mean_time_of_day 23:00:17 23:40:20 00:12:45 00:17:19
23:47:43
</pre>
=={{header|ALGOL 68}}==
Uses code from the Averages/Mean angle task, included here for convenience.
<syntaxhighlight lang="algol68">
BEGIN # Mean time of day mapping time to angles #
# code from the Averages/Mean angle task - angles are in degrees #
PROC mean angle = ([]REAL angles)REAL:
(
INT size = UPB angles - LWB angles + 1;
REAL y part := 0, x part := 0;
FOR i FROM LWB angles TO UPB angles DO
x part +:= cos (angles[i] * pi / 180);
y part +:= sin (angles[i] * pi / 180)
OD;
arc tan2 (y part / size, x part / size) * 180 / pi
);
# end code from the Averages/Mean angle task #
MODE TIME = STRUCT( INT hh, mm, ss );
OP TOANGLE = ( TIME t )REAL: ( ( ( ( ( ss OF t / 60 ) + mm OF t ) / 60 ) + hh OF t ) * 360 ) / 24;
OP TOTIME = ( REAL a )TIME:
BEGIN
REAL t := ( a * 24 ) / 360;
WHILE t < 0 DO t +:= 24 OD;
WHILE t > 24 DO t -:= 24 OD;
INT hh = ENTIER t;
t -:= hh *:= 60;
INT mm = ENTIER t;
INT ss = ENTIER ( ( t - mm ) * 60 );
( hh, mm, ss )
END # TOTIME # ;
PROC mean time = ( []TIME times )TIME:
BEGIN
[ LWB times : UPB times ]REAL angles;
FOR i FROM LWB times TO UPB times DO angles[ i ] := TOANGLE times[ i ] OD;
TOTIME mean angle( angles )
END # mean time # ;
OP SHOW = ( TIME t )VOID:
BEGIN
PROC d2 = ( INT n )STRING: IF n < 10 THEN "0" ELSE "" FI + whole( n, 0 );
print( ( d2( hh OF t ), ":", d2( mm OF t ), ":", d2( ss OF t ) ) )
END # show time # ;
SHOW mean time( ( ( 23,00,17 ), ( 23,40,20 ), ( 00,12,45 ), ( 00,17,19 ) ) )
END
</syntaxhighlight>
{{out}}
<pre>
23:47:43
</pre>
=={{header|AutoHotkey}}==
{{works with|AutoHotkey 1.1}}
<syntaxhighlight lang="autohotkey">MsgBox, % "The mean time is: " MeanTime(["23:00:17", "23:40:20", "00:12:45", "00:17:19"])
MeanTime(t, x=0, y=0) {
static c := ATan(1) / 45
for k, v in t {
n := StrSplit(v, ":")
r := c * (n[1] * 3600 + n[2] * 60 + n[3]) / 240
x += Cos(r)
y += Sin(r)
}
r := atan2(x, y) / c
r := (r < 0 ? r + 360 : r) / 15
h := SubStr("00" Round(r // 1, 0), -1)
s := SubStr("00" Round(Mod(m := Mod(r, 1) * 60, 1) * 60, 0), -1)
m := SubStr("00" Round(m // 1, 0), -1)
return, h ":" m ":" s
}
atan2(x, y) {
return dllcall("msvcrt\atan2", "Double",y, "Double",x, "CDECL Double")
}</syntaxhighlight>
{{out}}
<pre>The mean time is: 23:47:43</pre>
=={{header|AWK}}==
<syntaxhighlight lang="awk">#!/usr/bin/awk -f
{
c = atan2(0,-1)/(12*60*60);
x=0.0; y=0.0;
for (i=1; i<=NF; i++) {
split($i,a,":");
p = (a[1]*3600+a[2]*60+a[3])*c;
x += sin(p);
y += cos(p);
}
p = atan2(x,y)/c;
if (p<0) p += 24*60*60;
print strftime("%T",p,1);
}</syntaxhighlight>
<pre>$ echo 23:00:17, 23:40:20, 00:12:45, 00:17:19 | awk -f mean_time_of_day.awk
23:47:43</pre>
=={{header|BBC BASIC}}==
{{works with|BBC BASIC for Windows}}
<syntaxhighlight lang="bbcbasic"> nTimes% = 4
DATA 23:00:17, 23:40:20, 00:12:45, 00:17:19
DIM angles(nTimes%-1)
FOR N% = 0 TO nTimes%-1
READ tim$
angles(N%) = FNtimetoangle(tim$)
NEXT
PRINT "Mean time is " FNangletotime(FNmeanangle(angles(), nTimes%))
END
DEF FNtimetoangle(t$)
LOCAL A%, I%
REPEAT
A% = A% * 60 + VAL(t$)
I% = INSTR(t$, ":")
t$ = MID$(t$, I%+1)
UNTIL I% = 0
= A% / 240 - 180
DEF FNangletotime(a)
LOCAL A%, I%, t$
A% = INT((a + 180) * 240 + 0.5)
FOR I% = 1 TO 3
t$ = RIGHT$("0" + STR$(A% MOD 60), 2) + ":" + t$
A% DIV= 60
NEXT
= LEFT$(t$)
DEF FNmeanangle(angles(), N%)
LOCAL I%, addsin, addcos
FOR I% = 0 TO N%-1
addsin += SINRADangles(I%)
addcos += COSRADangles(I%)
NEXT
= DEGFNatan2(addsin, addcos)
DEF FNatan2(y,x) : ON ERROR LOCAL = SGN(y)*PI/2
IF x>0 THEN = ATN(y/x) ELSE IF y>0 THEN = ATN(y/x)+PI ELSE = ATN(y/x)-PI</syntaxhighlight>
{{out}}
<pre>
Mean time is 23:47:43
</pre>
=={{header|C}}==
<syntaxhighlight lang="c">#include<stdlib.h>
#include<math.h>
#include<stdio.h>
Line 81 ⟶ 445:
meanTime.second);
return 0;
}</syntaxhighlight>
{{out}}
<pre>
Enter number of inputs : 4
Line 92 ⟶ 453:
Enter the data separated by a space between each unit : 23:00:17 23:40:20 00:12:45 00:17:19
The mean time is : 23:47:43</pre>
----
=={{header|C sharp|C#}}==
<syntaxhighlight lang="csharp">using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using static System.Math;
namespace RosettaCode;
class Program
{
private const int SecondsPerDay = 60 * 60 * 24;
static void Main()
{
var digitimes = new List<TimeSpan>();
Console.WriteLine("Enter times, end with no input: ");
while (true) {
string input = Console.ReadLine();
if (string.IsNullOrWhiteSpace(input)) break;
if (TimeSpan.TryParse(input, out var digitime)) {
digitimes.Add(digitime);
} else {
Console.WriteLine("Seems this is wrong input: ignoring time");
}
}
if(digitimes.Count() > 0)
Console.WriteLine($"The mean time is : {MeanTime(digitimes)}");
}
public static TimeSpan MeanTime(IEnumerable<TimeSpan> ts) => FromDegrees(MeanAngle(ts.Select(ToDegrees)));
public static double ToDegrees(TimeSpan ts) => ts.TotalSeconds * 360d / SecondsPerDay;
public static TimeSpan FromDegrees(double degrees) => TimeSpan.FromSeconds((int)(degrees * SecondsPerDay / 360));
public static double MeanAngle(IEnumerable<double> angles)
{
var x = angles.Average(a => Cos(a * PI / 180));
var y = angles.Average(a => Sin(a * PI / 180));
return (Atan2(y, x) * 180 / PI + 360) % 360;
}
}
</syntaxhighlight>
{{out}}
<pre>
Enter times, end with no input:
23:00:17
23:40:20
00:12:45
00:17:19
The mean time is : 23:47:43
</pre>
=={{header|C++}}==
<syntaxhighlight lang="cpp">#include <iomanip>
#include <iostream>
#include <vector>
#define _USE_MATH_DEFINES
#include <math.h>
struct Time {
int hour, minute, second;
friend std::ostream &operator<<(std::ostream &, const Time &);
};
std::ostream &operator<<(std::ostream &os, const Time &t) {
return os << std::setfill('0')
<< std::setw(2) << t.hour << ':'
<< std::setw(2) << t.minute << ':'
<< std::setw(2) << t.second;
}
double timeToDegrees(Time &&t) {
return 360.0 * t.hour / 24.0
+ 360.0 * t.minute / (24 * 60.0)
+ 360.0 * t.second / (24 * 3600.0);
}
Time degreesToTime(double angle) {
while (angle < 0.0) {
angle += 360.0;
}
while (angle > 360.0) {
angle -= 360.0;
}
double totalSeconds = 24.0 * 60 * 60 * angle / 360;
Time t;
t.second = (int)totalSeconds % 60;
t.minute = ((int)totalSeconds % 3600 - t.second) / 60;
t.hour = (int)totalSeconds / 3600;
return t;
}
double meanAngle(const std::vector<double> &angles) {
double yPart = 0.0, xPart = 0.0;
for (auto a : angles) {
xPart += cos(a * M_PI / 180);
yPart += sin(a * M_PI / 180);
}
return atan2(yPart / angles.size(), xPart / angles.size()) * 180 / M_PI;
}
int main() {
std::vector<double> tv;
tv.push_back(timeToDegrees({ 23, 0, 17 }));
tv.push_back(timeToDegrees({ 23, 40, 20 }));
tv.push_back(timeToDegrees({ 0, 12, 45 }));
tv.push_back(timeToDegrees({ 0, 17, 19 }));
double ma = meanAngle(tv);
auto mt = degreesToTime(ma);
std::cout << mt << '\n';
return 0;
}</syntaxhighlight>
{{out}}
<pre>23:47:43</pre>
=={{header|Common Lisp}}==
{{trans|Echo Lisp}}
<syntaxhighlight lang="lisp">;; * Loading the split-sequence library
(eval-when (:compile-toplevel :load-toplevel :execute)
(ql:quickload '("split-sequence")))
;; * The package definition
(defpackage :mean-time-of-day
(:use :common-lisp :iterate :split-sequence))
(in-package :mean-time-of-day)
;; * The data
(defparameter *time-values*
'("23:00:17" "23:40:20" "00:12:45" "00:17:19"))
(defun time->radian (time)
"Returns the radian value for TIME given as a STRING like HH:MM:SS. Assuming a
valid input value."
(destructuring-bind (h m s)
(mapcar #'parse-integer (split-sequence #\: time))
(+ (* h (/ PI 12)) (* m (/ PI 12 60)) (* s (/ PI 12 3600)))))
(defun radian->time (radian)
"Returns the corresponding time as a string like HH:MM:SS for RADIAN."
(let* ((time (if (plusp radian)
(round (/ (* 12 3600 radian) PI))
(round (/ (* 12 3600 (+ radian (* 2 PI))) PI))))
(h (floor time 3600))
(m (floor (- time (* h 3600)) 60))
(s (- time (* h 3600) (* m 60))))
(format nil "~2,'0D:~2,'0D:~2,'0D" h m s)))
(defun make-polar (rho theta)
"Returns a complex representing the polar coordinates."
(complex (* rho (cos theta)) (* rho (sin theta))))
(defun mean-time (times)
"Returns the mean time value within 24h of the list of TIMES given as strings
HH:MM:SS."
