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# Time a function

Time a function
You are encouraged to solve this task according to the task description, using any language you may know.

Write a program which uses a timer (with the least granularity available on your system) to time how long a function takes to execute.

Whenever possible, use methods which measure only the processing time used by the current process; instead of the difference in system time between start and finish, which could include time used by other processes on the computer.

This task is intended as a subtask for Measure relative performance of sorting algorithms implementations.

## 8051 Assembly

Using a timer requires knowledge on two things: the oscillator frequency (which limits the maximum precision) and the desired precision. This code uses a common crystal of 11.0592MHz - but provides values for a few others as examples. This code also uses a precision of 4 bits (2^(-4) = 0.0625 seconds). Those familiar with binary can think of this as a right shift of 4 of the multi-byte value, where the low 4 bits represent the fraction of a second, and the remaining bits represent whole seconds. The maximum time value depends on the number of bytes used and the precision. For x bytes and p precision, the maximum value you can count to is (256^x - 1) * 2^(-p).

`TC	EQU	8 ; number of counter registersTSTART	EQU	08h ; first register of timer counterTEND	EQU	TSTART + TC - 1 ; end register of timer counter; Note: The multi-byte value is stored in Big-endian ; Some timer reloads_6H	EQU	085h ; 6MHz_6L	EQU	0edh_12H	EQU	00bh ; 12MHz_12L	EQU	0dbh_110592H	EQU	01eh ; 11.0592MHz_110592L	EQU	0ffh ; How to calculate timer reload (e.g. for 11.0592MHz):; Note: 1 machine cycle takes 12 oscillator periods; 11.0592MHz / 12 * 0.0625 seconds = 57,600 cycles = e100h; ffffh - e100h = NOT e100h = 1effh ; assuming a 11.0592MHz crystalTIMERH	EQU	_110592HTIMERL	EQU	_110592L ;; some timer macros (using timer0)start_timer macro	setb tr0endmstop_timer macro	clr tr0endmreset_timer macro	mov tl0, #TIMERL	mov th0, #TIMERHendm increment_counter macro ;; increment counter (multi-byte increment)	push psw	push acc	push 0 ; r0	mov r0, #TEND+1	setb cinc_reg:	dec r0	clr a	addc a, @r0	mov @r0, a	jnc inc_reg_	; end prematurally if the higher bytes are unchanged	cjne r0, #TSTART, inc_reginc_reg_:	; if the carry is set here then the multi byte value has overflowed	pop 0	pop acc	pop pswendm	 ORG RESET	jmp initORG TIMER0	jmp timer_0 timer_0: ; interrupt every 6.25ms	stop_timer		; we only want to time the function	reset_timer	increment_counter	start_timer	reti init:	mov sp, #TEND	setb ea			; enable interrupts	setb et0		; enable timer0 interrupt	mov tmod, #01h		; timer0 16-bit mode	reset_timer 	; reset timer counter registers	clr a	mov r0, #TSTARTclear:	mov @r0, a	inc r0	cjne r0, #TEND, clear 	start_timer	call function		; the function to time	stop_timer 	; at this point the registers from TSTART	; through TEND indicate the current time	; multiplying the 8/16/24/etc length value by 0.0625 (2^-4) gives 	; the elapsed number of seconds	; e.g. if the three registers were 02a0f2h then the elapsed time is:	; 02a0f2h = 172,274 and 172,274 * 0.0625 = 10,767.125 seconds	;	; Or alternatively:	; (high byte) 02h = 2 and 2 * 2^(16-4) = 8192	; (mid byte) a0h = 160 and 160 * 2^(8-4) = 2560	; (low byte) f2h = 242 and 242 * 2^(0-4) = 15.125	; 8192 + 2560 + 15.125 = 10,767.125 seconds 	jmp \$ function:	; do whatever here	ret END `

## ACL2

`(time\$ (nthcdr 9999999 (take 10000000 nil)))`

Output (for Clozure):

```; (EV-REC *RETURN-LAST-ARG3* ...) took
; 2.53 seconds realtime, 2.48 seconds runtime
; (160,001,648 bytes allocated).
(NIL)```

`with Ada.Calendar; use Ada.Calendar;with Ada.Text_Io; use Ada.Text_Io; procedure Query_Performance is   type Proc_Access is access procedure(X : in out Integer);   function Time_It(Action : Proc_Access; Arg : Integer) return Duration is      Start_Time : Time := Clock;      Finis_Time : Time;      Func_Arg : Integer := Arg;   begin      Action(Func_Arg);      Finis_Time := Clock;      return Finis_Time - Start_Time;   end Time_It;   procedure Identity(X : in out Integer) is   begin      X := X;   end Identity;   procedure Sum (Num : in out Integer) is   begin      for I in 1..1000 loop         Num := Num + I;      end loop;   end Sum;   Id_Access : Proc_Access := Identity'access;   Sum_Access : Proc_Access := Sum'access; begin   Put_Line("Identity(4) takes" & Duration'Image(Time_It(Id_Access, 4)) & " seconds.");   Put_Line("Sum(4) takes:" & Duration'Image(Time_It(Sum_Access, 4)) & " seconds.");end Query_Performance;`

### Example

