[flint-devel] Timing code

[Richard Howell-P. <ric...@gm...>]

ok, I will look into that. Before I read your reply I wrote this code which
just does timings in Flint, then I was going to do some magma timings and do
the graph in Excel. I guess proper timings are important officially for the
project but if this way is quicker then I'd do it instead so I can get
something on my poster. Is this a reasonable way to time the factorisation
function? It seems to work for me but I'm not sure I trust the std C time
library very much.

here goes:

#include <time.h>
#include <sys/times.h>
#include <unistd.h>
/**
 * Main timing function for zmod_poly_factorise
 */
#define MIN_LENGTH 250
#define MAX_LENGTH 270        //Maximum length of polynomial to be timed
#define NUMBER 3        //Number of random poly's we test to get average
time
void timing()
{
    //Variables
    clock_t start, end;
    double total_time;
    double timings[MAX_LENGTH - MIN_LENGTH];    //store the average time of
poly length [i]
    zmod_poly_t input;
    zmod_poly_factor_t factors;

printf("Computing Timings \n");
    for(unsigned long k = MIN_LENGTH; k < MAX_LENGTH; ++k)
    {
        total_time = 0;
        for(unsigned long i = 0; i < NUMBER; ++i)
        {
            //Set up a polynomial
            zmod_poly_init(input, PRIME);
            randpoly(input, k, PRIME);
            zmod_poly_make_monic(input, input);
            //set up factors
            zmod_poly_factor_init(factors);

            //Begin
            printf(".");
            start = clock();
            //do stuff
            zmod_poly_factorise(factors, input);
            //End
            end = clock();
            printf("/");
            fflush(stdout);
            //Calc timing
            total_time = ((double) (end - start)) / CLOCKS_PER_SEC;

            //clear memory
            zmod_poly_clear(input);
            zmod_poly_factor_clear(factors);
        }
        total_time = ((double) total_time ) / NUMBER;
        timings[k - MIN_LENGTH] = total_time;
    }

    //output the data
    printf("\n\t \t Average Timings: \n");
    printf("Length \t Average Time \n");
    for(unsigned long k=0; k < MAX_LENGTH - MIN_LENGTH; ++k)
        printf("%lu \t %f \n", k + MIN_LENGTH, timings[k]);
}



-- 
Richard