(radian->time (phase
(reduce #'+ (mapcar (lambda (time)
(make-polar 1 (time->radian time))) times)))))
</syntaxhighlight>
{{out}}
<pre>MEAN-TIME-OF-DAY> (mean-time *time-values*)
"23:47:43"</pre>
=={{header|D}}==
{{trans|Python}}
<syntaxhighlight lang="d">import std.stdio, std.range, std.algorithm, std.complex, std.math,
std.format, std.conv;
double radians(in double d) pure nothrow @safe @nogc {
return d * PI / 180;
}
double degrees(in double r) pure nothrow @safe @nogc {
return r * 180 / PI;
}
double meanAngle(in double[] deg) pure nothrow @safe @nogc {
return (deg.map!(d => fromPolar(1, d.radians)).sum / deg.length).arg.degrees;
}
string meanTime(in string[] times) pure @safe {
auto t = times.map!(times => times.split(':').to!(int[3]));
assert(t.all!(hms => 24.iota.canFind(hms[0]) &&
60.iota.canFind(hms[1]) &&
60.iota.canFind(hms[2])),
"Invalid time");
auto seconds = t.map!(hms => hms[2] + hms[1] * 60 + hms[0] * 3600);
enum day = 24 * 60 * 60;
const to_angles = seconds.map!(s => s * 360.0 / day).array;
immutable mean_as_angle = to_angles.meanAngle;
auto mean_seconds_fp = mean_as_angle * day / 360.0;
if (mean_seconds_fp < 0)
mean_seconds_fp += day;
immutable mean_seconds = mean_seconds_fp.to!uint;
immutable h = mean_seconds / 3600;
immutable m = mean_seconds % 3600;
return "%02d:%02d:%02d".format(h, m / 60, m % 60);
}
void main() @safe {
["23:00:17", "23:40:20", "00:12:45", "00:17:19"].meanTime.writeln;
}</syntaxhighlight>
{{out}}
<pre>23:47:43</pre>
=={{header|Delphi}}==
{{libheader| System.SysUtils}}
{{libheader| System.Math}}
{{Trans|Go}}
<syntaxhighlight lang="delphi">
program Averages_Mean_time_of_day;
{$APPTYPE CONSOLE}
uses
System.SysUtils,
System.Math;
const
Inputs: TArray<string> = ['23:00:17', '23:40:20', '00:12:45', '00:17:19'];
function ToTimes(ts: TArray<string>): TArray<TTime>;
begin
SetLength(result, length(ts));
for var i := 0 to High(ts) do
Result[i] := StrToTime(ts[i]);
end;
function MeanTime(times: TArray<TTime>): TTime;
var
ssum, csum: TTime;
h, m, s, ms: word;
dayFrac, fsec, ssin, ccos: double;
begin
if Length(times) = 0 then
exit(0);
ssum := 0;
csum := 0;
for var t in times do
begin
DecodeTime(t, h, m, s, ms);
fsec := (h * 60 + m) * 60 + s + ms / 1000;
ssin := sin(fsec * Pi / (12 * 60 * 60));
ccos := cos(fsec * Pi / (12 * 60 * 60));
ssum := ssum + ssin;
csum := csum + ccos;
end;
if (ssum = 0) and (csum = 0) then
raise Exception.Create('Error MeanTime: Mean undefined');
dayFrac := frac(1 + ArcTan2(ssum, csum) / (2 * Pi));
fsec := dayFrac * 24 * 3600;
ms := Trunc(frac(fsec) * 1000);
s := trunc(fsec) mod 60;
m := trunc(fsec) div 60 mod 60;
h := trunc(fsec) div 3600;
Result := EncodeTime(h, m, s, ms);
end;
begin
writeln(TimeToStr(MeanTime(ToTimes(Inputs))));
readln;
end.</syntaxhighlight>
=={{header|EasyLang}}==
{{trans|C}}
<syntaxhighlight lang=easylang>
func tm2deg t$ .
t[] = number strsplit t$ ":"
return 360 * t[1] / 24.0 + 360 * t[2] / (24 * 60.0) + 360 * t[3] / (24 * 3600.0)
.
func$ deg2tm deg .
len t[] 3
h = floor (24 * 60 * 60 * deg / 360)
t[3] = h mod 60
h = h div 60
t[2] = h mod 60
t[1] = h div 60
for h in t[]
if h < 10
s$ &= 0
.
s$ &= h
s$ &= ":"
.
return substr s$ 1 8
.
func mean ang[] .
for ang in ang[]
x += cos ang
y += sin ang
.
return atan2 (y / len ang[]) (x / len ang[])
.
in$ = "23:00:17 23:40:20 00:12:45 00:17:19"
for s$ in strsplit in$ " "
ar[] &= tm2deg s$
.
print deg2tm (360 + mean ar[])
</syntaxhighlight>
=={{header|EchoLisp}}==
<syntaxhighlight lang="scheme">
;; string hh:mm:ss to radians
(define (time->radian time)
(define-values (h m s) (map string->number (string-split time ":")))
(+ (* h (/ PI 12)) (* m (/ PI 12 60)) (* s (/ PI 12 3600))))
;; radians to string hh:mm;ss
(define (radian->time rad)
(when (< rad 0) (+= rad (* 2 PI)))
(define t (round (/ (* 12 3600 rad) PI)))
(define h (quotient t 3600))
(define m (quotient (- t (* h 3600)) 60))
(define s (- t (* 3600 h) (* 60 m)))
(string-join (map number->string (list h m s)) ":"))
(define (mean-time times)
(radian->time
(angle
(for/sum ((t times)) (make-polar 1 (time->radian t))))))
(mean-time '{"23:00:17" "23:40:20" "00:12:45" "00:17:19"})
→ "23:47:43"
</syntaxhighlight>
=={{header|Erlang}}==
<syntaxhighlight lang="erlang">
-module( mean_time_of_day ).
-export( [from_times/1, task/0] ).
from_times( Times ) ->
Seconds = [seconds_from_time(X) || X <- Times],
Degrees = [degrees_from_seconds(X) || X <- Seconds],
Average = mean_angle:from_degrees( Degrees ),
time_from_seconds( seconds_from_degrees(Average) ).
task() ->
Times = ["23:00:17", "23:40:20", "00:12:45", "00:17:19"],
io:fwrite( "The mean time of ~p is: ~p~n", [Times, from_times(Times)] ).
degrees_from_seconds( Seconds ) when Seconds < (24 * 3600) -> (Seconds * 360) / (24 * 3600).
seconds_from_degrees( Degrees ) when Degrees < 0 -> seconds_from_degrees( Degrees + 360 );
seconds_from_degrees( Degrees ) when Degrees < 360 -> (Degrees * 24 * 3600) / 360.
seconds_from_time( Time ) ->
{ok, [Hours, Minutes, Seconds], _Rest} = io_lib:fread( "~d:~d:~d", Time ),
Hours * 3600 + Minutes * 60 + Seconds.
time_from_seconds( Seconds_float ) ->
Seconds = erlang:round( Seconds_float ),
Hours = Seconds div 3600,
Minutes = (Seconds - (Hours * 3600)) div 60,
Secs = Seconds - (Hours * 3600) - (Minutes * 60),
lists:flatten( io_lib:format("~2.10.0B:~2.10.0B:~2.10.0B", [Hours, Minutes, Secs]) ).
</syntaxhighlight>
{{out}}
<pre>
17> mean_time_of_day:task().
The mean time of ["23:00:17","23:40:20","00:12:45","00:17:19"] is: "23:47:43"
</pre>
=={{header|Euphoria}}==
{{works with|OpenEuphoria}}
<syntaxhighlight lang="euphoria">
include std/console.e
include std/math.e
include std/mathcons.e
include std/sequence.e
include std/get.e
function T2D(sequence TimeSeq)
return (360 * TimeSeq[1] / 24 + 360 * TimeSeq[2] / (24 * 60) +
360 * TimeSeq[3] / (24 * 3600))
end function
function D2T(atom angle)
sequence TimeSeq = {0,0,0}
atom seconds = 24 * 60 * 60 * angle / 360
TimeSeq[3] = mod(seconds,60)
TimeSeq[2] = (mod(seconds,3600) - TimeSeq[3]) / 60
TimeSeq[1] = seconds / 3600
return TimeSeq
end function
function MeanAngle(sequence angles)
atom x = 0, y = 0
integer l = length(angles)
for i = 1 to length(angles) do
x += cos(angles[i] * PI / 180)
y += sin(angles[i] * PI / 180)
end for
return atan2(y / l, x / l) * 180 / PI
end function
sequence TimeEntry, TimeList = {}, TimeSeq
puts(1,"Enter times. Enter with no input to end\n")
while 1 do
TimeEntry = prompt_string("")
if equal(TimeEntry,"") then -- no more entries
for i = 1 to length(TimeList) do
TimeList[i] = split(TimeList[i],":") -- split the times into sequences
for j = 1 to 3 do
TimeList[i][j] = defaulted_value(TimeList[i][j],0) -- convert to numerical values
end for
end for
exit
end if
TimeList = append(TimeList,TimeEntry)
end while
sequence AngleList = repeat({},length(TimeList))
for i = 1 to length(AngleList) do
AngleList[i] = T2D(TimeList[i])
end for
sequence MeanTime = D2T(360+MeanAngle(AngleList))
printf(1,"\nMean Time: %d:%d:%d\n",MeanTime)
if getc(0) then end if
</syntaxhighlight>
{{out}}
<pre>
Enter Times. Enter with no input to end.
23:00:17
23:40:20
00:12:45
00:17:19
Mean Time: 23:47:43
</pre>
=={{header|F_Sharp|F#}}==
<syntaxhighlight lang="fsharp">open System
open System.Numerics
let deg2rad d = d * Math.PI / 180.
let rad2deg r = r * 180. / Math.PI
let makeComplex = fun r -> Complex.FromPolarCoordinates(1., r)
// 1 msec = 10000 ticks
let time2deg = TimeSpan.Parse >> (fun ts -> ts.Ticks) >> (float) >> (*) (10e-9/24.)
let deg2time = (*) (24. * 10e7) >> (int64) >> TimeSpan
[<EntryPoint>]
let main argv =
let msg = "Average time for [" + (String.Join("; ",argv)) + "] is"
argv
|> Seq.map (time2deg >> deg2rad >> makeComplex)
|> Seq.fold (fun x y -> Complex.Add(x,y)) Complex.Zero
|> fun c -> c.Phase |> rad2deg
|> fun d -> if d < 0. then d + 360. else d
|> deg2time |> fun t -> t.ToString(@"hh\:mm\:ss")
|> printfn "%s: %s" msg
0</syntaxhighlight>
{{out}}
<pre>>RosettaCode 23:00:17 23:40:20 00:12:45 00:17:19
Average time for [23:00:17; 23:40:20; 00:12:45; 00:17:19] is: 23:47:43</pre>
=={{header|Factor}}==
<syntaxhighlight lang="factor">USING: arrays formatting kernel math math.combinators
math.functions math.libm math.parser math.trig qw sequences
splitting ;
IN: rosetta-code.mean-time
CONSTANT: input qw{ 23:00:17 23:40:20 00:12:45 00:17:19 }
: time>deg ( hh:mm:ss -- x )
":" split [ string>number ] map first3
[ 15 * ] [ 1/4 * ] [ 1/240 * ] tri* + + ;
: mean-angle ( seq -- x )
[ deg>rad ] map [ [ sin ] map-sum ] [ [ cos ] map-sum ]
[ length ] tri recip [ * ] curry bi@ fatan2 rad>deg ;
: cutf ( x -- str y )
[ >integer number>string ] [ dup floor - ] bi ;
: mean-time ( seq -- str )
[ time>deg ] map mean-angle [ 360 + ] when-negative 24 *
360 / cutf 60 * cutf 60 * round cutf drop 3array ":" join ;
: mean-time-demo ( -- )
input dup mean-time "Mean time for %u is %s.\n" printf ;
MAIN: mean-time-demo</syntaxhighlight>
{{out}}
<pre>
Mean time for { "23:00:17" "23:40:20" "00:12:45" "00:17:19" } is 23:47:43.
