Question

So I get the time at the beginning of the code, run it, and then get the time.

struct timeval begin, end;
gettimeofday(&begin, NULL);

//code to time

gettimeofday(&end, NULL);
//get the total number of ms that the code took:
unsigned int t = end.tv_usec - begin.tv_usec;

Now I want to print it out in the form “**code took 0.007 seconds to run” or something similar.

So two problems:

1) t seems to contain a value of the order 6000, and I KNOW the code didn’t take 6 seconds to run.

2) How can I convert t to a double, given that it’s an unsigned int? Or is there an easier way to print the output the way I wanted to?

Answer 1

1) That’s because usec is not 6000 milliseconds, it’s 6000 microseconds (6 milliseconds or 6 one-thousandths of a second).

2) Try this: (double)t / 1000000 That will convert t to a double, and then divide it by one million to find the number of seconds instead of the number of microseconds.