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Algorithm Timing

Hey guys quick question that I can't seem to get.
I'm trying to show how a program I wrote improves (or worsens) as the number of processors increases. However, I can't for the life of me determine a way to represent the time it take for one of the funcitons to run.

Code:

    double term = start;

    double newTerm = 0;

    double precision=1e-6;

    double sum = start;

    int i =0;

    // Calculate each new term and add to total 

    //Stop when the previous term is less than the precision

    for( i = p;term > precision ; )

    {

        double newFac = 1;

        // Calculate the nessesary jump given i and the (n)umber of processors

        for(int j = 1;j <= n ; j++ )

        {

            newFac = newFac * ( x / ( i+ j ));

            

        }

        newTerm = newFac;

        //Get new term

        term = term * newTerm;

        // Increment sum by new term

        sum += term;

        i=i+n;

    }

I know the inner loop runs n times each time the main loop runs. But I can't figure out how to determine the number of times the main loop runs in any sort of formulaic way.

Yes, it's homework, but 90% of the assignment was developing and writing the algorithm.
Thanks

Is this it, because I don't see any declarations for start, p and x. It would be nice to know what those are.

If you can use perl, there are some good benchmarking features in the benchmark module.

I've used them a few times to test performance of different algorithms.

http://www.perldoc.com/perl5.8.0/lib/Benchmark.html

Are we talking theoretical big-oh stuff or empirical timing, or both? You can use System.currentTimeMillis() for actual timings in milliseconds.

Theoretical.. You're incrementing your outer loop by a constant? 0(n^2) then.. (Can't tell what n is..)