</pre>
=={{header|Fortran}}==
{{works with|gfortran 5.1.0}}
<syntaxhighlight lang="fortran">
program mean_time_of_day
implicit none
integer(kind=4), parameter :: dp = kind(0.0d0)
type time_t
integer(kind=4) :: hours, minutes, seconds
end type
character(len=8), dimension(4), parameter :: times = &
(/ '23:00:17', '23:40:20', '00:12:45', '00:17:19' /)
real(kind=dp), dimension(size(times)) :: angles
real(kind=dp) :: mean
angles = time_to_angle(str_to_time(times))
mean = mean_angle(angles)
if (mean < 0) mean = 360 + mean
write(*, fmt='(I2.2, '':'', I2.2, '':'', I2.2)') angle_to_time(mean)
contains
real(kind=dp) function mean_angle(angles)
real(kind=dp), dimension(:), intent (in) :: angles
real(kind=dp) :: x, y
x = sum(sin(radians(angles)))/size(angles)
y = sum(cos(radians(angles)))/size(angles)
mean_angle = degrees(atan2(x, y))
end function
elemental real(kind=dp) function radians(angle)
real(kind=dp), intent (in) :: angle
real(kind=dp), parameter :: pi = 4d0*atan(1d0)
radians = angle/180*pi
end function
elemental real(kind=dp) function degrees(angle)
real(kind=dp), intent (in) :: angle
real(kind=dp), parameter :: pi = 4d0*atan(1d0)
degrees = 180*angle/pi
end function
elemental type(time_t) function str_to_time(str)
character(len=*), intent (in) :: str
! Assuming time in format hh:mm:ss
read(str, fmt='(I2, 1X, I2, 1X, I2)') str_to_time
end function
elemental real(kind=dp) function time_to_angle(time) result (res)
type(time_t), intent (in) :: time
real(kind=dp) :: seconds
real(kind=dp), parameter :: seconds_in_day = 24*60*60
seconds = time%seconds + 60*time%minutes + 60*60*time%hours
res = 360*seconds/seconds_in_day
end function
elemental type(time_t) function angle_to_time(angle)
real(kind=dp), intent (in) :: angle
real(kind=dp) :: seconds
real(kind=dp), parameter :: seconds_in_day = 24*60*60
seconds = seconds_in_day*angle/360d0
angle_to_time%hours = int(seconds/60d0/60d0)
seconds = mod(seconds, 60d0*60d0)
angle_to_time%minutes = int(seconds/60d0)
angle_to_time%seconds = mod(seconds, 60d0)
end function
end program
</syntaxhighlight>
{{out}}
<pre>
23:47:43
</pre>
=={{header|FreeBASIC}}==
<syntaxhighlight lang="freebasic">' FB 1.05.0 Win64
Const pi As Double = 3.1415926535897932
Function meanAngle(angles() As Double) As Double
Dim As Integer length = Ubound(angles) - Lbound(angles) + 1
Dim As Double sinSum = 0.0
Dim As Double cosSum = 0.0
For i As Integer = LBound(angles) To UBound(angles)
sinSum += Sin(angles(i) * pi / 180.0)
cosSum += Cos(angles(i) * pi / 180.0)
Next
Return Atan2(sinSum / length, cosSum / length) * 180.0 / pi
End Function
' time string assumed to be in format "hh:mm:ss"
Function timeToSecs(t As String) As Integer
Dim As Integer hours = Val(Left(t, 2))
Dim As Integer mins = Val(Mid(t, 4, 2))
Dim As Integer secs = Val(Right(t, 2))
Return 3600 * hours + 60 * mins + secs
End Function
' 1 second of time = 360/(24 * 3600) = 1/240th degree
Function timeToDegrees(t As String) As Double
Dim secs As Integer = timeToSecs(t)
Return secs/240.0
End Function
Function degreesToTime(d As Double) As String
If d < 0 Then d += 360.0
Dim secs As Integer = d * 240.0
Dim hours As Integer = secs \ 3600
Dim mins As Integer = secs Mod 3600
secs = mins Mod 60
mins = mins \ 60
Dim hBuffer As String = Right("0" + Str(hours), 2)
Dim mBuffer As String = Right("0" + Str(mins), 2)
Dim sBuffer As String = Right("0" + Str(secs), 2)
Return hBuffer + ":" + mBuffer + ":" + sBuffer
End Function
Dim tm(1 To 4) As String = {"23:00:17", "23:40:20", "00:12:45", "00:17:19"}
Dim angles(1 To 4) As Double
For i As Integer = 1 To 4
angles(i) = timeToDegrees(tm(i))
Next
Dim mean As Double = meanAngle(angles())
Print "Average time is : "; degreesToTime(mean)
Print
Print "Press any key to quit"
Sleep</syntaxhighlight>
{{out}}
<pre>
Average time is : 23:47:43
</pre>
=={{header|Go}}==
<
import (
Line 146 ⟶ 1,160:
_, dayFrac := math.Modf(1 + math.Atan2(ssum, csum)/(2*math.Pi))
return mean.Add(time.Duration(dayFrac * 24 * float64(time.Hour))), nil
}</
{{out}}
<pre>
23:47:43
</pre>
=={{header|Groovy}}==
Solution:
<syntaxhighlight lang="groovy">import static java.lang.Math.*
final format = 'HH:mm:ss', clock = PI / 12, millisPerHr = 3600*1000
final tzOffset = new Date(0).timezoneOffset / 60
def parseTime = { time -> (Date.parse(format, time).time / millisPerHr) - tzOffset }
def formatTime = { time -> new Date((time + tzOffset) * millisPerHr as int).format(format) }
def mean = { list, closure -> list.sum(closure)/list.size() }
def meanTime = { ... timeStrings ->
def times = timeStrings.collect(parseTime)
formatTime(atan2( mean(times) { sin(it * clock) }, mean(times) { cos(it * clock) }) / clock)
}</syntaxhighlight>
Test:
<syntaxhighlight lang="groovy">println (meanTime("23:00:17", "23:40:20", "00:12:45", "00:17:19"))</syntaxhighlight>
{{out}}
<pre>23:47:43</pre>
=={{header|Haskell}}==
<syntaxhighlight lang="haskell">import Data.Complex (cis, phase)
import Data.List.Split (splitOn)
import Text.Printf (printf)
timeToRadians :: String -> Float
timeToRadians time =
let hours:minutes:seconds:_ = splitOn ":" time
s = fromIntegral (read seconds :: Int)
m = fromIntegral (read minutes :: Int)
h = fromIntegral (read hours :: Int)
in (2*pi)*(h+ (m + s/60.0 )/60.0 )/24.0
radiansToTime :: Float -> String
radiansToTime r =
let tau = pi*2
(_,fDay) = properFraction (r / tau) :: (Int, Float)
fDayPositive = if fDay < 0 then 1.0+fDay else fDay
(hours, fHours) = properFraction $ 24.0 * fDayPositive
(minutes, fMinutes) = properFraction $ 60.0 * fHours
seconds = 60.0 * fMinutes
in printf "%0d" (hours::Int) ++ ":" ++ printf "%0d" (minutes::Int) ++ ":" ++ printf "%0.0f" (seconds::Float)
meanAngle :: [Float] -> Float
meanAngle = phase . sum . map cis
main :: IO ()
main = putStrLn $ radiansToTime $ meanAngle $ map timeToRadians ["23:00:17", "23:40:20", "00:12:45", "00:17:19"]
</syntaxhighlight>
{{out}}
<pre>23:47:43</pre>
=={{header|Icon}} and {{header|Unicon}}==
<syntaxhighlight lang="text">procedure main(A)
every put(B := [], ct2a(!A))
write(ca2t(meanAngle(B)))
end
procedure ct2a(t)
t ? {s := ((1(move(2),move(1))*60 + 1(move(2),move(1)))*60 + move(2))}
return (360.0/86400.0) * s
end
procedure ca2t(a)
while a < 0 do a +:= 360.0
t := integer((86400.0/360.0)*a + 0.5)
s := left(1(.t % 60, t /:= 60),2,"0")
s := left(1(.t % 60, t /:= 60),2,"0")||":"||s
s := left(t,2,"0")||":"||s
return s
end
procedure meanAngle(A)
every (sumSines := 0.0) +:= sin(dtor(!A))
every (sumCosines := 0.0) +:= cos(dtor(!A))
return rtod(atan(sumSines/*A,sumCosines/*A))
end</syntaxhighlight>
Sample run:
<pre>
->amtod 23:00:17 23:40:20 00:12:45 00:17:19
23:47:43
->
</pre>
=={{header|J}}==
use <code>avgAngleR</code> from [[Averages/Mean angle#J]]
<
parseTimes=: ([: _&".;._2 ,&':');._2
secsFromTime=: 24 60 60 #. ] NB. convert from time to seconds
rft=: 2r86400p1 * secsFromTime NB. convert from time to radians
meanTime=: 'hh:mm:ss' fmtTime [: secsFromTime [: avgAngleR&.rft parseTimes</
{{out|Example Use}}
<syntaxhighlight lang="j"> meanTime '23:00:17 23:40:20 00:12:45 00:17:19 '
23:47:43</syntaxhighlight>
=={{header|Java}}==
{{trans|Kotlin}}
<syntaxhighlight lang="java">public class MeanTimeOfDay {
static double meanAngle(double[] angles) {
int len = angles.length;
double sinSum = 0.0;
for (int i = 0; i < len; i++) {
sinSum += Math.sin(angles[i] * Math.PI / 180.0);
}
double cosSum = 0.0;
for (int i = 0; i < len; i++) {
cosSum += Math.cos(angles[i] * Math.PI / 180.0);
}
return Math.atan2(sinSum / len, cosSum / len) * 180.0 / Math.PI;
}
/* time string assumed to be in format "hh:mm:ss" */
static int timeToSecs(String t) {
int hours = Integer.parseInt(t.substring(0, 2));
int mins = Integer.parseInt(t.substring(3, 5));
int secs = Integer.parseInt(t.substring(6, 8));
return 3600 * hours + 60 * mins + secs;
}
/* 1 second of time = 360/(24 * 3600) = 1/240th degree */
static double timeToDegrees(String t) {
return timeToSecs(t) / 240.0;
}
static String degreesToTime(double d) {
if (d < 0.0) d += 360.0;
int secs = (int)(d * 240.0);
int hours = secs / 3600;
int mins = secs % 3600;
secs = mins % 60;
mins /= 60;
return String.format("%2d:%2d:%2d", hours, mins, secs);
}
public static void main(String[] args) {
String[] tm = {"23:00:17", "23:40:20", "00:12:45", "00:17:19"};
double[] angles = new double[4];
for (int i = 0; i < 4; i++) angles[i] = timeToDegrees(tm[i]);
double mean = meanAngle(angles);
System.out.println("Average time is : " + degreesToTime(mean));
}
}</syntaxhighlight>
{{out}}
<pre>
Average time is : 23:47:43
</pre>
=={{header|Javascript}}==
{{works with|Node.js}}
<syntaxhighlight lang="javascript">var args = process.argv.slice(2);
function time_to_seconds( hms ) {
var parts = hms.split(':');
var h = parseInt(parts[0]);
var m = parseInt(parts[1]);
var s = parseInt(parts[2]);
if ( h < 12 ) {
h += 24;
}
var seconds = parseInt(parts[0]) * 60 * 60 + parseInt(parts[1]) * 60 + parseInt(parts[2]);
return seconds;
}
function seconds_to_time( s ) {
var h = Math.floor( s/(60 * 60) );
if ( h < 10 ) {
h = '0' + h;
}
s = s % (60 * 60);
var m = Math.floor( s/60 );
if ( m < 10 ) {
m = '0' + m;
}
s = s % 60
if ( s < 10 ) {
s = '0' + s;
}
return h + ':' + m + ':' + s;
}
var sum = 0, count = 0, idx;
for (idx in args) {
var seconds = time_to_seconds( args[idx] );
sum += seconds;
count++;
}
var seconds = Math.floor( sum / count )
console.log( 'Mean time is ', seconds_to_time(seconds));
</syntaxhighlight>
{{out}}
<pre>
$ node mean_time.js 23:00:17 23:40:20 00:12:45 00:17:19
Mean time is 23:47:40</pre>
=={{header|jq}}==
{{works with|jq|1.4}}
The "mean time" of two times that differ by 12 hours (e.g. ["00:00:00", "12:00:00"]) is not very well-defined, and is accordingly computed as null here.