```Identity(4) takes 0.000001117 seconds.
Sum(4) takes: 0.000003632 seconds.
```

## Aime

`integeridentity(integer x){    x;}  integersum(integer c){    integer s;     s = 0;    while (c) {	s += c;	c -= 1;    }     s;}  realtime_f(integer (*fp)(integer), integer fa){    date f, s;    time t;     s.now;     fp(fa);     f.now;     t.ddiff(f, s);     t.microsecond / 1000000r;}  integermain(void){    o_real(6, time_f(identity, 1));    o_text(" seconds\n");    o_real(6, time_f(sum, 1000000));    o_text(" seconds\n");     0;}`

## ARM Assembly

Works with: as version Raspberry Pi
` /* ARM assembly Raspberry PI  *//*  program fcttime.s   */ /* Constantes    */.equ STDOUT, 1     @ Linux output console.equ EXIT,   1     @ Linux syscall.equ WRITE,  4     @ Linux syscall .equ N1, 1000000   @ loop number.equ NBMEASURE, 10 @ measure number /*********************************//* Initialized data              *//*********************************/.dataszMessError:       .asciz "Error detected !!!!. \n"szMessSep:         .asciz "****************************\n"szMessTemps:       .ascii "Function time : "sSecondes:         .fill 10,1,' '                   .ascii " s "sMicroS:           .fill 10,1,' '                   .asciz " micros\n" szCarriageReturn:  .asciz "\n"/*********************************//* UnInitialized data            *//*********************************/.bss .align 4dwDebut:           .skip 8dwFin:             .skip 8/*********************************//*  code section                 *//*********************************/.text.global main main:                                     @ entry of program     adr r0,mult                           @ function address to measure    mov r1,#1                             @ parameter 1 function    mov r2,#2                             @ parameter 2 function    bl timeMesure    cmp r0,#0    blt 99f    adr r0,sum                            @ function address to measure    mov r1,#1    mov r2,#2    bl timeMesure    cmp r0,#0    blt 99f    b 100f99:    @ error    ldr r0,iAdrszMessError    bl affichageMess       100:                                       @ standard end of the program     mov r0, #0                             @ return code    mov r7, #EXIT                          @ request to exit program    svc #0                                 @ perform the system call iAdrszMessError:          .int szMessErroriAdrszCarriageReturn:     .int szCarriageReturn/**************************************************************//*   examble function sum                                     *//**************************************************************//* r0 contains op 1     *//* r1 contains op 2     */sum:    push {lr}                  @ save registres    add r0,r1100:    pop {lr}                   @ restaur registers    bx lr                      @ function return /**************************************************************//*   exemple execution multiplication                         *//**************************************************************//* r0 contains op 1     *//* r1 contains op 2     */mult:    push {lr}                  @ save registres    mul r0,r1,r0100:    pop {lr}                   @ restaur registers    bx lr                      @ function return /**************************************************************//*   Procedure for measuring the execution time of a routine  *//**************************************************************//* r0 contains the function address     */timeMesure:    push {r1-r8,lr}                      @ save registres    mov r4,r0                            @ save function address    mov r5,r1                            @ save param 1    mov r6,r2                            @ save param 2    mov r8,#01:    ldr r0,iAdrdwDebut                   @ start time area    mov r1,#0    mov r7, #0x4e                        @ call system gettimeofday    svc #0     cmp r0,#0                            @ error ?    blt 100f                             @ return error    ldr r7,iMax                          @ run number    mov r0,r5                            @ param function 1    mov r1,r6                            @ param function 22:                                       @ loop    blx r4                               @ call of the function to be measured    subs r7,#1                           @ decrement run    bge 2b                               @ loop if not zero    @    ldr r0,iAdrdwFin                     @ end time area    mov r1,#0    mov r7, #0x4e                        @ call system gettimeofday    svc #0     cmp r0,#0                            @ error ?    blt 100f                             @ return error                                         @ compute time    ldr r0,iAdrdwDebut                   @ start time area    //vidmemtit mesure r0 2    ldr r2,[r0]                          @ secondes    ldr r3,[r0,#4]                       @ micro secondes    ldr r0,iAdrdwFin                     @ end time area    ldr r1,[r0]                          @ secondes    ldr r0,[r0,#4]                       @ micro secondes    sub r2,r1,r2                         @ secondes number    subs r3,r0,r3                        @ microsecondes number    sublt r2,#1                          @ if negative sub 1 seconde to secondes    ldr r1,iSecMicro    addlt r3,r1                          @ and add 1000000 to microsecondes number    mov r0,r2                            @ conversion secondes     ldr r1,iAdrsSecondes    bl conversion10    mov r0,r3                            @ conversion microsecondes    ldr r1,iAdrsMicroS    bl conversion10    ldr r0,iAdrszMessTemps    bl affichageMess                     @ display message    add r8,#1    cmp r8,#NBMEASURE    ble 1b    ldr r0,iAdrszMessSep                 @ display separator    bl affichageMess   100:    pop {r1-r8,lr}                       @ restaur registers    bx lr                                @ function returniMax:                 .int N1 iAdrdwDebut:          .int dwDebutiAdrdwFin:            .int dwFiniSecMicro:            .int 1000000iAdrsSecondes:        .int sSecondesiAdrsMicroS:          .int sMicroSiAdrszMessTemps:      .int szMessTempsiAdrszMessSep:        .int szMessSep /******************************************************************//*     display text with size calculation                         */ /******************************************************************//* r0 contains the address of the message */affichageMess:    push {r0,r1,r2,r7,lr}                   @ save  registres    mov r2,#0                               @ counter length 1:                                          @ loop length calculation     ldrb r1,[r0,r2]                         @ read octet start position + index     cmp r1,#0                               @ if 0 its over     addne r2,r2,#1                          @ else add 1 in the length     bne 1b                                  @ and loop                                             @ so here r2 contains the length of the message     mov r1,r0                               @ address message in r1     mov r0,#STDOUT                          @ code to write to the standard output Linux     mov r7, #WRITE                          @ code call system "write"     svc #0                                  @ call systeme     pop {r0,r1,r2,r7,lr}                    @ restaur registers */     bx lr                                   @ return  /******************************************************************//*     Converting a register to a decimal                                 */ /******************************************************************//* r0 contains value and r1 address area   */.equ LGZONECAL,   10conversion10:    push {r1-r4,lr}                         @ save registers     mov r3,r1    mov r2,#LGZONECAL1:                                          @ start loop    bl divisionpar10                        @ r0 <- dividende. quotient ->r0 reste -> r1    add r1,#48                              @ digit    strb r1,[r3,r2]                         @ store digit on area    cmp r0,#0                               @ stop if quotient = 0     subne r2,#1                               @ previous position        bne 1b                                  @ else loop                                            @ end replaces digit in front of area    mov r4,#02:    ldrb r1,[r3,r2]     strb r1,[r3,r4]                         @ store in area begin    add r4,#1    add r2,#1                               @ previous position    cmp r2,#LGZONECAL                       @ end    ble 2b                                  @ loop    mov r1,#' '3:    strb r1,[r3,r4]    add r4,#1    cmp r4,#LGZONECAL                       @ end    ble 3b100:    pop {r1-r4,lr}                          @ restaur registres     bx lr                                   @return/***************************************************//*   division par 10   signé                       *//* Thanks to http://thinkingeek.com/arm-assembler-raspberry-pi/*  /* and   http://www.hackersdelight.org/            *//***************************************************//* r0 dividende   *//* r0 quotient *//* r1 remainder  */divisionpar10:  /* r0 contains the argument to be divided by 10 */    push {r2-r4}                           @ save registers  */    mov r4,r0      mov r3,#0x6667                         @ r3 <- magic_number  lower    movt r3,#0x6666                        @ r3 <- magic_number  upper    smull r1, r2, r3, r0                   @ r1 <- Lower32Bits(r1*r0). r2 <- Upper32Bits(r1*r0)     mov r2, r2, ASR #2                     @ r2 <- r2 >> 2    mov r1, r0, LSR #31                    @ r1 <- r0 >> 31    add r0, r2, r1                         @ r0 <- r2 + r1     add r2,r0,r0, lsl #2                   @ r2 <- r0 * 5     sub r1,r4,r2, lsl #1                   @ r1 <- r4 - (r2 * 2)  = r4 - (r0 * 10)    pop {r2-r4}    bx lr                                  @ return `
Output:
```Function time : 0          s 16881      micros
Function time : 0          s 16728      micros
Function time : 0          s 16690      micros
Function time : 0          s 16904      micros
Function time : 0          s 16703      micros
Function time : 0          s 16686      micros
Function time : 0          s 16703      micros
Function time : 0          s 8240       micros
Function time : 0          s 7152       micros
Function time : 0          s 7143       micros
Function time : 0          s 7153       micros
****************************
Function time : 0          s 7153       micros
Function time : 0          s 7143       micros
Function time : 0          s 7153       micros
Function time : 0          s 7151       micros
Function time : 0          s 7151       micros
Function time : 0          s 7144       micros
Function time : 0          s 7153       micros
Function time : 0          s 7177       micros
Function time : 0          s 7143       micros
Function time : 0          s 7156       micros
Function time : 0          s 7154       micros
****************************

```

## Arturo

`func: {	delay 2000} print "Function took: " + [benchmark func] + "s"`
Output:
`Function took: 2001ms`

## AutoHotkey

### System time

Uses system time, not process time

`MsgBox % time("fx")Return fx(){  Sleep, 1000} time(function, parameter=0){  SetBatchLines -1  ; don't sleep for other green threads  StartTime := A_TickCount  %function%(parameter)  Return ElapsedTime := A_TickCount - StartTime . " milliseconds"}`

### Using QueryPerformanceCounter

QueryPerformanceCounter allows even more precision:

`MsgBox, % TimeFunction("fx") TimeFunction(Function, Parameters*) {	SetBatchLines, -1						; SetBatchLines sets the speed of which every new line of coe is run.	DllCall("QueryPerformanceCounter", "Int64*", CounterBefore)	; Start the counter.	DllCall("QueryPerformanceFrequency", "Int64*", Freq)		; Get the frequency of the counter.	%Function%(Parameters*)						; Call the function with it's parameters.	DllCall("QueryPerformanceCounter", "Int64*", CounterAfter)	; End the counter. 	; Calculate the speed of which it counted.	Return, (((CounterAfter - CounterBefore) / Freq) * 1000) . " milliseconds."} fx() {	Sleep, 1000}`

## BaCon

The BaCon TIMER function keeps track of time spent running, in milliseconds (which is also the time unit used by SLEEP). This is not process specific, but a wall clock time counter which starts at 0 during process initialization. As BaCon can easily use external C libraries, process specific CLOCK_PROCESS_CPUTIME_ID clock_gettime could also be used.

`' Time a functionSUB timed()    SLEEP 7000END SUB st = TIMERtimed()et = TIMERPRINT st, ", ", et`
Output:
```prompt\$ ./time-function
0, 7000```

## BASIC

Works with: QBasic
`DIM timestart AS SINGLE, timedone AS SINGLE, timeelapsed AS SINGLE timestart = TIMERSLEEP 1 'code or function to execute goes heretimedone = TIMER 'midnight check:IF timedone < timestart THEN timedone = timedone + 86400timeelapsed = timedone - timestart`

## Batch File

Granularity: hundredths of second.

` @echo offSetlocal EnableDelayedExpansion call :clock ::timed function:fibonacci series.....................................set /a a=0 ,b=1,c=1:loopif %c% lss 2000000000 echo %c% & set /a c=a+b,a=b, b=c & goto loop::.................................................................... call :clock echo  Function executed in %timed% hundredths of secondgoto:eof :clockif not defined timed set timed=0for /F "tokens=1-4 delims=:.," %%a in ("%time%") do ( set /A timed = "(((1%%a - 100) * 60 + (1%%b - 100)) * 60 + (1%%c - 100))  * 100 + (1%%d - 100)- %timed%")goto:eof `

## BBC BASIC

`start%=TIME:REM centi-second timerREM perform processinglapsed%=TIME-start%`

## Bracmat

`( ( time  =   fun funarg t0 ret    .   !arg:(?fun.?funarg)      & clk\$:?t0      & !fun\$!funarg:?ret      & (!ret.flt\$(clk\$+-1*!t0,3) s)  )& ( fib  =    .   !arg:<2&1      | fib\$(!arg+-1)+fib\$(!arg+-2)  )& time\$(fib.30))`

Output:

`1346269.5,141*10E0 s`

## C

Works with: POSIX version .1-2001

On some system (like GNU/Linux) to be able to use the clock_gettime function you must link with the rt (RealTime) library.

