Dabscm Library Reference

(scm math)

Math constants and non-standard numeric operations

Overview

(scm math) collects a few math constants and numeric helpers that aren't part of the standard numeric tower.

Common uses

(import (scm math))

PI              ;; => 3.141592653589793
E               ;; => 2.718281828459045
(factorial 5)   ;; => 120
(sign -5)       ;; => -1
(sign 0)        ;; => 0
(magnitude -3)  ;; => 3

6 bindings

E
(no documentation)
PI
(no documentation)
factorial
Syntax: (factorial n)
Library: (scm math)
Description: Returns the factorial of non-negative integer n (n!). Uses tail
recursion via a named let accumulator.
Example:
  (factorial 0) => 1
  (factorial 5) => 120
magnitude
Syntax: (magnitude z)
Library: (scheme complex)
Description: Returns the magnitude of the complex number z.
  For real numbers, equivalent to abs.
Example:
  (magnitude -3.0) => 3.0
  (magnitude 3+4i) => 5.0
nil
(no documentation)
sign
Syntax: (sign n)
Library: (scm math)
Description: Returns -1 if n is negative, +1 if n is positive, or 0 if n is zero.
Example:
  (sign -5) => -1
  (sign 0)  => 0
  (sign 3)  => 1