<syntaxhighlight lang="jq"># input: array of "h:m:s"
def mean_time_of_day:
def pi: 4 * (1|atan);
def to_radians: pi * . /(12*60*60);
def from_radians: (. * 12*60*60) / pi;
def secs2time: # produce "hh:mm:ss" string
def pad: tostring | (2 - length) * "0" + .;
"\(./60/60 % 24 | pad):\(./60 % 60 | pad):\(. % 60 | pad)";
def round:
if . < 0 then -1 * ((- .) | round) | if . == -0 then 0 else . end
else floor as $x
| if (. - $x) < 0.5 then $x else $x+1 end
end;
map( split(":")
| map(tonumber)
| (.[0]*3600 + .[1]*60 + .[2])
| to_radians )
| (map(sin) | add) as $y
| (map(cos) | add) as $x
| if $x == 0 then (if $y > 3e-14 then pi/2 elif $y < -3e-14 then -(pi/2) else null end)
else ($y / $x) | atan
end
| if . == null then null
else from_radians
| if (.<0) then . + (24*60*60) else . end
| round
| secs2time
end ;</syntaxhighlight>
'''Examples'''
<syntaxhighlight lang="jq">["0:0:0", "12:0:0" ],
["0:0:0", "24:0:0" ],
["1:0:0", "1:0:0" ],
["20:0:0", "4:0:0" ],
["20:0:0", "4:0:2" ],
["23:0:0", "23:0:0" ],
["23:00:17", "23:40:20", "00:12:45", "00:17:19"]
| mean_time_of_day</syntaxhighlight>
{{out}}
<syntaxhighlight lang="sh">$ jq -r -n -f Mean_time_of_day.jq
null
00:00:00
01:00:00
00:00:00
00:00:01
23:00:00
23:47:43</syntaxhighlight>
=={{header|Julia}}==
{{works with|Julia|0.6}}
{{trans|MATLAB}}
<syntaxhighlight lang="julia">using Statistics
function meantime(times::Array, dlm::String=":")
c = π / (12 * 60 * 60)
a = map(x -> parse.(Int, x), split.(times, dlm))
ϕ = collect(3600t[1] + 60t[2] + t[3] for t in a)
d = angle(mean(exp.(c * im * ϕ))) / 2π # days
if d < 0 d += 1 end
# Convert to h:m:s
h = trunc(Int, d * 24)
m = trunc(Int, d * 24 * 60) - h * 60
s = trunc(Int, d * 24 * 60 * 60) - h * 60 * 60 - m * 60
return "$h:$m:$s"
end
times = String["23:00:17", "23:40:20", "00:12:45", "00:17:19"]
mtime = meantime(times)
println("Times:")
println.(times)
println("Mean: $mtime")</syntaxhighlight>
{{out}}
<pre>Times:
23:00:17
23:40:20
00:12:45
00:17:19
Mean: 23:47:43</pre>
=={{header|Kotlin}}==
{{trans|FreeBASIC}}
<syntaxhighlight lang="scala">// version 1.0.6
fun meanAngle(angles: DoubleArray): Double {
val sinSum = angles.sumByDouble { Math.sin(it * Math.PI / 180.0) }
val cosSum = angles.sumByDouble { Math.cos(it * Math.PI / 180.0) }
return Math.atan2(sinSum / angles.size, cosSum / angles.size) * 180.0 / Math.PI
}
/* time string assumed to be in format "hh:mm:ss" */
fun timeToSecs(t: String): Int {
val hours = t.slice(0..1).toInt()
val mins = t.slice(3..4).toInt()
val secs = t.slice(6..7).toInt()
return 3600 * hours + 60 * mins + secs
}
/* 1 second of time = 360/(24 * 3600) = 1/240th degree */
fun timeToDegrees(t: String): Double = timeToSecs(t) / 240.0
fun degreesToTime(d: Double): String {
var dd = d
if (dd < 0.0) dd += 360.0
var secs = (dd * 240.0).toInt()
val hours = secs / 3600
var mins = secs % 3600
secs = mins % 60
mins /= 60
return String.format("%2d:%2d:%2d", hours, mins, secs)
}
fun main(args: Array<String>) {
val tm = arrayOf("23:00:17", "23:40:20", "00:12:45", "00:17:19")
val angles = DoubleArray(4) { timeToDegrees(tm[it]) }
val mean = meanAngle(angles)
println("Average time is : ${degreesToTime(mean)}")
}</syntaxhighlight>
{{out}}
<pre>
Average time is : 23:47:43
</pre>
=={{header|Liberty BASIC}}==
<syntaxhighlight lang="lb">
global pi
pi = acs(-1)
Print "Average of:"
for i = 1 to 4
read t$
print t$
a=time2angle(t$)
ss=ss+sin(a)
sc=sc+cos(a)
next
a=atan2(ss,sc)
if a<0 then a=a+2*pi
print "is ";angle2time$(a)
end
data "23:00:17", "23:40:20", "00:12:45", "00:17:19"
function nn$(n)
nn$=right$("0";n, 2)
end function
function angle2time$(a)
a=int(a/2/pi*24*60*60)
ss=a mod 60
a=int(a/60)
mm=a mod 60
hh=int(a/60)
angle2time$=nn$(hh);":";nn$(mm);":";nn$(ss)
end function
function time2angle(time$)
hh=val(word$(time$,1,":"))
mm=val(word$(time$,2,":"))
ss=val(word$(time$,3,":"))
time2angle=2*pi*(60*(60*hh+mm)+ss)/24/60/60
end function
function atan2(y, x)
On Error GoTo [DivZero] 'If y is 0 catch division by zero error
atan2 = (2 * (atn((sqr((x * x) + (y * y)) - x)/ y)))
exit function
[DivZero]
atan2 = (y=0)*(x<0)*pi
End Function
</syntaxhighlight>
{{out}}
<pre>
Average of:
23:00:17
23:40:20
00:12:45
00:17:19
is 23:47:43
</pre>
=={{header|Lua}}==
<syntaxhighlight lang="lua">
local times = {"23:00:17","23:40:20","00:12:45","00:17:19"}
-- returns time converted to a radian format
local function timeToAngle(str)
local h,m,s = str:match("(..):(..):(..)")
return (h + m / 60 + s / 3600)/12 * math.pi
end
-- computes the mean of the angles inside a list
local function meanAngle(angles)
local sumSin,sumCos = 0,0
for k,v in pairs(angles) do
sumSin = sumSin + math.sin(v)
sumCos = sumCos + math.cos(v)
end
return math.atan2(sumSin,sumCos)
end
-- converts and angle back to a time string
local function angleToTime(angle)
local abs = angle % (math.pi * 2)
local time = abs / math.pi * 12
local h = math.floor(time)
local m = math.floor(time * 60) % 60
local s = math.floor(time * 3600) % 60
return string.format("%02d:%02d:%02d", h, m, s)
end
-- convert times to angles
for k,v in pairs(times) do
times[k] = timeToAngle(v)
end
print(angleToTime(meanAngle(times)))
</syntaxhighlight>
{{out}}
<pre>
23:47:43
</pre>
=={{header|Mathematica}} / {{header|Wolfram Language}}==
<
StringJoin@
Riffle[ToString /@
Line 172 ⟶ 1,608:
Exp[FromDigits[ToExpression@StringSplit[#, ":"], 60] & /@
list/(24*60*60) 2 Pi I]]]/(2 Pi)], ":"];
meanTime[{"23:00:17", "23:40:20", "00:12:45", "00:17:19"}]</
{{Out}}
<pre>23:47:43</pre>
=={{header|
<syntaxhighlight lang="matlab">function t = mean_time_of_day(t)
c = pi/(12*60*60);
for k=1:length(t)
a = sscanf(t{k},'%d:%d:%d');
phi(k) = (a(1)*3600+a(2)*60+a(3));
end;
d = angle(mean(exp(i*phi*c)))/(2*pi); % days
if (d<0) d += 1;
t = datestr(d,"HH:MM:SS");
end; </syntaxhighlight>
<pre>mean_time_of_day({'23:00:17', '23:40:20', '00:12:45', '00:17:19'})
ans = 23:47:43
</pre>
=={{header|Nim}}==
{{works with|Nim|0.20.0+}}
<syntaxhighlight lang="nim">import math, complex, strutils, sequtils
proc meanAngle(deg: openArray[float]): float =
var c: Complex[float]
for d in deg:
c += rect(1.0, degToRad(d))
radToDeg(phase(c / float(deg.len)))
proc meanTime(times: openArray[string]): string =
const day = 24 * 60 * 60
let
angles = times.map(proc(time: string): float =
let t = time.split(":")
(t[2].parseInt + t[1].parseInt * 60 + t[0].parseInt * 3600) * 360 / day)
ms = (angles.meanAngle * day / 360 + day) mod day
(h,m,s) = (ms.int div 3600, (ms.int mod 3600) div 60, ms.int mod 60)
align($h, 2, '0') & ":" & align($m, 2, '0') & ":" & align($s, 2, '0')
echo meanTime(["23:00:17", "23:40:20", "00:12:45", "00:17:19"])</syntaxhighlight>
{{out}}
<pre>23:47:43</pre>
=={{header|Oberon-2}}==
{{works with|oo2c}}
<syntaxhighlight lang="oberon2">
MODULE AvgTimeOfDay;
IMPORT
M := LRealMath,
T := NPCT:Tools,
Out := NPCT:Console;
CONST
secsDay = 86400;
secsHour = 3600;
secsMin = 60;
toRads = M.pi / 180;
VAR
h,m,s: LONGINT;
data: ARRAY 4 OF LONGREAL;
PROCEDURE TimeToDeg(time: STRING): LONGREAL;
VAR
parts: ARRAY 3 OF STRING;
h,m,s: LONGREAL;
BEGIN
T.Split(time,':',parts);
h := T.StrToInt(parts[0]);
m := T.StrToInt(parts[1]);
s := T.StrToInt(parts[2]);
RETURN (h * secsHour + m * secsMin + s) * 360 / secsDay;
END TimeToDeg;
PROCEDURE DegToTime(d: LONGREAL; VAR h,m,s: LONGINT);
VAR
ds: LONGREAL;
PROCEDURE Mod(x,y: LONGREAL): LONGREAL;
VAR
c: LONGREAL;
BEGIN
c := ENTIER(x / y);
RETURN x - c * y
END Mod;
BEGIN
ds := Mod(d,360.0) * secsDay / 360.0;
h := ENTIER(ds / secsHour);
m := ENTIER(Mod(ds,secsHour) / secsMin);
s := ENTIER(Mod(ds,secsMin));
END DegToTime;
PROCEDURE Mean(g: ARRAY OF LONGREAL): LONGREAL;
VAR
i,l: LONGINT;
sumSin, sumCos: LONGREAL;
BEGIN
i := 0;l := LEN(g);sumSin := 0.0;sumCos := 0.0;
WHILE i < l DO
sumSin := sumSin + M.sin(g[i] * toRads);
sumCos := sumCos + M.cos(g[i] * toRads);
INC(i)
END;
RETURN M.arctan2(sumSin / l,sumCos / l) * 180 / M.pi;
END Mean;
BEGIN
data[0] := TimeToDeg("23:00:17");
data[1] := TimeToDeg("23:40:20");
data[2] := TimeToDeg("00:12:45");
data[3] := TimeToDeg("00:17:19");
DegToTime(Mean(data),h,m,s);
Out.String(":> ");Out.Int(h,0);Out.Char(':');Out.Int(m,0);Out.Char(':');Out.Int(s,0);Out.Ln
END AvgTimeOfDay.