`CLOCK_PROCESS_CPUTIME_ID` is preferred when available (eg. Linux kernel 2.6.12 up), being CPU time used by the current process. (`CLOCK_MONOTONIC` generally includes CPU time of unrelated processes, and may be drifted by `adjtime()`.)

`#include <stdio.h>#include <time.h> int identity(int x) { return x; } int sum(int s){  int i;  for(i=0; i < 1000000; i++) s += i;  return s;} #ifdef CLOCK_PROCESS_CPUTIME_ID/* cpu time in the current process */#define CLOCKTYPE  CLOCK_PROCESS_CPUTIME_ID#else/* this one should be appropriate to avoid errors on multiprocessors systems */#define CLOCKTYPE  CLOCK_MONOTONIC#endif double time_it(int (*action)(int), int arg){  struct timespec tsi, tsf;   clock_gettime(CLOCKTYPE, &tsi);  action(arg);  clock_gettime(CLOCKTYPE, &tsf);   double elaps_s = difftime(tsf.tv_sec, tsi.tv_sec);  long elaps_ns = tsf.tv_nsec - tsi.tv_nsec;  return elaps_s + ((double)elaps_ns) / 1.0e9;} int main(){  printf("identity (4) takes %lf s\n", time_it(identity, 4));  printf("sum      (4) takes %lf s\n", time_it(sum, 4));  return 0;}`

## C#

Using Stopwatch.

`using System;using System.Linq;using System.Threading;using System.Diagnostics; class Program {    static void Main(string[] args) {        Stopwatch sw = new Stopwatch();         sw.Start();        DoSomething();        sw.Stop();         Console.WriteLine("DoSomething() took {0}ms.", sw.Elapsed.TotalMilliseconds);    }     static void DoSomething() {        Thread.Sleep(1000);         Enumerable.Range(1, 10000).Where(x => x % 2 == 0).Sum();  // Sum even numers from 1 to 10000    }}`

Using DateTime.

`using System;using System.Linq;using System.Threading; class Program {    static void Main(string[] args) {        DateTime start, end;         start = DateTime.Now;        DoSomething();        end = DateTime.Now;         Console.WriteLine("DoSomething() took " + (end - start).TotalMilliseconds + "ms");    }         static void DoSomething() {        Thread.Sleep(1000);         Enumerable.Range(1, 10000).Where(x => x % 2 == 0).Sum();  // Sum even numers from 1 to 10000    }}`

Output:

```DoSomething() took 1071,5408ms
```

## C++

`#include <ctime>#include <iostream>using namespace std; int identity(int x) { return x; }int sum(int num) {  for (int i = 0; i < 1000000; i++)    num += i;  return num;} double time_it(int (*action)(int), int arg) {  clock_t start_time = clock();  action(arg);  clock_t finis_time = clock();  return ((double) (finis_time - start_time)) / CLOCKS_PER_SEC;} int main() {  cout << "Identity(4) takes " << time_it(identity, 4) << " seconds." << endl;  cout << "Sum(4) takes " << time_it(sum, 4) << " seconds." << endl;  return 0;}`

### Example

```Identity(4) takes 0 seconds.
Sum(4) takes 0.01 seconds.
```

## Clojure

`   (defn fib []    (map first       (iterate         (fn [[a b]] [b (+ a b)])        [0 1])))   (time (take 100 (fib))) `

Output:

```"Elapsed time: 0.028 msecs"
(0 1 1 2 3 5 8 13 21 34 55 89 144 233 377 610 987 1597 2584 4181)
```

## Common Lisp

Common Lisp provides a standard utility for performance measurement, time:

`CL-USER> (time (reduce #'+ (make-list 100000 :initial-element 1)))Evaluation took:  0.151 seconds of real time  0.019035 seconds of user run time  0.01807 seconds of system run time  0 calls to %EVAL  0 page faults and  2,400,256 bytes consed.`

(The example output here is from SBCL.)

However, it merely prints textual information to trace output, so the information is not readily available for further processing (except by parsing it in a CL-implementation-specific manner).

The functions get-internal-run-time and get-internal-real-time may be used to get time information programmatically, with at least one-second granularity (and usually more). Here is a function which uses them to measure the time taken for one execution of a provided function:

`(defun timings (function)  (let ((real-base (get-internal-real-time))        (run-base (get-internal-run-time)))    (funcall function)    (values (/ (- (get-internal-real-time) real-base) internal-time-units-per-second)            (/ (- (get-internal-run-time) run-base) internal-time-units-per-second)))) CL-USER> (timings (lambda () (reduce #'+ (make-list 100000 :initial-element 1))))17/5007/250`

## D

`import std.stdio, std.datetime; int identity(int x) {    return x;} int sum(int num) {    foreach (i; 0 .. 100_000_000)        num += i;    return num;} double timeIt(int function(int) func, int arg) {    StopWatch sw;    sw.start();    func(arg);    sw.stop();    return sw.peek().usecs / 1_000_000.0;} void main() {    writefln("identity(4) takes %f6 seconds.", timeIt(&identity, 4));    writefln("sum(4) takes %f seconds.", timeIt(&sum, 4));}`
Output:
```identity(4) takes 0.0000016 seconds.
sum(4) takes 0.522065 seconds.```

### Using Tango

` import tango.io.Stdout;import tango.time.Clock; int identity (int x){    return x;} int sum (int num){    for (int i = 0; i < 1000000; i++)      num += i;    return num;} double timeIt(int function(int) func, int arg){    long before = Clock.now.ticks;    func(arg);    return (Clock.now.ticks - before) / cast(double)TimeSpan.TicksPerSecond;} void main (){    Stdout.format("Identity(4) takes {:f6} seconds",timeIt(&identity,4)).newline;    Stdout.format("Sum(4) takes {:f6} seconds",timeIt(&sum,4)).newline;} `

## E

Translation of: Java
— E has no standardized facility for CPU time measurement; this
Works with: E-on-Java
.
`def countTo(x) {	println("Counting...")	for _ in 1..x {}	println("Done!")} def MX := <unsafe:java.lang.management.makeManagementFactory>def threadMX := MX.getThreadMXBean()require(threadMX.isCurrentThreadCpuTimeSupported())threadMX.setThreadCpuTimeEnabled(true) for count in [10000, 100000] {	def start := threadMX.getCurrentThreadCpuTime()	countTo(count)	def finish := threadMX.getCurrentThreadCpuTime()	println(`Counting to \$count takes \${(finish-start)//1000000}ms`)}`

## Elena

Translation of: C#

ELENA 4.x :

`import system'calendar;import system'routines;import system'threading;import system'math;import extensions; someProcess(){    threadControl.sleep(1000);     new Range(0,10000).filterBy:(x => x.mod:2 == 0).summarize();} public program(){    var start := now;     someProcess();     var end := now;     console.printLine("Time elapsed in msec:",(end - start).Milliseconds)}`
Output:
```Time elapsed in msec:1015
```

## Elixir

Translation of: Erlang

tc/1

`iex(10)> :timer.tc(fn -> Enum.each(1..100000, fn x -> x*x end) end){236000, :ok}`

tc/2

`iex(11)> :timer.tc(fn x -> Enum.each(1..x, fn y -> y*y end) end, ){2300000, :ok}`

tc/3

`iex(12)> :timer.tc(Enum, :to_list, [1..1000000]){224000, [1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22,  23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41,  42, 43, 44, 45, 46, 47, 48, 49, ...]}`

## Erlang

Erlang's timer module has three implementations of the tc function.

tc/1 takes a 0-arity function and executes it:

` 5> {Time,Result} = timer:tc(fun () -> lists:foreach(fun(X) -> X*X end, lists:seq(1,100000)) end).{226391,ok}6> Time/1000000. % Time is in microseconds.0.2263917> % Time is in microseconds. `

tc/2 takes an n-arity function and its arguments:

` 9> timer:tc(fun (X) -> lists:foreach(fun(Y) -> Y*Y end, lists:seq(1,X)) end, ).{2293844,ok} `

tc/3 takes a module name, function name and the list of arguments to the function:

` 8> timer:tc(lists,seq,[1,1000000]).{62370, [1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,  23,24,25,26,27|...]} `

## Euphoria

`atom tt = time()some_procedure()t = time() - tprintf(1,"Elapsed %f seconds.\n",t)`

## F#

The .Net framework provides a Stopwatch class which provides a performance counter.

` open System.Diagnosticslet myfunc data =    let timer = new Stopwatch()    timer.Start()    let result = data |> expensive_processing    timer.Stop()    printf "elapsed %d ms" timer.ElapsedMilliseconds    result `

## Factor

Works with: Factor version 0.98
`USING: kernel sequences tools.time ; [ 10000 <iota> sum drop ] time`
Output:
```Running time: 0.002888635 seconds

