I have been looking for a program to calculate pi to a digit given

all I have seen so far are

100 digits

1000 digits

and

1001 digits

why can't there be one to display PI to any amount of digits?

so I don't think it is possible for C basic C to compute pi.

In calculus the equation (at least, my way of getting the equation is right)

pi = 2 ( integral(sqrt(1-x^2)dx, from -1 to 1)

I derived this 2 years ago, I think there is also a series to do this but that is basically it right there.

If anyone finds a program to calculuate pi let me know. I would really appreciate it.