</syntaxhighlight>
{{Out}}
<pre>
:> 23:47:43
</pre>
=={{header|OCaml}}==
<syntaxhighlight lang="ocaml">let pi_twice = 2.0 *. 3.14159_26535_89793_23846_2643
let day = float (24 * 60 * 60)
Line 214 ⟶ 1,768:
Printf.printf "The mean time of [%s] is: %s\n"
(String.concat "; " times)
(string_of_time (mean_time (List.map parse_time times)))</
{{out}}
The mean time of [23:00:17; 23:40:20; 00:12:45; 00:17:19] is: 23:47:43
=={{header|ooRexx}}==
<syntaxhighlight lang="oorexx">/* REXX ---------------------------------------------------------------
* 25.06.2014 Walter Pachl
*--------------------------------------------------------------------*/
times='23:00:17 23:40:20 00:12:45 00:17:19'
sum=0
day=86400
x=0
y=0
Do i=1 To words(times) /* loop over times */
time.i=word(times,i) /* pick a time */
alpha.i=t2a(time.i) /* convert to angle (degrees) */
/* Say time.i format(alpha.i,6,9) */
x=x+rxcalcsin(alpha.i) /* accumulate sines */
y=y+rxcalccos(alpha.i) /* accumulate cosines */
End
ww=rxcalcarctan(x/y) /* compute average angle */
ss=ww*86400/360 /* convert to seconds */
If ss<0 Then ss=ss+day /* avoid negative value */
m=ss%60 /* split into hh mm ss */
s=ss-m*60
h=m%60
m=m-h*60
Say f2(h)':'f2(m)':'f2(s) /* show the mean time */
Exit
t2a: Procedure Expose day /* convert time to angle */
Parse Arg hh ':' mm ':' ss
sec=(hh*60+mm)*60+ss
If sec>(day/2) Then
sec=sec-day
a=360*sec/day
Return a
f2: return right(format(arg(1),2,0),2,0)
::requires rxmath library</syntaxhighlight>
{{out}}
<pre>23:47:43</pre>
=={{header|PARI/GP}}==
<
meanTime(v)=my(x=meanAngle(2*Pi*apply(u->u[1]/24+u[2]/1440+u[3]/86400, v))*12/Pi); [x\1, 60*(x-=x\1)\1, round(60*(60*x-60*x\1))]
meanTime([[23,0,17], [23,40,20], [0,12,45], [0,17,19]])</
{{out}}
<pre>[23, 47, 43
=={{header|Perl
===Traditional===
Using the core module <code>Math::Complex</code> to enable use of complex numbers. The <code>POSIX</code> CPAN module provides the <code>fmod</code> routine for non-integer modulus calculations.
{{trans|Raku}}
<syntaxhighlight lang="perl">use strict;
use warnings;
use POSIX 'fmod';
use Math::Complex;
use List::Util qw(sum);
use utf8;
use constant τ => 2 * 3.1415926535;
# time-of-day to radians
sub tod2rad {
($h,$m,$s) = split /:/, @_[0];
(3600*$h + 60*$m + $s) * τ / 86400;
}
# radians to time-of-day
sub rad2tod {
my $x = $_[0] * 86400 / τ;
sprintf '%02d:%02d:%02d', fm($x/3600,24), fm($x/60,60), fm($x,60);
}
# float modulus, normalized to positive values
sub fm {
my($n,$b) = @_;
$x = fmod($n,$b);
$x += $b if $x < 0;
}
sub phase { arg($_[0]) } # aka theta
sub cis { cos($_[0]) + i*sin($_[0]) }
sub mean_time { rad2tod phase sum map { cis tod2rad $_ } @_ }
@times = ("23:00:17", "23:40:20", "00:12:45", "00:17:19");
print mean_time(@times) . " is the mean time of " . join(' ', @times) . "\n";</syntaxhighlight>
{{out}}
<pre>23:47:43 is the mean time of 23:00:17 23:40:20 00:12:45 00:17:19</pre>
===v5.36===
As previous, but using features from an up-to-date release of Perl, e.g. strict/warn/subroutine signatures without the <code>use</code> boilerplate.
<syntaxhighlight lang="perl">use v5.36;
use POSIX 'fmod';
use Math::Complex;
use List::Util 'sum';
use utf8;
use constant τ => 2 * 2 * atan2(1, 0);
sub R_to_ToD ($radians) { my $x = $radians * 86400 / τ; sprintf '%02d:%02d:%02d', fm($x/3600,24), fm($x/60,60), fm($x,60) }
sub ToD_to_R ($h,$m,$s) { (3600*$h + 60*$m + $s) * τ / 86400 }
sub fm ($n,$b) { my $x = fmod($n,$b); $x += $b if $x < 0 }
sub cis ($radians) { cos($radians) + i*sin($radians) }
sub phase ($Θ) { arg( $Θ ) }
sub mean_time(@t) { R_to_ToD phase sum map { cis ToD_to_R split ':', $_ } @t }
my @times = <23:00:17 23:40:20 00:12:45 00:17:19>;
say my $result = mean_time(@times) . ' is the mean time of ' . join ' ', @times;</syntaxhighlight>
{{out}}
<pre>23:47:43 is the mean time of 23:00:17 23:40:20 00:12:45 00:17:19</pre>
=={{header|Phix}}==
<!--<syntaxhighlight lang="phix">(phixonline)-->
<span style="color: #008080;">with</span> <span style="color: #008080;">javascript_semantics</span>
<span style="color: #008080;">function</span> <span style="color: #000000;">MeanAngle</span><span style="color: #0000FF;">(</span><span style="color: #004080;">sequence</span> <span style="color: #000000;">angles</span><span style="color: #0000FF;">)</span>
<span style="color: #004080;">atom</span> <span style="color: #000000;">x</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">0</span><span style="color: #0000FF;">,</span> <span style="color: #000000;">y</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">0</span>
<span style="color: #008080;">for</span> <span style="color: #000000;">i</span><span style="color: #0000FF;">=</span><span style="color: #000000;">1</span> <span style="color: #008080;">to</span> <span style="color: #7060A8;">length</span><span style="color: #0000FF;">(</span><span style="color: #000000;">angles</span><span style="color: #0000FF;">)</span> <span style="color: #008080;">do</span>
<span style="color: #004080;">atom</span> <span style="color: #000000;">ai_rad</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">angles</span><span style="color: #0000FF;">[</span><span style="color: #000000;">i</span><span style="color: #0000FF;">]*</span><span style="color: #004600;">PI</span><span style="color: #0000FF;">/</span><span style="color: #000000;">180</span>
<span style="color: #000000;">x</span> <span style="color: #0000FF;">+=</span> <span style="color: #7060A8;">cos</span><span style="color: #0000FF;">(</span><span style="color: #000000;">ai_rad</span><span style="color: #0000FF;">)</span>
<span style="color: #000000;">y</span> <span style="color: #0000FF;">+=</span> <span style="color: #7060A8;">sin</span><span style="color: #0000FF;">(</span><span style="color: #000000;">ai_rad</span><span style="color: #0000FF;">)</span>
<span style="color: #008080;">end</span> <span style="color: #008080;">for</span>
<span style="color: #008080;">if</span> <span style="color: #7060A8;">abs</span><span style="color: #0000FF;">(</span><span style="color: #000000;">x</span><span style="color: #0000FF;">)<</span><span style="color: #000000;">1e-16</span> <span style="color: #008080;">then</span> <span style="color: #008080;">return</span> <span style="color: #008000;">"not meaningful"</span> <span style="color: #008080;">end</span> <span style="color: #008080;">if</span>
<span style="color: #008080;">return</span> <span style="color: #7060A8;">atan2</span><span style="color: #0000FF;">(</span><span style="color: #000000;">y</span><span style="color: #0000FF;">,</span><span style="color: #000000;">x</span><span style="color: #0000FF;">)*</span><span style="color: #000000;">180</span><span style="color: #0000FF;">/</span><span style="color: #004600;">PI</span>
<span style="color: #008080;">end</span> <span style="color: #008080;">function</span>
<span style="color: #008080;">function</span> <span style="color: #000000;">toSecAngle</span><span style="color: #0000FF;">(</span><span style="color: #004080;">integer</span> <span style="color: #000000;">hours</span><span style="color: #0000FF;">,</span> <span style="color: #004080;">integer</span> <span style="color: #000000;">minutes</span><span style="color: #0000FF;">,</span> <span style="color: #004080;">integer</span> <span style="color: #000000;">seconds</span><span style="color: #0000FF;">)</span>
<span style="color: #008080;">return</span> <span style="color: #0000FF;">((</span><span style="color: #000000;">hours</span><span style="color: #0000FF;">*</span><span style="color: #000000;">60</span><span style="color: #0000FF;">+</span><span style="color: #000000;">minutes</span><span style="color: #0000FF;">)*</span><span style="color: #000000;">60</span><span style="color: #0000FF;">+</span><span style="color: #000000;">seconds</span><span style="color: #0000FF;">)/(</span><span style="color: #000000;">24</span><span style="color: #0000FF;">*</span><span style="color: #000000;">60</span><span style="color: #0000FF;">*</span><span style="color: #000000;">60</span><span style="color: #0000FF;">)*</span><span style="color: #000000;">360</span>
<span style="color: #008080;">end</span> <span style="color: #008080;">function</span>
<span style="color: #008080;">constant</span> <span style="color: #000000;">Times</span> <span style="color: #0000FF;">=</span> <span style="color: #0000FF;">{</span><span style="color: #000000;">toSecAngle</span><span style="color: #0000FF;">(</span><span style="color: #000000;">23</span><span style="color: #0000FF;">,</span><span style="color: #000000;">00</span><span style="color: #0000FF;">,</span><span style="color: #000000;">17</span><span style="color: #0000FF;">),</span>
<span style="color: #000000;">toSecAngle</span><span style="color: #0000FF;">(</span><span style="color: #000000;">23</span><span style="color: #0000FF;">,</span><span style="color: #000000;">40</span><span style="color: #0000FF;">,</span><span style="color: #000000;">20</span><span style="color: #0000FF;">),</span>
<span style="color: #000000;">toSecAngle</span><span style="color: #0000FF;">(</span><span style="color: #000000;">00</span><span style="color: #0000FF;">,</span><span style="color: #000000;">12</span><span style="color: #0000FF;">,</span><span style="color: #000000;">45</span><span style="color: #0000FF;">),</span>