dispatch-stats.  - Print method dispatch statistics
gc-events.       - Print all garbage collection events
gc-stats.        - Print breakdown of different garbage collection events
gc-summary.      - Print aggregate garbage collection statistics
```

## Forth

Works with: GNU Forth
`: time: ( "word" -- )  utime 2>R ' EXECUTE  utime 2R> D-  <# # # # # # # [CHAR] . HOLD #S #> TYPE ."  seconds" ; 1000 time: MS  \ 1.000081 seconds ok`

## Fortran

Works with: Gfortran
version 4.4.5 (Debian 4.4.5-8) on x86_64-linux-gnu
` c The subroutine to analyze      subroutine do_something()c For testing we just do nothing for 3 seconds      call sleep(3)      return      end c Main Program      program timing      integer(kind=8) start,finish,rate      call system_clock(count_rate=rate)      call system_clock(start)         c Here comes the function we want to time      call do_something()      call system_clock(finish)               write(6,*) 'Elapsed Time in seconds:',float(finish-start)/rate      return      end `

## FreeBASIC

`' FB 1.05.0 Win64 Function sumToLimit(limit As UInteger) As UInteger  Dim sum As UInteger = 0  For i As UInteger = 1 To limit    sum += i  Next  Return sumEnd Function Dim As Double start = timerDim limit As UInteger = 100000000Dim result As UInteger = sumToLimit(limit)Dim ms As UInteger = Int(1000 * (timer - start) + 0.5)Print "sumToLimit("; Str(limit); ") = "; resultPrint "took ";  ms; " milliseconds to calculate"PrintPrint "Press any key to quit"Sleep`
Output:
```sumToLimit(100000000) = 5000000050000000
took 314 milliseconds to calculate
```

## GAP

`# Return the time passed in last functiontime;`

## Go

### go test

The Go command line tool `go test` includes benchmarking support. Given a package with functions:

`package empty func Empty() {} func Count() {    // count to a million    for i := 0; i < 1e6; i++ {    }}`

the following code, placed in a file whose name ends in _test.go, will time them:

`package empty import "testing" func BenchmarkEmpty(b *testing.B) {    for i := 0; i < b.N; i++ {        Empty()    }} func BenchmarkCount(b *testing.B) {    for i := 0; i < b.N; i++ {        Count()    }}`

`go test` varies `b.N` to get meaningful resolution. Example:

```\$ go test -bench=.
testing: warning: no tests to run
PASS
BenchmarkEmpty	2000000000	         0.30 ns/op
BenchmarkCount	   10000	    298734 ns/op
ok  		3.642s
```

The first number is the value of `b.N` chosen and the second the average time per iteration. The `testing` package can optionally include memory use and throughput benchmarks.

There is also a standard tool to compare the multiple benchmark outputs (installable via `go get golang.org/x/tools/cmd/benchcmp`).

### testing.Benchmark

The benchmarking features of the `testing` package are exported for use within a Go program.

`package main import (    "fmt"    "testing") func empty() {} func count() {    for i := 0; i < 1e6; i++ {    }} func main() {    e := testing.Benchmark(func(b *testing.B) {        for i := 0; i < b.N; i++ {            empty()        }    })    c := testing.Benchmark(func(b *testing.B) {        for i := 0; i < b.N; i++ {            count()        }    })    fmt.Println("Empty function:    ", e)    fmt.Println("Count to a million:", c)    fmt.Println()    fmt.Printf("Empty: %12.4f\n", float64(e.T.Nanoseconds())/float64(e.N))    fmt.Printf("Count: %12.4f\n", float64(c.T.Nanoseconds())/float64(c.N))}`
Output:
```Empty function:     2000000000	         0.80 ns/op
Count to a million:     2000	    796071 ns/op

Empty:       0.7974
Count:  796071.6555
```

### Alternative technique

The `go test` command and the `testing` package are the preferred techniques for benchmarking or timing any Go code. Ignoring the well-tested and carefully crafted standard tools though, here is a simplistic alternative:

As the first line of the function you wish to time, use defer with an argument of time.Now() to print the elapsed time to the return of any function. For example, define the function from as shown below. It works because defer evaluates its function's arguments at the time the function is deferred, so the current time gets captured at the point of the defer. When the function containing the defer returns, the deferred from function runs, computes the elapsed time as a time.Duration, and prints it with standard formatting, which adds a nicely scaled unit suffix.

`package main import (    "fmt"    "time") func from(t0 time.Time) {    fmt.Println(time.Now().Sub(t0))} func empty() {    defer from(time.Now())} func count() {    defer from(time.Now())    for i := 0; i < 1e6; i++ {    }} func main() {    empty()    count()}`

Output:

```2us
643us
```

## Groovy

Translation of: Java

### CPU Timing

`import java.lang.management.ManagementFactoryimport java.lang.management.ThreadMXBean def threadMX = ManagementFactory.threadMXBeanassert threadMX.currentThreadCpuTimeSupportedthreadMX.threadCpuTimeEnabled = true def clockCpuTime = { Closure c ->    def start = threadMX.currentThreadCpuTime    c.call()    (threadMX.currentThreadCpuTime - start)/1000000}`

### Wall Clock Timing

`def clockRealTime = { Closure c ->    def start = System.currentTimeMillis()    c.call()    System.currentTimeMillis() - start}`

Test:

`def countTo = { Long n ->    long i = 0; while(i < n) { i += 1L }} ["CPU time":clockCpuTime, "wall clock time":clockRealTime].each { measurementType, timer ->    println '\n'    [100000000L, 1000000000L].each { testSize ->        def measuredTime = timer(countTo.curry(testSize))        println "Counting to \${testSize} takes \${measuredTime}ms of \${measurementType}"    }}`

Output:

```Counting to 100000000 takes 23150.5484ms of CPU time
Counting to 1000000000 takes 233861.0991ms of CPU time

Counting to 100000000 takes 24314ms of wall clock time
Counting to 1000000000 takes 249005ms of wall clock time```

## Halon

`\$t = uptime(); sleep(1); echo uptime() - \$t;`

`import System.CPUTime (getCPUTime) -- We assume the function we are timing is an IO monad computationtimeIt :: (Fractional c) => (a -> IO b) -> a -> IO ctimeIt action arg = do  startTime <- getCPUTime  action arg  finishTime <- getCPUTime  return \$ fromIntegral (finishTime - startTime) / 1000000000000 -- Version for use with evaluating regular non-monadic functionstimeIt_ :: (Fractional c) => (a -> b) -> a -> IO ctimeIt_ f = timeIt ((`seq` return ()) . f)`

### Example

```*Main> :m + Text.Printf Data.List
*Main Data.List Text.Printf> timeIt' id 4 >>= printf "Identity(4) takes %f seconds.\n"
Identity(4) takes 0.0 seconds.
*Main Data.List Text.Printf> timeIt' (\x -> foldl' (+) x [1..1000000]) 4 >>= printf "Sum(4) takes %f seconds.\n"
Sum(4) takes 0.248015 seconds.
```

## HicEst

`t_start = TIME()    ! returns seconds since midnightSYSTEM(WAIT = 1234) ! wait 1234 millisecondst_end = TIME() WRITE(StatusBar) t_end - t_start, " seconds"`

## Icon and Unicon

The function 'timef' takes as argument a procedure name and collects performance and timing information including run time (in milliseconds), garbage collection, and memory usage by region.

`procedure timef(f)                               #: time a function flocal gcol,alloc,used,size,runtime,header,x,i title := ["","total","static","string","block"]  # headingscollect()                                        # start with collected memory (before baseline)every put(gcol  := [], -&collections)            # baseline collections countevery put(alloc := [], -&allocated)              # . total allocated space by regionevery put(used  := [], -&storage)                # . currently used space by region - no totalevery put(size  := [], -&regions)                # . current size of regions        - no total write("Performance and Timing measurement for ",image(f),":")  runtime := &time                                 # base time  f()write("Execution time=",&time-runtime," ms.") every (i := 0, x := &collections) do  gcol[i +:= 1] +:= xevery (i := 0, x := &allocated  ) do alloc[i +:= 1] +:= xevery (i := 0, x := &storage    ) do  used[i +:= 1] +:= xevery (i := 0, x := &regions    ) do  size[i +:= 1] +:= x push(gcol,"garbage collections:")push(alloc,"memory allocated:")push(used,"N/A","currently used:")push(size,"N/A","current size:") write("Memory Region and Garbage Collection Summary (delta):")every (i := 0) <:= *!(title|gcol|alloc|used|size)   every x := (title|gcol|alloc|used|size) do {   f := left   every writes(f(!x,i + 3)) do f := right   write()   }write("Note: static region values should be zero and may not be meaningful.")returnend`
Sample usage:
`procedure main()timef(perfectnumbers)end procedure perfectnumbers()...`

Sample output (from the Perfect Numbers task):

```Performance and Timing measurement for procedure perfectnumbers:
Perfect numbers from 1 to 10000:
6
28
496
8128
Done.
Execution time=416 ms.
Memory Region and Garbage Collection Summary (delta):
total                 static                 string                  block
garbage collections:                         2                      0                      0                      2
memory allocated:                      1247012                      0                     24                1246988
currently used:                            N/A                      0                      0                 248040
current size:                              N/A                      0                      0                      0
Note: static region values should be zero and may not be meaningful.
```

## Ioke

`use("benchmark") func = method((1..50000) reduce(+)) Benchmark report(1, 1, func)`

## J

Time and space requirements are tested using verbs obtained through the Foreign conjunction (`!:`). `6!:2` returns time required for execution, in floating-point measurement of seconds. `7!:2` returns a measurement of space required to execute. Both receive as input a sentence for execution. The verb `timespacex` combines these and is available in the standard library.
When the Memoize feature or similar techniques are used, execution time and space can both be affected by prior calculations.

