PI ( Value of pi )
DOUBLE PRECISION FUNCTION PI ( )
Return the value of pi (the ratio of the circumference of
a circle to its diameter).
The function returns the value of pi.
The function returns the value of pi (the ratio of a circle's
circumference to its diameter), determined by the ACOS function.
PI = ACOS ( -1.D0 )
The first time the function is referenced, the value is computed
as shown above. The value is saved, and returned directly upon
The code fragment below illustrates the use of PI.
C Compute the polar radius,
C 1 + e cos(theta)
C at evenly spaced values of the polar angle, theta.
DELTA = PI() / N
DO I = 0, N
R(I) = P / (1.D0 + ECC * COS(I*DELTA))
W.L. Taber (JPL)
I.M. Underwood (JPL)
SPICELIB Version 1.0.1, 10-MAR-1992 (WLT)
Comment section for permuted index source lines was added
following the header.
SPICELIB Version 1.0.0, 31-JAN-1990 (WLT) (IMU)