<span style="color: #000000;">toSecAngle</span><span style="color: #0000FF;">(</span><span style="color: #000000;">00</span><span style="color: #0000FF;">,</span><span style="color: #000000;">17</span><span style="color: #0000FF;">,</span><span style="color: #000000;">19</span><span style="color: #0000FF;">)}</span>
<span style="color: #008080;">function</span> <span style="color: #000000;">toHMS</span><span style="color: #0000FF;">(</span><span style="color: #004080;">object</span> <span style="color: #000000;">s</span><span style="color: #0000FF;">)</span>
<span style="color: #008080;">if</span> <span style="color: #008080;">not</span> <span style="color: #004080;">string</span><span style="color: #0000FF;">(</span><span style="color: #000000;">s</span><span style="color: #0000FF;">)</span> <span style="color: #008080;">then</span>
<span style="color: #008080;">if</span> <span style="color: #000000;">s</span><span style="color: #0000FF;"><</span><span style="color: #000000;">0</span> <span style="color: #008080;">then</span> <span style="color: #000000;">s</span><span style="color: #0000FF;">+=</span><span style="color: #000000;">360</span> <span style="color: #008080;">end</span> <span style="color: #008080;">if</span>
<span style="color: #000000;">s</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">24</span><span style="color: #0000FF;">*</span><span style="color: #000000;">60</span><span style="color: #0000FF;">*</span><span style="color: #000000;">60</span><span style="color: #0000FF;">*</span><span style="color: #000000;">s</span><span style="color: #0000FF;">/</span><span style="color: #000000;">360</span>
<span style="color: #004080;">atom</span> <span style="color: #000000;">hours</span> <span style="color: #0000FF;">=</span> <span style="color: #7060A8;">floor</span><span style="color: #0000FF;">(</span><span style="color: #000000;">s</span><span style="color: #0000FF;">/</span><span style="color: #000000;">3600</span><span style="color: #0000FF;">),</span>
<span style="color: #000000;">mins</span> <span style="color: #0000FF;">=</span> <span style="color: #7060A8;">floor</span><span style="color: #0000FF;">(</span><span style="color: #7060A8;">remainder</span><span style="color: #0000FF;">(</span><span style="color: #000000;">s</span><span style="color: #0000FF;">,</span><span style="color: #000000;">3600</span><span style="color: #0000FF;">)/</span><span style="color: #000000;">60</span><span style="color: #0000FF;">),</span>
<span style="color: #000000;">secs</span> <span style="color: #0000FF;">=</span> <span style="color: #7060A8;">remainder</span><span style="color: #0000FF;">(</span><span style="color: #000000;">s</span><span style="color: #0000FF;">,</span><span style="color: #000000;">60</span><span style="color: #0000FF;">)</span>
<span style="color: #000000;">s</span> <span style="color: #0000FF;">=</span> <span style="color: #7060A8;">sprintf</span><span style="color: #0000FF;">(</span><span style="color: #008000;">"%02d:%02d:%02d"</span><span style="color: #0000FF;">,{</span><span style="color: #000000;">hours</span><span style="color: #0000FF;">,</span><span style="color: #000000;">mins</span><span style="color: #0000FF;">,</span><span style="color: #000000;">secs</span><span style="color: #0000FF;">})</span>
<span style="color: #008080;">end</span> <span style="color: #008080;">if</span>
<span style="color: #008080;">return</span> <span style="color: #000000;">s</span>
<span style="color: #008080;">end</span> <span style="color: #008080;">function</span>
<span style="color: #7060A8;">printf</span><span style="color: #0000FF;">(</span><span style="color: #000000;">1</span><span style="color: #0000FF;">,</span><span style="color: #008000;">"Mean Time is %s\n"</span><span style="color: #0000FF;">,{</span><span style="color: #000000;">toHMS</span><span style="color: #0000FF;">(</span><span style="color: #000000;">MeanAngle</span><span style="color: #0000FF;">(</span><span style="color: #000000;">Times</span><span style="color: #0000FF;">))})</span>
<!--</syntaxhighlight>-->
{{out}}
<pre>
Mean Time is 23:47:43
</pre>
=={{header|PHP}}==
<syntaxhighlight lang="php">
<?php
function time2ang($tim) {
if (!is_string($tim)) return $tim;
$parts = explode(':',$tim);
if (count($parts)!=3) return $tim;
$sec = ($parts[0]*3600)+($parts[1]*60)+$parts[2];
$ang = 360.0 * ($sec/86400.0);
return $ang;
}
function ang2time($ang) {
if (!is_numeric($ang)) return $ang;
$sec = 86400.0 * $ang / 360.0;
$parts = array(floor($sec/3600),floor(($sec % 3600)/60),$sec % 60);
$tim = sprintf('%02d:%02d:%02d',$parts[0],$parts[1],$parts[2]);
return $tim;
}
function meanang($ang) {
if (!is_array($ang)) return $ang;
$sins = 0.0;
$coss = 0.0;
foreach($ang as $a) {
$sins += sin(deg2rad($a));
$coss += cos(deg2rad($a));
}
$avgsin = $sins / (0.0+count($ang));
$avgcos = $coss / (0.0+count($ang));
$avgang = rad2deg(atan2($avgsin,$avgcos));
while ($avgang < 0.0) $avgang += 360.0;
return $avgang;
}
$bats = array('23:00:17','23:40:20','00:12:45','00:17:19');
$angs = array();
foreach ($bats as $t) $angs[] = time2ang($t);
$ma = meanang($angs);
$result = ang2time($ma);
print "The mean time of day is $result (angle $ma).\n";
?>
</syntaxhighlight>
{{out}}
<pre>
The mean time of day is 23:47:43 (angle 356.9306730355).
</pre>
=={{header|PicoLisp}}==
<
(de meanTime (Lst)
Line 253 ⟶ 1,979:
(sum '((S) (cos (*/ ($tim S) pi 43200))) Lst) )
43200 pi )
(tim$ (% (+ Tim 86400) 86400) T) ) )</
{{out|Test
<
-> "23:47:43"</
=={{header|PL/I}}==
<syntaxhighlight lang="pli">*process source attributes xref;
avt: Proc options(main);
/*--------------------------------------------------------------------
* 25.06.2014 Walter Pachl taken from REXX
*-------------------------------------------------------------------*/
Dcl (addr,hbound,sin,cos,atan) Builtin;
Dcl sysprint Print;
Dcl times(4) Char(8) Init('23:00:17','23:40:20','00:12:45','00:17:19');
Dcl time Char(8);
Dcl (alpha,x,y,ss,ww) Dec Float(18) Init(0);
Dcl day Bin Fixed(31) Init(86400);
Dcl pi Dec Float(18) Init(3.14159265358979323846);
Dcl (i,h,m,s) bin Fixed(31) Init(0);
Do i=1 To hbound(times); /* loop over times */
time=times(i); /* pick a time */
alpha=t2a(time); /* convert to angle (radians) */
x=x+sin(alpha); /* accumulate sines */
y=y+cos(alpha); /* accumulate cosines */
End;
ww=atan(x/y); /* compute average angle */
ss=ww*day/(2*pi); /* convert to seconds */
If ss<0 Then ss=ss+day; /* avoid negative value */
m=ss/60; /* split into hh mm ss */
s=ss-m*60;
h=m/60;
m=m-h*60;
Put Edit(h,':',m,':',s)(Skip,3(p'99',a));
t2a: Procedure(t) Returns(Bin Float(18)); /* convert time to angle */
Dcl t Char(8);
Dcl 1 tt Based(addr(t)),
2 hh Pic'99',
2 * Char(1),
2 mm Pic'99',
2 * Char(1),
2 ss Pic'99';
Dcl sec Bin Fixed(31);
Dcl a Bin Float(18);
sec=(hh*60+mm)*60+ss;
If sec>(day/2) Then
sec=sec-day;
a=2*pi*sec/day;
Return (a);
End;
End;</syntaxhighlight>
{{out}}
<pre>23:47:43</pre>
=={{header|PowerShell}}==
<syntaxhighlight lang="powershell">
function Get-MeanTimeOfDay
{
[CmdletBinding()]
[OutputType([timespan])]
Param
(
[Parameter(Mandatory=$true,
ValueFromPipeline=$true,
ValueFromPipelineByPropertyName=$true)]
[ValidatePattern("(?:2[0-3]|[01]?[0-9])[:.][0-5]?[0-9][:.][0-5]?[0-9]")]
[string[]]
$Time
)
Begin
{
[double[]]$angles = @()
function ConvertFrom-Time ([timespan]$Time)
{
[double]((360 * $Time.Hours / 24) + (360 * $Time.Minutes / (24 * 60)) + (360 * $Time.Seconds / (24 * 3600)))
}
function ConvertTo-Time ([double]$Angle)
{
$t = New-TimeSpan -Hours ([int](24 * 60 * 60 * $Angle / 360) / 3600) `
-Minutes (([int](24 * 60 * 60 * $Angle / 360) % 3600 - [int](24 * 60 * 60 * $Angle / 360) % 60) / 60) `
-Seconds ([int]((24 * 60 * 60 * $Angle / 360) % 60))
if ($t.Days -gt 0)
{
return ($t - (New-TimeSpan -Hours 1))
}
$t
}
function Get-MeanAngle ([double[]]$Angles)
{
[double]$x,$y = 0
for ($i = 0; $i -lt $Angles.Count; $i++)
{
$x += [Math]::Cos($Angles[$i] * [Math]::PI / 180)
$y += [Math]::Sin($Angles[$i] * [Math]::PI / 180)
}
$result = [Math]::Atan2(($y / $Angles.Count), ($x / $Angles.Count)) * 180 / [Math]::PI
if ($result -lt 0)
{
return ($result + 360)
}
$result
}
}
Process
{
$angles += ConvertFrom-Time $_
}
End
{
ConvertTo-Time (Get-MeanAngle $angles)
}
}
</syntaxhighlight>
<syntaxhighlight lang="powershell">
[timespan]$meanTimeOfDay = "23:00:17","23:40:20","00:12:45","00:17:19" | Get-MeanTimeOfDay
"Mean time is {0}" -f (Get-Date $meanTimeOfDay.ToString()).ToString("hh:mm:ss tt")
</syntaxhighlight>
{{Out}}
<pre>
Mean time is 11:47:43 PM
</pre>
=={{header|Python}}==
<
from math import radians, degrees
Line 282 ⟶ 2,136:
if __name__ == '__main__':
print( mean_time(["23:00:17", "23:40:20", "00:12:45", "00:17:19"]) )</
{{out}}
<pre>23:47:43</pre>
=={{header|Racket}}==
<syntaxhighlight lang="racket">
#lang racket
(define (mean-angle/radians as)
(define n (length as))
(atan (* (/ 1 n) (for/sum ([αj as]) (sin αj)))
(* (/ 1 n) (for/sum ([αj as]) (cos αj)))))
(define (mean-time times)
(define secs/day (* 60 60 24))
(define (time->deg time)
(/ (for/fold ([sum 0]) ([t (map string->number (string-split time ":"))])
(+ (* 60 sum) t))
secs/day 1/360 (/ 180 pi)))
(define secs
(modulo (inexact->exact (round (* (mean-angle/radians (map time->deg times))
