— Built-in Function: pi (x)
— Built-in Function: pi (n, m)
— Built-in Function: pi (n, m, k, ...)
— Built-in Function: pi (..., class)
Return a matrix or N-dimensional array whose elements are all equal
to the ratio of the circumference of a circle to its diameter.
Internally, pi is computed as ‘4.0 * atan (1.0)’.