Hello! In my library, Fig ( GitHub - AnonMiraj/fig: FIG (Fortran Intuitive Graphics) ), I often need to compare different, similar approaches for their efficiency in terms of time and possibly space. I was thinking of using a bash script to compare the time between two programs, but I wonder if th…

There are several fpm packages available. You might want to try ForTime: GitHub - gha3mi/fortime: ForTime - A Fortran library for measuring elapsed time, DATE_AND_TIME time, CPU time, OMP time and MPI time. Here’s how to use it simply: use fortime type(timer) :: t call t%timer_start() ! Your code…

It depends if you are interested in comparing elapsed times or cpu times. Look up the intrinsic procedures cpu_time() and system_clock().

[image] How to show the true wall time instead of cpu_time? A few years ago, I compared time measurement subroutines in Fortran. I recommend date_and_time or omp_get_wtime (OpenMP’s time measurement function) as time measurement subroutines. For system_clock, the count r…

thank you this is exactly what i am looking for

I wrote many moons ago a simple module for timings. https://bazaar.launchpad.net/~hwkrus/dolfyn-cfd/trunk/view/head:/src/watches.f90 At the end of the run it displays how much time was spent where (either the whole subroutine, or a loop or a call). An example: Elapsed time: 35861.20 W L…

@hkvzjal I would recommend you look to other threads, as of the timing routines mentioned in this thread, system_clock is probably the best routine available. You need to test the different integer kind arguments, as this can vary the accuracy and range. Using 8-byte integers in Gfortran gives a …

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hkvzjal April 20, 2024, 7:32pm 3

You might find this thread very insightful for a comparison of several methods to measure elapsed time.

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