(/ 180 pi) 1/360 secs/day)))
secs/day))
(let loop ([s secs] [ts '()])
(if (zero? s) (string-join ts ":")
(let-values ([(q r) (quotient/remainder s 60)])
(loop q (cons (~r r #:min-width 2 #:pad-string "0") ts))))))
(mean-time '("23:00:17" "23:40:20" "00:12:45" "00:17:19"))
</syntaxhighlight>
{{out}}
<pre>"23:47:43"</pre>
=={{header|Raku}}==
(formerly Perl 6)
{{works with|Rakudo|2015.12}}
<syntaxhighlight lang="raku" line>sub tod2rad($_) { [+](.comb(/\d+/) Z* 3600,60,1) * tau / 86400 }
sub rad2tod ($r) {
my $x = $r * 86400 / tau;
(($x xx 3 Z/ 3600,60,1) Z% 24,60,60).fmt('%02d',':');
}
sub phase ($c) { $c.polar[1] }
sub mean-time (@t) { rad2tod phase [+] map { cis tod2rad $_ }, @t }
my @times = ["23:00:17", "23:40:20", "00:12:45", "00:17:19"];
say "{ mean-time(@times) } is the mean time of @times[]";</syntaxhighlight>
{{out}}
<pre>
23:47:43 is the mean time of 23:00:17 23:40:20 00:12:45 00:17:19
</pre>
=={{header|REXX}}==
<syntaxhighlight lang="rexx">/* REXX ---------------------------------------------------------------
* 25.06.2014 Walter Pachl
* taken from ooRexx using my very aged sin/cos/artan functions
*--------------------------------------------------------------------*/
times='23:00:17 23:40:20 00:12:45 00:17:19'
sum=0
day=86400
pi=3.14159265358979323846264
x=0
y=0
Do i=1 To words(times) /* loop over times */
time.i=word(times,i) /* pick a time */
alpha.i=t2a(time.i) /* convert to angle (radians) */
/* Say time.i format(alpha.i,6,9) */
x=x+sin(alpha.i) /* accumulate sines */
y=y+cos(alpha.i) /* accumulate cosines */
End
ww=arctan(x/y) /* compute average angle */
ss=ww*86400/(2*pi) /* convert to seconds */
If ss<0 Then ss=ss+day /* avoid negative value */
m=ss%60 /* split into hh mm ss */
s=ss-m*60
h=m%60
m=m-h*60
Say f2(h)':'f2(m)':'f2(s) /* show the mean time */
Exit
t2a: Procedure Expose day pi /* convert time to angle */
Parse Arg hh ':' mm ':' ss
sec=(hh*60+mm)*60+ss
If sec>(day/2) Then
sec=sec-day
a=2*pi*sec/day
Return a
f2: return right(format(arg(1),2,0),2,0)
sin: Procedure Expose pi
Parse Arg x
prec=digits()
Numeric Digits (2*prec)
Do While x>pi
x=x-pi
End
Do While x<-pi
x=x+pi
End
o=x
u=1
r=x
Do i=3 By 2
ra=r
o=-o*x*x
u=u*i*(i-1)
r=r+(o/u)
If r=ra Then Leave
End
Numeric Digits prec
Return r+0
cos: Procedure Expose pi
Parse Arg x
prec=digits()
Numeric Digits (2*prec)
Numeric Fuzz 3
o=1
u=1
r=1
Do i=1 By 2
ra=r
o=-o*x*x
u=u*i*(i+1)
r=r+(o/u)
If r=ra Then Leave
End
Numeric Digits prec
Return r+0
arctan: Procedure
Parse Arg x
prec=digits()
Numeric Digits (2*prec)
Numeric Fuzz 3
o=x
u=1
r=x
k=0
Do i=3 By 2
ra=r
o=-o*x*x
r=r+(o/i)
If r=ra Then
Leave
k=k+1
If k//1000=0 Then
Say i left(r,40) format(abs(o/i),15,5)
End
Numeric Digits (prec)
Return r+0</syntaxhighlight>
{{out}}
<pre>23:47:43</pre>
=={{header|RPL}}==
{{works with|Halcyon Calc|4.2.7}}
≪ → angles
≪ 0 1 angles SIZE '''FOR''' j
1 angles j GET R→C P→R + '''NEXT'''
angles SIZE / ARG
≫ ≫ ''''MEANG'''' STO
≪ → times
≪ { } 1 times SIZE '''FOR''' j
1 times j GET HMS→ 15 * + '''NEXT'''
'''MEANG''' 15 / 24 MOD →HMS 4 FIX RND STD
≫ ≫ ''''MTIME'''' STO
{23.0017 23.4020 0.1245 0.1719 } '''MTIME'''
{{out}}
<pre>
1: 23.4743
</pre>
=={{header|Ruby}}==
Using the methods at [[http://rosettacode.org/wiki/Averages/Mean_angle#Ruby|Averages/Mean angle]]
<syntaxhighlight lang="ruby">def time2deg(t)
raise "invalid time" unless m = t.match(/^(\d\d):(\d\d):(\d\d)$/)
hh,mm,ss = m[1..3].map {|e| e.to_i}
raise "invalid time" unless (0..23).include? hh and
(0..59).include? mm and
(0..59).include? ss
(hh*3600 + mm*60 + ss) * 360 / 86400.0
end
def deg2time(d)
sec = (d % 360) * 86400 / 360.0
"%02d:%02d:%02d" % [sec/3600, (sec%3600)/60, sec%60]
end
def mean_time(times)
deg2time(mean_angle(times.map {|t| time2deg t}))
end
puts mean_time ["23:00:17", "23:40:20", "00:12:45", "00:17:19"]</syntaxhighlight>
{{out}}
23:47:43
=={{header|Run BASIC}}==
<syntaxhighlight lang="runbasic">global pi
pi = acs(-1)
Print "Average of:"
for i = 1 to 4
read t$
print t$
a = time2angle(t$)
ss = ss+sin(a)
sc = sc+cos(a)
next
a = atan2(ss,sc)
if a < 0 then a = a + 2 * pi
print "is ";angle2time$(a)
end
data "23:00:17", "23:40:20", "00:12:45", "00:17:19"
function nn$(n)
nn$ = right$("0";n, 2)
end function
function angle2time$(a)
a = int(a / 2 / pi * 24 * 60 * 60)
ss = a mod 60
a = int(a / 60)
mm=a mod 60
hh=int(a/60)
angle2time$=nn$(hh);":";nn$(mm);":";nn$(ss)
end function
function time2angle(time$)
hh=val(word$(time$,1,":"))
mm=val(word$(time$,2,":"))
ss=val(word$(time$,3,":"))
time2angle=2*pi*(60*(60*hh+mm)+ss)/24/60/60
end function
function atan2(y, x)
if y <> 0 then
atan2 = (2 * (atn((sqr((x * x) + (y * y)) - x)/ y)))
else
atan2 = (y=0)*(x<0)*pi
end if
End Function</syntaxhighlight>
=={{header|Rust}}==
<syntaxhighlight lang="rust">
use std::f64::consts::PI;
#[derive(Debug, PartialEq, Eq)]
struct Time {
h: u8,
m: u8,
s: u8,
}
impl Time {
/// Create a Time from equivalent radian measure
fn from_radians(mut rads: f64) -> Time {
rads %= 2.0 * PI;
if rads < 0.0 {
rads += 2.0 * PI
}
Time {
h: (rads * 12.0 / PI) as u8,
m: ((rads * 720.0 / PI) % 60.0) as u8,
s: ((rads * 43200.0 / PI) % 60.0).round() as u8,
}
}
/// Create a Time from H/M/S
fn from_parts(h: u8, m: u8, s: u8) -> Result<Time, ()> {
if h > 23 || m > 59 || s > 59 {
return Err(());
}
Ok(Time { h, m, s })
}
/// Return time as measure in radians
fn as_radians(&self) -> f64 {
((self.h as f64 / 12.0) + (self.m as f64 / 720.0) + (self.s as f64 / 43200.0)) * PI
}
}
/// Compute the mean time from a slice of times
fn mean_time(times: &[Time]) -> Time {
// compute sum of sines and cosines
let (ss, sc) = times
.iter()
.map(Time::as_radians)
.map(|a| (a.sin(), a.cos()))
.fold((0.0, 0.0), |(ss, sc), (s, c)| (ss + s, sc + c));
// scaling does not matter for atan2, meaning we do not have to divide sums by len
Time::from_radians(ss.atan2(sc))
}
fn main() {
let times = [
Time::from_parts(23, 00, 17).unwrap(),
Time::from_parts(23, 40, 20).unwrap(),
Time::from_parts(00, 12, 45).unwrap(),
Time::from_parts(00, 17, 19).unwrap(),
];
let mean = mean_time(×);
println!("{:02}:{:02}:{:02}", mean.h, mean.m, mean.s);
}
</syntaxhighlight>
{{out}}
<pre>
23:47:43
</pre>
=={{header|Scala}}==
{{libheader|java.time.LocalTime}}<syntaxhighlight lang="scala">import java.time.LocalTime
import scala.compat.Platform
trait MeanAnglesComputation {
import scala.math.{Pi, atan2, cos, sin}
def meanAngle(angles: List[Double], convFactor: Double = 180.0 / Pi) = {
val sums = angles.foldLeft((.0, .0))((r, c) => {
val rads = c / convFactor
(r._1 + sin(rads), r._2 + cos(rads))
})
val result = atan2(sums._1, sums._2)
(result + (if (result.signum == -1) 2 * Pi else 0.0)) * convFactor
}
}
object MeanBatTime extends App with MeanAnglesComputation {
val dayInSeconds = 60 * 60 * 24
def times = batTimes.map(t => afterMidnight(t).toDouble)
def afterMidnight(twentyFourHourTime: String) = {
val t = LocalTime.parse(twentyFourHourTime)
(if (t.isBefore(LocalTime.NOON)) dayInSeconds else 0) + LocalTime.parse(twentyFourHourTime).toSecondOfDay
}
def batTimes = List("23:00:17", "23:40:20", "00:12:45", "00:17:19")
assert(LocalTime.MIN.plusSeconds(meanAngle(times, dayInSeconds).round).toString == "23:47:40")
println(s"Successfully completed without errors. [total ${Platform.currentTime - executionStart} ms]")
}</syntaxhighlight>
=={{header|Scheme}}==
{{libheader|Scheme/SRFIs}}
To be self-contained, this starts with the functions from [[Averages/Mean angle]]
<syntaxhighlight lang="scheme">
(import (scheme base)
(scheme inexact)
(scheme read)
(scheme write)
(srfi 1)) ; for fold
;; functions copied from "Averages/Mean angle" task
(define (average l)
(/ (fold + 0 l) (length l)))
(define pi 3.14159265358979323846264338327950288419716939937510582097)
(define (radians a)
(* pi 1/180 a))
(define (degrees a)
(* 180 (/ 1 pi) a))
(define (mean-angle angles)
(let* ((angles (map radians angles))
(cosines (map cos angles))
(sines (map sin angles)))
(degrees (atan (average sines) (average cosines)))))
;; -- new functions for this task
(define (time->angle time)
(let* ((time2 ; replaces : with space in string
(string-map (lambda (c) (if (char=? c #\:) #\space c)) time))
(string-port (open-input-string time2))
(hour (read string-port))
(minutes (read string-port))
(seconds (read string-port)))
(/ (* 360 (+ (* hour 3600) (* minutes 60) seconds))
(* 24 60 60))))
(define (angle->time angle)
(let* ((nom-angle (if (negative? angle) (+ 360 angle) angle))
(time (/ (* nom-angle 24 60 60) 360))
(hour (exact (floor (/ time 3600))))
(minutes (exact (floor (/ (- time (* 3600 hour)) 60))))
(seconds (exact (floor (- time (* 3600 hour) (* 60 minutes))))))
(string-append (number->string hour)
":"
(number->string minutes)
":"
(number->string seconds))))
(define (mean-time-of-day times)
(angle->time (mean-angle (map time->angle times))))
(write (mean-time-of-day '("23:00:17" "23:40:20" "00:12:45" "00:17:19")))
(newline)
</syntaxhighlight>
{{out}}
<pre>
"23:47:43"
</pre>
=={{header|Sidef}}==
{{trans|Ruby}}
Using the '''mean_angle()''' function from: [http://rosettacode.org/wiki/Averages/Mean_angle#Sidef "Averages/Mean angle"]
<syntaxhighlight lang="ruby">func time2deg(t) {
(var m = t.match(/^(\d\d):(\d\d):(\d\d)$/)) || die "invalid time"
var (hh,mm,ss) = m.cap.map{.to_i}...