### Example

`   (6!:2 , 7!:2) '|: 50 50 50 \$ i. 50^3'0.00488008 3.14829e6   timespacex '|: 50 50 50 \$ i. 50^3'0.00388519 3.14829e6`

## Janet

`(defmacro time  "Print the time it takes to evaluate body to stderr.\n  Evaluates to body."  [body]  (with-syms [\$start \$val]    ~(let [,\$start (os/clock)           ,\$val ,body]       (eprint (- (os/clock) ,\$start))       ,\$val))) (time (os/sleep 0.5))`
Output:
`0.500129`

## Java

Works with: Java version 1.5+
`import java.lang.management.ManagementFactory;import java.lang.management.ThreadMXBean; public class TimeIt {	public static void main(String[] args) {		final ThreadMXBean threadMX = ManagementFactory.getThreadMXBean();		assert threadMX.isCurrentThreadCpuTimeSupported();		threadMX.setThreadCpuTimeEnabled(true); 		long start, end;		start = threadMX.getCurrentThreadCpuTime();		countTo(100000000);		end = threadMX.getCurrentThreadCpuTime();		System.out.println("Counting to 100000000 takes "+(end-start)/1000000+"ms");		start = threadMX.getCurrentThreadCpuTime();		countTo(1000000000L);		end = threadMX.getCurrentThreadCpuTime();		System.out.println("Counting to 1000000000 takes "+(end-start)/1000000+"ms"); 	} 	public static void countTo(long x){		System.out.println("Counting...");		for(long i=0;i<x;i++);		System.out.println("Done!");	}}`

Measures real time rather than CPU time:

Works with: Java version (all versions)
`	public static void main(String[] args){		long start, end;		start = System.currentTimeMillis();		countTo(100000000);		end = System.currentTimeMillis();		System.out.println("Counting to 100000000 takes "+(end-start)+"ms");		start = System.currentTimeMillis();		countTo(1000000000L);		end = System.currentTimeMillis();		System.out.println("Counting to 1000000000 takes "+(end-start)+"ms"); 	}`

Output:

```Counting...
Done!
Counting to 100000000 takes 370ms
Counting...
Done!
Counting to 1000000000 takes 3391ms
```

## JavaScript

` function test() {    let n = 0    for(let i = 0; i < 1000000; i++){         n += i    }} let start = new Date().valueOf()test()let end = new Date().valueOf() console.log('test() took ' + ((end - start) / 1000) + ' seconds') // test() took 0.001 seconds `

## Julia

`# v0.6.0 function countto(n::Integer)    i = zero(n)    println("Counting...")    while i < n        i += 1    end    println("Done!")end @time countto(10 ^ 5)@time countto(10 ^ 10)`
Output:
```Counting...
Done!
Counting...
Done!
0.000109 seconds (15 allocations: 400 bytes)
Counting...
Done!
0.000127 seconds (15 allocations: 400 bytes)```

## Kotlin

Translation of: Java
`// version 1.1.2// need to enable runtime assertions with JVM -ea option import java.lang.management.ManagementFactoryimport java.lang.management.ThreadMXBean fun countTo(x: Int) {    println("Counting...");    (1..x).forEach {}    println("Done!")} fun main(args: Array<String>) {    val counts = intArrayOf(100_000_000, 1_000_000_000)    val threadMX = ManagementFactory.getThreadMXBean()    assert(threadMX.isCurrentThreadCpuTimeSupported)    threadMX.isThreadCpuTimeEnabled = true     for (count in counts) {        val start = threadMX.currentThreadCpuTime        countTo(count)        val end = threadMX.currentThreadCpuTime        println("Counting to \$count takes \${(end-start)/1000000}ms")    }}`

This is a typical result (sometimes the second figure is only about 1400ms - no idea why)

Output:
```Counting...
Done!
Counting to 100000000 takes 179ms
Counting...
Done!
Counting to 1000000000 takes 3527ms
```

## Lasso

`local(start = micros)loop(100000) => {	'nothing is outout because no autocollect'}'time for 100,000 loop repititions: '+(micros - #start)+' microseconds'`

## Lingo

`on testFunc ()  repeat with i = 1 to 1000000    x = sqrt(log(i))  end repeatend`
`ms = _system.millisecondstestFunc()ms = _system.milliseconds - msput "Execution time in ms:" && ms-- "Execution time in ms: 983"`

## Logo

Works with: UCB Logo
on a Unix system

This is not an ideal method; Logo does not expose a timer (except for the WAIT command) so we use the Unix "date" command to get a second timer.

`to time  output first first shell "|date +%s|endto elapsed :block  localmake "start time  run :block  (print time - :start [seconds elapsed])end elapsed [wait 300]   ; 5 seconds elapsed`

## Lua

`function Test_Function()    for i = 1, 10000000 do        local s = math.log( i )        s = math.sqrt( s )    endend t1 = os.clock()    Test_Function()t2 = os.clock() print( os.difftime( t2, t1 ) )`

## M2000 Interpreter

We use Profiler to reset timer, and Timecount to read time in milliseconds as a double, with nanoseconds for resolution. Internal use of QueryPerformanceCounter from Windows Api. In this example we get times for use of same module with different variable types. sum=limit-limit make sum 0 to the same type of limit,and using n=sum and n++ we make n=1 using same type as sum.

10000% is Integer 16bit

10000& is Long 32bit

[email protected] is Decimal

10000# is Currency

10000~ is Float

10000 is Double (default)

` Module Checkit {      Module sumtolimit (limit) {           sum=limit-limit           n=sum           n++           while limit {sum+=limit*n:limit--:n-!}      }      Cls ' clear screen      Profiler      sumtolimit 10000%      Print TimeCount      Profiler      sumtolimit 10000&      Print TimeCount      Profiler      sumtolimit 10000#      Print TimeCount      Profiler      sumtolimit [email protected]      Print TimeCount      Profiler      sumtolimit 10000~      Print TimeCount      Profiler      sumtolimit 10000      Print TimeCount}Checkit `

## Maple

The built-in command CodeTools:-Usage can compute the "real" time for the length of the computation or the "cpu" time for the computation. The following examples find the real time and cpu time for computing the integer factors for 32!+1.

`CodeTools:-Usage(ifactor(32!+1), output = realtime, quiet);`
`CodeTools:-Usage(ifactor(32!+1), output = cputime, quiet);`

## Mathematica

`AbsoluteTiming[x];`

where x is an operation. Example calculating a million digits of Sqrt:

`AbsoluteTiming[N[Sqrt, 10^6]]`

gives:

`{0.000657, 1.7320508075688772935274463......}`

First elements if the time in seconds, second elements if the result from the operation. Note that I truncated the result.

## Maxima

`f(n) := if n < 2 then n else f(n - 1) + f(n - 2)\$ /* First solution, call the time function with an output line number, it gives the time taken to compute that line.   Here it's assumed to be %o2 */f(24);46368 time(%o2);[0.99] /* Second solution, change a system flag to print timings for all following lines */showtime: true\$ f(24);Evaluation took 0.9400 seconds (0.9400 elapsed)46368`

## MiniScript

`start = timefor i in range(1,100000)end forduration = time - startprint "Process took " + duration + " seconds"`
Output:
```Process took 0.312109 seconds
```

## Nim

`import times, os proc doWork(x) =  var n = x  for i in 0..10000000:    n += i  echo n template time(s: stmt): expr =  let t0 = cpuTime()  s  cpuTime() - t0 echo time(doWork(100))`

Output:

`2.2000000000000000e-01`

## OCaml

`let time_it action arg =  let start_time = Sys.time () in  ignore (action arg);  let finish_time = Sys.time () in  finish_time -. start_time`

### Example

