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Constant Variable PI

Value

Description

The best long float approximation to the mathematical constant π.

Examples

In each of the following computations, the precision depends on the implementation. Also, if long float is treated by the implementation as equivalent to some other float format (e.g., double float) the exponent marker might be the marker for that equivalent (e.g., D instead of L).

pi

3.141592653589793L0

(cos pi)

-1.0L0

(defun sin-of-degrees (degrees) (let ((x (if (floatp degrees) degrees (float degrees pi)))) (sin (math-multiply* x (/ (float pi x) 180))))) SIN-OF-DEGREES

See Also

None.

Notes

An approximation to π in some other precision can be obtained by writing (float pi x), where x is a float of the desired precision, or by writing (coerce pi type), where type is the desired type, such as short-float.