((hh ~~ 24.range) && (mm ~~ 60.range) && (ss ~~ 60.range)) || die "invalid time"
(hh*3600 + mm*60 + ss) * 360 / 86400
}
func deg2time(d) {
var sec = ((d % 360) * 86400 / 360)
"%02d:%02d:%02d" % (sec/3600, (sec%3600)/60, sec%60)
}
func mean_time(times) {
deg2time(mean_angle(times.map {|t| time2deg(t)}))
}
say mean_time(["23:00:17", "23:40:20", "00:12:45", "00:17:19"])</syntaxhighlight>
{{out}}
<pre>23:47:43</pre>
=={{header|SQL}}/{{header|PostgreSQL}}==
{{trans|Python}}
<syntaxhighlight lang="sql">
--Setup table for testing
CREATE TABLE time_table(times time);
INSERT INTO time_table values ('23:00:17'::time),('23:40:20'::time),('00:12:45'::time),('00:17:19'::time)
--Compute mean time
SELECT to_timestamp((degrees(atan2(AVG(sin),AVG(cos))))* (24*60*60)/360)::time
FROM
(SELECT
cos(radians(t*360/(24*60*60))),sin(radians(t*360/(24*60*60)))
FROM
(SELECT EXTRACT(epoch from times) t
FROM time_table) T1
)T2</syntaxhighlight>
Output:
<pre>
23:47:43.361529
</pre>
=={{header|Swift}}==
<syntaxhighlight lang="swift">import Foundation
@inlinable public func d2r<T: FloatingPoint>(_ f: T) -> T { f * .pi / 180 }
@inlinable public func r2d<T: FloatingPoint>(_ f: T) -> T { f * 180 / .pi }
public func meanOfAngles(_ angles: [Double]) -> Double {
let cInv = 1 / Double(angles.count)
let (y, x) =
angles.lazy
.map(d2r)
.map({ (sin($0), cos($0)) })
.reduce(into: (0.0, 0.0), { $0.0 += $1.0; $0.1 += $1.1 })
return r2d(atan2(cInv * y, cInv * x))
}
struct DigitTime {
var hour: Int
var minute: Int
var second: Int
init?(fromString str: String) {
let split = str.components(separatedBy: ":").compactMap(Int.init)
guard split.count == 3 else {
return nil
}
(hour, minute, second) = (split[0], split[1], split[2])
}
init(fromDegrees angle: Double) {
let totalSeconds = 24 * 60 * 60 * angle / 360
second = Int(totalSeconds.truncatingRemainder(dividingBy: 60))
minute = Int((totalSeconds.truncatingRemainder(dividingBy: 3600) - Double(second)) / 60)
hour = Int(totalSeconds / 3600)
}
func toDegrees() -> Double {
return 360 * Double(hour) / 24.0 + 360 * Double(minute) / (24 * 60.0) + 360 * Double(second) / (24 * 3600.0)
}
}
extension DigitTime: CustomStringConvertible {
var description: String { String(format: "%02i:%02i:%02i", hour, minute, second) }
}
let times = ["23:00:17", "23:40:20", "00:12:45", "00:17:19"].compactMap(DigitTime.init(fromString:))
guard times.count == 4 else {
fatalError()
}
let meanTime = DigitTime(fromDegrees: 360 + meanOfAngles(times.map({ $0.toDegrees() })))
print("Given times \(times), the mean time is \(meanTime)")</syntaxhighlight>
{{out}}
<pre>Given times [23:00:17, 23:40:20, 00:12:45, 00:17:19], the mean time is 23:47:43</pre>
=={{header|Tcl}}==
<syntaxhighlight lang="tcl">proc meanTime {times} {
set secsPerRad [expr {60 * 60 * 12 / atan2(0,-1)}]
set sumSin [set sumCos 0.0]
foreach t $times {
# Convert time to count of seconds from midnight
scan $t "%02d:%02d:%02d" h m s
incr s [expr {[incr m [expr {$h * 60}]] * 60}]
# Feed into averaging
set sumSin [expr {$sumSin + sin($s / $secsPerRad)}]
set sumCos [expr {$sumCos + cos($s / $secsPerRad)}]
}
# Don't need to divide by counts; atan2() cancels that out
set a [expr {round(atan2($sumSin, $sumCos) * $secsPerRad)}]
# Convert back to human-readable
format "%02d:%02d:%02d" [expr {$a / 60 / 60 % 24}] [expr {$a / 60 % 60}] [expr {$a % 60}]
}
puts [meanTime {23:00:17 23:40:20 00:12:45 00:17:19}]</syntaxhighlight>
{{out}}
23:47:43
=={{header|VBA}}==
Uses Excel and [[Averages/Mean_angle#VBA|mean angle]].
<syntaxhighlight lang="vb">Public Sub mean_time()
Dim angles() As Double
s = [{"23:00:17","23:40:20","00:12:45","00:17:19"}]
For i = 1 To UBound(s)
s(i) = 360 * TimeValue(s(i))
Next i
Debug.Print Format(mean_angle(s) / 360 + 1, "hh:mm:ss")
End Sub</syntaxhighlight>{{out}}
<pre>23:47:43</pre>
=={{header|Visual Basic .NET}}==
{{trans|C#}}
<syntaxhighlight lang="vbnet">Module Module1
Function TimeToDegrees(time As TimeSpan) As Double
Return 360 * time.Hours / 24.0 + 360 * time.Minutes / (24 * 60.0) + 360 * time.Seconds / (24 * 3600.0)
End Function
Function DegreesToTime(angle As Double) As TimeSpan
Return New TimeSpan((24 * 60 * 60 * angle \ 360) \ 3600, ((24 * 60 * 60 * angle \ 360) Mod 3600 - (24 * 60 * 60 * angle \ 360) Mod 60) \ 60, (24 * 60 * 60 * angle \ 360) Mod 60)
End Function
Function MeanAngle(angles As List(Of Double)) As Double
Dim y_part = 0.0
Dim x_part = 0.0
Dim numItems = angles.Count
For Each angle In angles
x_part += Math.Cos(angle * Math.PI / 180)
y_part += Math.Sin(angle * Math.PI / 180)
Next
Return Math.Atan2(y_part / numItems, x_part / numItems) * 180 / Math.PI
End Function
Sub Main()
Dim digitimes As New List(Of Double)
Dim digitime As TimeSpan
Dim input As String
Console.WriteLine("Enter times, end with no input: ")
Do
input = Console.ReadLine
If Not String.IsNullOrWhiteSpace(input) Then
If TimeSpan.TryParse(input, digitime) Then
digitimes.Add(TimeToDegrees(digitime))
Else
Console.WriteLine("Seems this is wrong input: ingnoring time")
End If
End If
Loop Until String.IsNullOrWhiteSpace(input)
If digitimes.Count > 0 Then
Console.WriteLine("The mean time is : {0}", DegreesToTime(360 + MeanAngle(digitimes)))
End If
End Sub
End Module</syntaxhighlight>
{{out}}
<pre>Enter times, end with no input:
23:00:17
23:40:20
00:12:45
00:17:19
The mean time is : 23:47:43</pre>
=={{header|V (Vlang)}}==
{{trans|Wren}}
<syntaxhighlight lang="v (vlang)">import math
const inputs = ["23:00:17", "23:40:20", "00:12:45", "00:17:19"]
fn main() {
angles := inputs.map(time_to_degs(it))
println('Mean time of day is: ${degs_to_time(mean_angle(angles))}')
}
fn mean_angle(angles []f64) f64 {
n := angles.len
mut sin_sum := f64(0)
mut cos_sum := f64(0)
for angle in angles {
sin_sum += math.sin(angle * math.pi / 180)
cos_sum += math.cos(angle * math.pi / 180)
}
return math.atan2(sin_sum/n, cos_sum/n) * 180 / math.pi
}
fn degs_to_time(dd f64) string{
mut d := dd
for d < 0 {
d += 360
}
mut s := math.round(d * 240)
h := math.floor(s/3600)
mut m := math.fmod(s, 3600)
s = math.fmod(m, 60)
m = math.floor(m / 60)
return "${h:02}:${m:02}:${s:02}"
}
fn time_to_degs(time string) f64 {
t := time.split(":")
h := t[0].f64() * 3600
m := t[1].f64() * 60
s := t[2].f64()
return (h + m + s) / 240
}</syntaxhighlight>
{{out}}
<pre>
Mean time of day is: 23:47:43
</pre>
=={{header|Wren}}==
{{libheader|Wren-fmt}}
<syntaxhighlight lang="wren">import "./fmt" for Fmt
var timeToDegs = Fn.new { |time|
var t = time.split(":")
var h = Num.fromString(t[0]) * 3600
var m = Num.fromString(t[1]) * 60
var s = Num.fromString(t[2])
return (h + m + s) / 240
}
var degsToTime = Fn.new { |d|
while (d < 0) d = d + 360
var s = (d * 240).round
var h = (s/3600).floor
var m = s % 3600
s = m % 60
m = (m / 60).floor
return Fmt.swrite("$2d:$2d:$2d", h, m, s)
}
var meanAngle = Fn.new { |angles|
var n = angles.count
var sinSum = 0
var cosSum = 0
for (angle in angles) {
sinSum = sinSum + (angle * Num.pi / 180).sin
cosSum = cosSum + (angle * Num.pi / 180).cos
}
return (sinSum/n).atan(cosSum/n) * 180 / Num.pi
}
var times = ["23:00:17", "23:40:20", "00:12:45", "00:17:19"]
var angles = times.map { |t| timeToDegs.call(t) }.toList
System.print("Mean time of day is : %(degsToTime.call(meanAngle.call(angles)))")</syntaxhighlight>
{{out}}
<pre>
Mean time of day is : 23:47:43
</pre>
=={{header|XPL0}}==
<
proc NumOut(N); \Display 2-digit N with leading zero
Line 324 ⟶ 2,877:
];
TimeOut(MeanTime([4, [23,00,17], [23,40,20], [00,12,45], [00,17,19]]))</
{{out}}
<pre>
23:47:43
</pre>
=={{header|Yabasic}}==
{{trans|Phix}}
<syntaxhighlight lang="yabasic">sub atan2(y, x)
return 2 * atan((sqrt(x **2 + y ** 2) - x) / y)
end sub
sub MeanAngle(angles())
local x, y, ai_rad, l, i
l = arraysize(angles(), 1)
for i = 1 to l
ai_rad = angles(i) * PI / 180
x = x + cos(ai_rad)
y = y + sin(ai_rad)
next i
if abs(x) < 1e-16 return false
return atan2(y, x) * 180 / PI
end sub
sub toSecAngle(hours, minutes, seconds)
return ((hours * 60 + minutes) * 60 + seconds) / (24 * 60 * 60) * 360
end sub
dim Times(4)
Times(1) = toSecAngle(23,00,17)
Times(2) = toSecAngle(23,40,20)
Times(3) = toSecAngle(00,12,45)
Times(4) = toSecAngle(00,17,19)
sub toHMS$(t)
local s$
if t then
if t < 0 t = t + 360
t = 24 * 60 * 60 * t / 360
s$ = str$(int(t / 3600), "%02g") + ":" + str$(int(mod(t, 3600) / 60), "%02g") + ":" + str$(int(mod(t, 60)), "%02g")
else
s$ = "not meaningful"
end if
return s$
end sub
print "Mean Time is ", toHMS$(MeanAngle(Times()))
// Output: Mean Time is 23:47:43
</syntaxhighlight>
=={{header|zkl}}==
This solution is a bit greasy, combining the solution
to task "Averages/Mean angle" and some on-the-fly
time-to-angle and back conversions.
<syntaxhighlight lang="zkl">var D=Time.Date;
fcn meanT(t1,t2,etc){
ts:=vm.arglist.apply(fcn(hms){
(D.toFloat(hms.split(":").xplode())*15).toRad()
});
n:=ts.len();
mt:=(ts.apply("sin").sum(0.0)/n)
.atan2(ts.apply("cos").sum(0.0)/n)
.toDeg() /15;
if(mt<0) mt+=24; //-0.204622-->23.7954
D.toHour(mt).concat(":")
}</syntaxhighlight>
Time.Date.toFloat/toHour convert 24hr HMS to fractional time and back. Multiplying fractional time by 360/24=15 yields angle.
{{out}}
<pre>
meanT("23:00:17", "23:40:20", "00:12:45", "00:17:19")
23:47:43
</pre>
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