```# Printf.printf "Identity(4) takes %f seconds.\n" (time_it (fun x -> x) 4);;
Identity(4) takes 0.000000 seconds.
- : unit = ()
# let sum x = let num = ref x in for i = 0 to 999999 do num := !num + i done; !num;;
val sum : int -> int = <fun>
# Printf.printf "Sum(4) takes %f seconds.\n" (time_it sum 4);;
Sum(4) takes 0.084005 seconds.
- : unit = ()
```

## Oforth

bench allows to calculate how long a runnable takes to execute.

Result is microseconds.

It uses difference between system time, not processing time.

Output:
```>#[ 0 1000 seq apply(#+) ] bench .
267
500500 ok
```

## Oz

`declare  %% returns milliseconds  fun {TimeIt Proc}     Before = {Now}  in     {Proc}     {Now} - Before  end   fun {Now}     {Property.get 'time.total'}  endin  {Show   {TimeIt    proc {\$}       {FoldL {List.number 1 1000000 1} Number.'+' 4 _}    end}  }`

## PARI/GP

This version, by default, returns just the CPU time used by gp, not the delta of wall times. PARI can be compiled to use wall time if you prefer: configure with `--time=ftime` instead of ```--time= getrusage```, `--time=clock_gettime`, or `--time=times`. See Appendix A, section 2.2 of the User's Guide to PARI/GP.

`time(foo)={  foo();  gettime();}`

Alternate version:

Works with: PARI/GP version 2.6.2+
`time(foo)={  my(start=getabstime());  foo();  getabstime()-start;}`

## Perl

Example of using the built-in Benchmark core module - it compares two versions of recursive factorial functions:

`use Benchmark;use Memoize; sub fac1 {    my \$n = shift;    return \$n == 0 ? 1 : \$n * fac1(\$n - 1);}sub fac2 {    my \$n = shift;    return \$n == 0 ? 1 : \$n * fac2(\$n - 1);}memoize('fac2'); my \$result = timethese(100000, {    'fac1' => sub { fac1(50) },    'fac2' => sub { fac2(50) },});Benchmark::cmpthese(\$result);`

Output:

```Benchmark: timing 100000 iterations of fac1, fac2...
fac1:  6 wallclock secs ( 5.45 usr +  0.00 sys =  5.45 CPU) @ 18348.62/s (n=100000)
fac2:  1 wallclock secs ( 0.84 usr +  0.00 sys =  0.84 CPU) @ 119047.62/s (n=100000)
Rate fac1 fac2
fac1  18349/s   -- -85%
fac2 119048/s 549%   --
```

Example without using Benchmark:

`sub cpu_time {  my (\$user,\$system,\$cuser,\$csystem) = times;  \$user + \$system} sub time_it {  my \$action = shift;  my \$startTime = cpu_time();  \$action->(@_);  my \$finishTime = cpu_time();  \$finishTime - \$startTime} printf "Identity(4) takes %f seconds.\n", time_it(sub {@_}, 4);# outputs "Identity(4) takes 0.000000 seconds." sub sum {  my \$x = shift;  foreach (0 .. 999999) {    \$x += \$_;  }  \$x} printf "Sum(4) takes %f seconds.\n", time_it(\&sum, 4);# outputs "Sum(4) takes 0.280000 seconds."`

## Phix

Measures wall-clock time. On Windows the resolution is about 15ms. The elapsed function makes things more human-readable, eg 720 (seconds) => 12 minutes

`atom t0 = time()some_procedure()printf(1,"%3.2fs\n",time()-t0)printf(1,"%s\n",{elapsed(time()-t0)})`

## Phixmonti

`def count	for drop endforenddef 1000000 countmsec dup var t0 print " seconds" print nl 10000000 countmsec t0 - print " seconds" print`

## PicoLisp

There is a built-in function 'bench' for that. However, it measures wall-clock time, because for practical purposes the real time needed by a task (including I/O and communication) is more meaningful. There is another function, 'tick', which also measures user time, and is used by the profiling tools.

`: (bench (do 1000000 (* 3 4)))0.080 sec-> 12`

## Pike

Shows CPU time used, not including any automatic gc passes. Explicit calls to gc() are included though. This example uses the convenience function gauge(), but it could also be done manually with gethrvtime() in ms or ns resolution.

` void get_some_primes(){    int i;    while(i < 10000)        i = i->next_prime();} void main(){    float time_wasted = gauge( get_some_primes() );    write("Wasted %f CPU seconds calculating primes\n", time_wasted);} `
Output:
```Wasted 0.014 CPU seconds calculating primes
```

## PL/I

`declare (start_time, finish_time) float (18); start_time = secs(); do i = 1 to 10000000;   /* something to be repeated goes here. */end;finish_time = secs(); put skip edit ('elapsed time=', finish_time - start_time, ' seconds')   (A, F(10,3), A);   /* gives the result to thousandths of a second. */ /* Note: using the SECS function takes into account the clock *//* going past midnight. */`

## PowerShell

` function fun(\$n){    \$res = 0    if(\$n -gt 0) {        1..\$n | foreach{            \$a, \$b = \$_, (\$n+\$_)            \$res += \$a + \$b        }     }    \$res   }"\$((Measure-Command {fun 10000}).TotalSeconds) Seconds" `

Output:

```0.820712 Seconds
```

## PureBasic

### Built in timer

This version uses the built in timer, on Windows it has an accuracy of ~10-15 msec.

`Procedure Foo(Limit)  Protected i, palindromic, String\$  For i=0 To Limit    String\$=Str(i)    If String\$=ReverseString(String\$)      palindromic+1    EndIf  Next  ProcedureReturn palindromicEndProcedure If OpenConsole()  Define Start, Stop, cnt  PrintN("Starting timing of a calculation,")  PrintN("for this we test how many of 0-1000000 are palindromic.")  Start=ElapsedMilliseconds()  cnt=Foo(1000000)  Stop=ElapsedMilliseconds()  PrintN("The function need "+Str(stop-Start)+" msec,")  PrintN("and "+Str(cnt)+" are palindromic.")  Print("Press ENTER to exit."): Input()EndIf`
```Starting timing of a calculation,
for this we test how many of 0-1000000 are palindromic.
The function need 577 msec,
and 1999 are palindromic.
Press ENTER to exit.
```

### Hi-res version

Library: Droopy

This version uses a hi-res timer, but it is Windows only.

`If OpenConsole()  Define Timed.f, cnt  PrintN("Starting timing of a calculation,")  PrintN("for this we test how many of 0-1000000 are palindromic.")  ; Dependent on Droopy-library  If MeasureHiResIntervalStart()    ; Same Foo() as above...    cnt=Foo(1000000)    Timed=MeasureHiResIntervalStop()  EndIf  PrintN("The function need "+StrF(Timed*1000,3)+" msec,")  PrintN("and "+Str(cnt)+" are palindromic.")  Print("Press ENTER to exit."): Input()EndIf`
```Starting timing of a calculation,
for this we test how many of 0-1000000 are palindromic.
The function need 604.341 msec,
and 1999 are palindromic.
Press ENTER to exit.
```

This version still relies on the Windows API but does not make use of any additional libraries.

`Procedure.f ticksHQ(reportIfPresent = #False)  Static maxfreq.q   Protected T.q   If reportIfPresent Or maxfreq = 0     QueryPerformanceFrequency_(@maxfreq)     If maxfreq      ProcedureReturn 1.0    Else      ProcedureReturn 0    EndIf   EndIf   QueryPerformanceCounter_(@T)   ProcedureReturn T / maxfreq ;Result is in millisecondsEndProcedure  If OpenConsole()  Define timed.f, cnt  PrintN("Starting timing of a calculation,")  PrintN("for this we test how many of 0-1000000 are palindromic.")  ; Dependent on Windows API  If ticksHQ(#True)    timed = ticksHQ() ;start time    ; Same Foo() as above...    cnt = Foo(1000000)    timed = ticksHQ() - timed ;difference  EndIf  PrintN("The function need " + StrF(timed * 1000, 3) + " msec,")  PrintN("and " + Str(cnt) + " are palindromic.")  Print("Press ENTER to exit."): Input()EndIf`

Sample output:

```Starting timing of a calculation,
for this we test how many of 0-1000000 are palindromic.
The function need 174.811 msec,
and 1999 are palindromic.
```

## Python

Given function and arguments return a time (in microseconds) it takes to make the call.

Note: There is an overhead in executing a function that does nothing.

`import sys, timeitdef usec(function, arguments):    modname, funcname = __name__, function.__name__    timer = timeit.Timer(stmt='%(funcname)s(*args)' % vars(),                         setup='from %(modname)s import %(funcname)s; args=%(arguments)r' % vars())    try:        t, N = 0, 1        while t < 0.2:                        t = min(timer.repeat(repeat=3, number=N))                        N *= 10        microseconds = round(10000000 * t / N, 1) # per loop        return microseconds     except:        timer.print_exc(file=sys.stderr)        raise from math import powdef nothing(): passdef identity(x): return x`

### Example

