c - Code benchmarking statistics - -

as wrote in previous topic: benchmarking code - doing right? need find way benchmark statistics, average, mean, standard deviation, etc. how can using methods posted? notice use solution benchmark code time interval, not calling function many times. ideas?

i came one, dont know if correct (pseudocode):

buffsize = 1024; buffer [buffsize]; totalcycles = 0  // arrays walltimeresults = [] cputimeresults = []  // benchmarking in (0, iterations):    start = walltime();    fun2measure(args, buffer);    end = walltime();    walltimeresults[i] = end - start;     start = cputime();    fun2measure(args, buffer);    end = cputime();    cputimeresults[i] = end - start;     c1 = cyclecount();    fun2measure(args, buffer);    c2 = cyclecount();     cyclesperbyte = c2-c1/(buffsize);    totalcycles += cyclesperbyte;  in range (0, iterations) : sum += walltimeresults[i]; avg_wall_time = sum / iterations;  sum = 0;  in range (0, iterations) : sum += cputimeresults[i]; avg_cpu_time = sum / iterations;  avg_cycles = totalcycles / iterations; 

is correct? how mean, standard deviation, etc?

your average looks ok.

mean (i.e. average) is

mean = 1/n * sum( x[i] ) 

standard deviation square root of variance:

sigma = sqrt( 1/n * sum( (x[i]-mean)^2 )