You may use TIC and TOC command in matlab to measure time...

Strange, since toc is supposed to be in seconds. Can you provide a minimum example code, i.e. at least the time measuring code you were using?

Few possibilities:

Do you have multiple tics and tocs in your code?

Did you encompass the whole code in a tic-toc block?

The time is in second.

I think you probably misplace the "tic" ?

It should be even before the matrix or vector creation (which could take time if they are big).

>> M=zeros(10000); tic ; for i=1:100000000 ; end ; toc

Elapsed time is 0.524525 seconds.

>> tic; M=zeros(10000) ; for i=1:100000000 ; end ; toc

Elapsed time is 1.135308 seconds.

Regards

Dear Aarti;

The differences between these two methods is because, tic and toc ignores some processes and centralized only in the time spent executing the code.

Regards

David

An other remark to complete this problem of time measurement.

Tic, toc, clock, and other Matlab commands are using the internal clock of the computer.

If you are using Windows, the OS is using by default a software clock which is periodically synchronized through the internet. A problem (and this has been my problem...) can occur if you computer is not connected to the internet during the time measurement: in that case, you will obtain an impressive time shift. For example in our application, this time shift has been evaluated to a quarter of hour for each our!

The solution in that case is to oblige the OS to use its internal RTC (Real Time Clock). The procedure can be found on the Internet.

To determine a real execution time the computer spends on running functions in MATLAB use profile function:

profile on

... your code ...

profile viewer   % to stop the profiler and get the profile report

This function counts execution time spent on each row of the code between "profile on" and "profile viewer" as well as the number of function calls, parent and child functions, etc.:

http://www.mathworks.com/help/matlab/ref/profile.html

The profile tool will not provide the real execution time of the code because the profiler itself adds significant overhead.

I believe other responders are correct that tic and toc measure CPU time rather than wall clock time; it sounds like either they are misplaced or there is something else significantly impacting the timing.  There are a lot of possibilities for what this could be; if you haven't done so already I would suggest running the test several times to see if the disparity is consistent.

Thank you everyone for your answer.

I used:

z =clock;

%my code

etime(clock, z)

And I could get the correct time.

You may use TIC and TOC command in matlab to measure time...

In matlab Elapsed CPU time function is there please try Hope it is use full 

see the following link:

http://www.mathworks.co.uk/help/matlab/ref/cputime.html

Dear Gehani,

Good Day

at the start of our *.m file just type( tic ) and the end type (toc) as follow:

tic

.......

..........

toc

You will see the result on the main MATLAB window after the execution of the *.m file

You can write TIC and TOC commands not only at the beginning of your m-file but at the beginning and at the end of any part of your code you want to check, e.g. function, part of function, etc.

just type help toc, you will find an examples such as 

Measure the minimum and average time to compute a sum

of Bessel functions.

REPS = 1000; minTime = Inf; nsum = 10;

tic;

for i=1:REPS

tstart = tic;

sum = 0; for j=1:nsum, sum = sum + besselj(j,REPS); end

telapsed = toc(tstart);

minTime = min(telapsed,minTime);

end

averageTime = toc/REPS;

Good Luck

Tic and Toc are brilliant for measuring the time of all or part of your Matlab programme in seconds.

StartTimeVariable = tic;

StopTimeVariable = toc;

TotalTimeVariable = StopTimeVariable - StartTimeVariable

The variables can be (almost) anything.  If you want it to give you the start/stop/total times in the command line box then don't put a semi-colon at the end.  If you're putting it into a results file then you may want to have a semi-colon at the end so that you don't get it in the command line box. 

tic and toc are useful, but creating a full profile may be of more use in terms of shining some light on the process which take the longest to complete. 

http://www.mathworks.co.uk/help/matlab/ref/profile.html

Clearly you know if 0.7283 s or 27 s was correct!

Just a quick comment: If your time is small then it is a good idea to measure it several times and take an average and a look at the disctubution too, as the time will be affected by several things, including what is in the cache, wnat is not, etc.

Hello,

tic

----- your MATLAB program -----

toc

Time=toc/60    (: to show the time in minutes)

Good luck,

Morteza Shabanzadeh

http://mortezash.blogfa.com/

Dear Colleagues,

 I have a problem in obtaining the CPU time by using the TIC and TOC or profile viewer commands.

If I use these functions, I get the CPU time of my code, but the problem is that if I run my code twice or more, the resulted CPU time for every run is different.

for example:

first run of the code: .01112

second run of the same code: 0.1234

third run of the same code: 0.1025

...

Any comment on finding the exact time is appreciated.

Dear Mrfa,

You can put your code in between

z = clock;

.....

etime(clock, z)

The unit to time taken will be seconds

Tic and Toc work. There are several reasons why when you do it more than once the times change. Amongst those I can mention these 2: (I) The first time you run the code will not be in the cache of the CPU, therefore it will probably take longer to run; (ii) your code is NOT the only thing running on your computer as here are several housekeeping tasks competing for time using interrupts. If you are interrupted by one or more of these it will take you a little longer.

I always used tic toc.

I experienced the same problem too. So, what is the way out?

Hi

I always use this way

t = cputime;

Your code

e = cputime-t

and e will have the time in seconds

I found tic and toc most handy

tic toc are quite informative and easy to use

Tic TOC is quite easy and solves the problem

tic

yourCode

timeElapsed = toc

Hello,

I've tried tic toc as well etime(clock,z) however when repeated the execution it gaves different value every time! can any one explain and propose a more efficient method? Thanks

Hello Aarti,

I am not sure if this is late. I am new to MATLAB and had questions about the tic toc function too initially. To the best of my knowledge, if you initialize tic at the beginning of your code and close with a toc, you will usually get something like "Elapsed time is 78.426065 seconds." So, you see the tic toc function returns time in seconds. If you will find the following useful, I considered the very long time it takes most of my codes to run and simply did this:

function myTimer

timeElapsed = toc;

timeElapsed_min = toc/60;

timeElapsed_hr = toc/3600;

if (timeElapsed = 60) && (timeElapsed

Hi

tic & toc are usually used in measuring the run time of the code