```>>> print(usec(nothing, []))
1.7
>>> print(usec(identity, ))
2.2
>>> print(usec(pow, (2, 100)))
3.3
>>> print([usec(qsort, (range(n),)) for n in range(10)])
[2.7, 2.8, 31.4, 38.1, 58.0, 76.2, 100.5, 130.0, 149.3, 180.0]
```

using qsort() from Quicksort. Timings show that the implementation of qsort() has quadratic dependence on sequence length N for already sorted sequences (instead of O(N*log(N)) in average).

## R

R has a built-in function, system.time, to calculate this.

`# A taskfoo <- function(){   for(i in 1:10)   {      mat <- matrix(rnorm(1e6), nrow=1e3)      mat^-0.5   }}# Time the tasktimer <- system.time(foo())# Extract the processing timetimer["user.self"]`

For a breakdown of processing time by function, there is Rprof.

`Rprof()foo()Rprof(NULL)summaryRprof()`

## Racket

` #lang racket(define (fact n) (if (zero? n) 1 (* n (fact (sub1 n)))))(time (fact 5000)) `

## Raku

(formerly Perl 6) Follows modern trend toward measuring wall-clock time, since CPU time is becoming rather ill-defined in the age of multicore, and doesn't reflect IO overhead in any case.

`my \$start = now;(^100000).pick(1000);say now - \$start;`
Output:
`0.02301709`

## Raven

`define doId use \$x   \$x dup * \$x / define doPower use \$v, \$p   \$v \$p pow define doSort   group      20000 each choose   list sort reverse define timeFunc use \$fName   time as \$t1   \$fName "" prefer call   time as \$t2   \$fName \$t2 \$t1 -"%.4g secs for %s\n" print "NULL" timeFunc42 "doId" timeFunc12 2 "doPower" timeFunc"doSort" timeFunc`
Output:
```2.193e-05 secs for NULL
2.003e-05 secs for doId
4.601e-05 secs for doPower
3.028 secs for doSort```

## Retro

Retro has a time function returning the current time in seconds. This can be used to build a simple timing function:

`: .runtime ( a- ) time [ do time ] dip - "\n%d\n" puts ; : test 20000 [ putn space ] iterd ;&test .runtime`

Finer measurements are not possible with the standard implementation.

## REXX

### elapsed time version

REXX doesn't have a language feature for obtaining true CPU time (except under
IBM mainframes which have commands that can retrieve such times), but it does
have a built-in function for elapsed time(s).

The main reason for the true CPU time omission is that REXX was developed under VM/CMS and
there's a way to easily query the host (VM/CP) to indicate how much   true   CPU time was used by
(normally) your own userID.  The result can then be placed into a REXX variable (as an option).

`/*REXX program displays the elapsed time for a REXX function (or subroutine). */arg reps .                             /*obtain an optional argument from C.L.*/if reps==''  then reps=100000          /*Not specified?  No, then use default.*/call time 'Reset'                      /*only the 1st character is examined.  */junk = silly(reps)                     /*invoke the  SILLY  function (below). */                                       /*───►   CALL SILLY REPS    also works.*/              /*                          The    E   is for    elapsed    time.*/             /*                                 │             ─               */             /*                        ┌────◄───┘                             */             /*                        │                                      */             /*                        ↓                                      */say 'function SILLY took' format(time("E"),,2)  'seconds for' reps "iterations."             /*                             ↑                                 */             /*                             │                                 */             /*            ┌────────►───────┘                                 */             /*            │                                                  */             /* The above  2  for the  FORMAT  function displays the time with*/             /* two decimal digits (rounded)  past the decimal point).  Using */             /* a   0  (zero)    would round the  time  to whole seconds.     */exit                                   /*stick a fork in it,  we're all done. *//*────────────────────────────────────────────────────────────────────────────*/silly: procedure               /*chew up some CPU time doing some silly stuff.*/            do j=1  for arg(1) /*wash,  apply,  lather,  rinse,  repeat.  ··· */            @.j=random() date() time() digits() fuzz() form() xrange() queued()            end   /*j*/ return j-1`

output   when using a personal computer built in the 20th century:

```function SILLY took 3.54 seconds for 100000 iterations.
```

output   when using a personal computer built in the 21st century:

```function SILLY took 0.44 seconds for 100000 iterations.
```

output   when using an IBM mainframe with MVS/TSO:

```function SILLY took 0.69 seconds for 100000 iterations.
```

### CPU time used version

This version   only   works with Regina REXX as the   J   option   (for the time BIF)   is a Regina extension.

Since the   silly   function (by far) consumes the bulk of the CPU time of the REXX program, what is
being measured is essentially the same as the wall clock time (duration) of the function execution;   the
overhead of the invocation is minimal compared to the overall time used.

`/*REXX program displays the elapsed time for a REXX function (or subroutine). */arg reps .                             /*obtain an optional argument from C.L.*/if reps==''  then reps=100000          /*Not specified?  No, then use default.*/call time 'Reset'                      /*only the 1st character is examined.  */junk = silly(reps)                     /*invoke the  SILLY  function (below). */                                       /*───►   CALL SILLY REPS    also works.*/              /*                          The   J   is for the CPU time used   */             /*                                │   by the REXX program since  */             /*                        ┌───────┘   since the time was  RESET. */             /*                        │           This is a Regina extension.*/             /*                        ↓                                      */say 'function SILLY took' format(time("J"),,2)  'seconds for' reps "iterations."             /*                             ↑                                 */             /*                             │                                 */             /*            ┌────────►───────┘                                 */             /*            │                                                  */             /* The above  2  for the  FORMAT  function displays the time with*/             /* two decimal digits (rounded)  past the decimal point).  Using */             /* a   0  (zero)    would round the  time  to whole seconds.     */exit                                   /*stick a fork in it,  we're all done. *//*────────────────────────────────────────────────────────────────────────────*/silly: procedure               /*chew up some CPU time doing some silly stuff.*/            do j=1  for arg(1) /*wash,  apply,  lather,  rinse,  repeat.  ··· */            @.j=random() date() time() digits() fuzz() form() xrange() queued()            end   /*j*/ return j-1`

output   is essentially identical to the previous examples.

## Ring

` beginTime = TimeList()for n = 1 to 10000000    n = n + 1nextendTime = TimeList()elapsedTime = endTime - beginTimesee "Elapsed time = " + elapsedTime + nl `

## Ruby

Ruby's Benchmark module provides a way to generate nice reports (numbers are in seconds):

`require 'benchmark' Benchmark.bm(8) do |x|  x.report("nothing:")  {  }  x.report("sum:")  { (1..1_000_000).inject(4) {|sum, x| sum + x} }end`

Output:

```              user     system      total        real
nothing:  0.000000   0.000000   0.000000 (  0.000014)
sum:      2.700000   0.400000   3.100000 (  3.258348)
```

You can get the total time as a number for later processing like this:

`Benchmark.measure { whatever }.total`

## Scala

Define a `time` function that returns the elapsed time (in ms) to execute a block of code.

` def time(f: => Unit)={	val s = System.currentTimeMillis	f	System.currentTimeMillis - s} `

Can be called with a code block:

` println(time {	for(i <- 1 to 10000000) {}}) `

Or with a function:

` def count(i:Int) = for(j <- 1 to i){} println(time (count(10000000))) `

## Scheme

`(time (some-function))`

## Seed7

`\$ include "seed7_05.s7i";  include "time.s7i";  include "duration.s7i"; const func integer: identity (in integer: x) is  return x; const func integer: sum (in integer: num) is func  result    var integer: result is 0;  local    var integer: number is 0;  begin    result := num;    for number range 1 to 1000000 do      result +:= number;    end for;  end func; const func duration: timeIt (ref func integer: aFunction) is func  result    var duration: result is duration.value;  local    var time: before is time.value;  begin    before := time(NOW);    ignore(aFunction);    result := time(NOW) - before;  end func; const proc: main is func  begin    writeln("Identity(4) takes " <& timeIt(identity(4)));    writeln("Sum(4)      takes " <& timeIt(sum(4)));  end func;`
Output:
of interpreted program:
```Identity(4) takes 0-00-00 00:00:00.000163
Sum(4)      takes 0-00-00 00:00:00.131823
```
Output:
of compiled program (optimized with -O2):
```Identity(4) takes 0-00-00 00:00:00.000072
Sum(4)      takes 0-00-00 00:00:00.000857
```

## Sidef

`var benchmark = frequire('Benchmark') func fac_rec(n) {    n == 0 ? 1 : (n * __FUNC__(n - 1))} func fac_iter(n) {    var prod = 1    n.times { |i|        prod *= i    }    prod} var result = benchmark.timethese(-3, Hash(    'fac_rec'  => { fac_rec(20)  },    'fac_iter' => { fac_iter(20) },)) benchmark.cmpthese(result)`
Output:
```Benchmark: running fac_iter, fac_rec for at least 3 CPU seconds...
fac_iter:  3 wallclock secs ( 3.23 usr +  0.00 sys =  3.23 CPU) @ 7331.89/s (n=23682)
fac_rec:  3 wallclock secs ( 3.19 usr +  0.00 sys =  3.19 CPU) @ 3551.72/s (n=11330)
Rate  fac_rec fac_iter
fac_rec  3552/s       --     -52%
fac_iter 7332/s     106%       --
```

## Slate

` [inform: 2000 factorial] timeToRun. `

## Smalltalk

(Squeak/Pharo)

` Time millisecondsToRun: [ 	Transcript show: 2000 factorial ]. `

## Standard ML

`fun time_it (action, arg) = let  val timer = Timer.startCPUTimer ()  val _ = action arg  val times = Timer.checkCPUTimer timerin  Time.+ (#usr times, #sys times)end`

### Example

```- print ("Identity(4) takes " ^ Time.toString (time_it (fn x => x, 4)) ^ " seconds.\n");
Identity(4) takes 0.000 seconds.
val it = () : unit
- fun sum (x:IntInf.int) = let
fun loop (i, sum) =
if i >= 1000000 then sum
else loop (i + 1, sum + i)
in loop (0, x)
end;
val sum = fn : IntInf.int -> IntInf.int
- print ("Sum(4) takes " ^ Time.toString (time_it (sum, 4)) ^ " seconds.\n");
Sum(4) takes 0.220 seconds.
val it = () : unit
```

## Stata

Stata can track up to 100 timers. See timer in Stata help.

`program timer_test	timer clear 1	timer on 1	sleep `0'	timer off 1	timer list 1end . timer_test 1000   1:      1.01 /        1 =       1.0140`

## Swift

Using the 2-term ackermann function for demonstration.

`import Foundation public struct TimeResult {  public var seconds: Double  public var nanoSeconds: Double   public var duration: Double { seconds + (nanoSeconds / 1e9) }   @usableFromInline  init(seconds: Double, nanoSeconds: Double) {    self.seconds = seconds    self.nanoSeconds = nanoSeconds  }} extension TimeResult: CustomStringConvertible {  public var description: String {    return "TimeResult(seconds: \(seconds); nanoSeconds: \(nanoSeconds); duration: \(duration)s)"  }} public struct ClockTimer {  @inlinable @inline(__always)  public static func time<T>(_ f: () throws -> T) rethrows -> (T, TimeResult) {    var tsi = timespec()    var tsf = timespec()     clock_gettime(CLOCK_MONOTONIC_RAW, &tsi)    let res = try f()    clock_gettime(CLOCK_MONOTONIC_RAW, &tsf)     let secondsElapsed = difftime(tsf.tv_sec, tsi.tv_sec)    let nanoSecondsElapsed = Double(tsf.tv_nsec - tsi.tv_nsec)     return (res, TimeResult(seconds: secondsElapsed, nanoSeconds: nanoSecondsElapsed))  }} func ackermann(m: Int, n: Int) -> Int {  switch (m, n) {  case (0, _):    return n + 1  case (_, 0):    return ackermann(m: m - 1, n: 1)  case (_, _):    return ackermann(m: m - 1, n: ackermann(m: m, n: n - 1))  }} let (n, t) = ClockTimer.time { ackermann(m: 3, n: 11) } print("Took \(t.duration)s to calculate ackermann(m: 3, n: 11) = \(n)") let (n2, t2) = ClockTimer.time { ackermann(m: 4, n: 1) } print("Took \(t2.duration)s to calculate ackermann(m: 4, n: 1) = \(n2)")`
Output:
```Took 0.193593682s to calculate ackermann(m: 3, n: 11) = 16381
Took 3.103710995s to calculate ackermann(m: 4, n: 1) = 65533```

## Tcl

The Tcl `time` command returns the real time elapsed averaged over a number of iterations.

`proc sum_n {n} {    for {set i 1; set sum 0.0} {\$i <= \$n} {incr i} {set sum [expr {\$sum + \$i}]}    return [expr {wide(\$sum)}]} puts [time {sum_n 1e6} 100]puts [time {} 100]`
Output:
```163551.0 microseconds per iteration
0.2 microseconds per iteration
```

## TorqueScript

Greek2me 02:16, 19 June 2012 (UTC)

Returns average time elapsed from many iterations.

` function benchmark(%times,%function,%a,%b,%c,%d,%e,%f,%g,%h,%i,%j,%k,%l,%m,%n,%o){	if(!isFunction(%function))	{		warn("BENCHMARKING RESULT FOR" SPC %function @ ":" NL "Function does not exist.");		return -1;	} 	%start = getRealTime(); 	for(%i=0; %i < %times; %i++)	{		call(%function,%a,%b,%c,%d,%e,%f,%g,%h,%i,%j,%k,%l,%m,%n,%o);	} 	%end = getRealTime(); 	%result = (%end-%start) / %times; 	warn("BENCHMARKING RESULT FOR" SPC %function @ ":" NL %result); 	return %result;} `
Example:
` function exampleFunction(%var1,%var2){	//put stuff here} benchmark(500,"exampleFunction","blah","variables"); ==> BENCHMARKING RESULT FOR exampleFunction:==> 13.257 `

## TUSCRIPT

` \$\$ MODE TUSCRIPTSECTION testLOOP n=1,999999rest=MOD (n,1000)IF (rest==0) Print nENDLOOPENDSECTIONtime_beg=TIME ()DO testtime_end=TIME ()interval=TIME_INTERVAL (seconds,time_beg,time_end)PRINT "'test' start at ",time_begPRINT "'test' ends  at ",time_endPRINT "'test' takes ",interval," seconds" `
Output:
```'test' start at 2011-01-15 14:38:22
'test' ends  at 2011-01-15 14:38:31
'test' takes 9 seconds
```

## UNIX Shell

`\$ time sleep 1`
```real    0m1.074s
user    0m0.001s
sys     0m0.006s
```

## VBA

`Public Declare Function GetTickCount Lib "kernel32.dll" () As LongPrivate Function identity(x As Long) As Long    For j = 0 To 1000    identity = x    Next jEnd FunctionPrivate Function sum(ByVal num As Long) As Long    Dim t As Long    For j = 0 To 1000    t = num    For i = 0 To 10000        t = t + i    Next i    Next j    sum = tEnd FunctionPrivate Sub time_it()    Dim start_time As Long, finis_time As Long    start_time = GetTickCount    identity 1    finis_time = GetTickCount    Debug.Print "1000 times Identity(1) takes "; (finis_time - start_time); " milliseconds"    start_time = GetTickCount    sum 1    finis_time = GetTickCount    Debug.Print "1000 times Sum(1) takes "; (finis_time - start_time); " milliseconds"End Sub`
Output:
```1000 times Identity(1) takes  0  seconds
1000 times Sum(1) takes  296  seconds```

## Wart

`time 1+130000/1000000  # in microseconds=> 2`

## Wren

The only way Wren currently has to time a function is to measure the System time before and after the function is called. We therefore use that approach, averaging over say 100 runs, having first shut down as many other processes as we can.

`var f = Fn.new {    for (i in 0..1e7) {}} var runs = 100var total = 0for (i in 1..runs) {    var start = System.clock    f.call()    total = total + System.clock - start}System.print("Over %(runs) runs, took an average of %(total/runs) seconds.")`
Output:
```Over 100 runs, took an average of 0.19607459 seconds.
```

## XPL0

This works fine under pure DOS but has problems under Windows. Windows can execute other processes, although it could be argued that this should be included as part of the total time to accomplish the task at hand. DOS does go off to service a timer interrupt, but it's usually very fast, although beware of TSRs that hook this interrupt handler.

There's a more serious problem with the GetTime intrinsic under Windows XP. GetTime provides microsecond resolution by combining the BIOS timer interrupt count at location 046C with the count in the 8254 chip (or its equivalent). Unfortunately, Windows virtualizes the 8254 and thus the two values can be out of sync.

`include c:\cxpl\codes;int T0, T1, I;[T0:= GetTime;for I:= 1, 1_000_000 do [];T1:= GetTime;IntOut(0, T1-T0); Text(0, " microseconds^M^J");]`
Example output:
for a Duron 850 running DOS 5.0:
```2354 microseconds
```

## Yabasic

`sub count(n)	local i 	for i = 1 to n	next iend sub count(1000000) print peek("millisrunning"), " milliseconds" t0 = peek("millisrunning")count(10000000)print peek("millisrunning")-t0, " milliseconds"`

## zkl

In order to be as OS independent as possible, only system time is available.

`t:=Time.Clock.time; Atomic.sleep(3); (Time.Clock.time - t).println();`
Output:
`3`