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5.6.2 Inexact Random Numbers

(require 'random-inexact)

Function: random:uniform
Function: random:uniform state

Returns an uniformly distributed inexact real random number in the range between 0 and 1.

Function: random:exp
Function: random:exp state

Returns an inexact real in an exponential distribution with mean 1. For an exponential distribution with mean u use (* u (random:exp)).

Function: random:normal
Function: random:normal state

Returns an inexact real in a normal distribution with mean 0 and standard deviation 1. For a normal distribution with mean m and standard deviation d use (+ m (* d (random:normal))).

Procedure: random:normal-vector! vect
Procedure: random:normal-vector! vect state

Fills vect with inexact real random numbers which are independent and standard normally distributed (i.e., with mean 0 and variance 1).

Procedure: random:hollow-sphere! vect
Procedure: random:hollow-sphere! vect state

Fills vect with inexact real random numbers the sum of whose squares is equal to 1.0. Thinking of vect as coordinates in space of dimension n = (vector-length vect), the coordinates are uniformly distributed over the surface of the unit n-shere.

Procedure: random:solid-sphere! vect
Procedure: random:solid-sphere! vect state

Fills vect with inexact real random numbers the sum of whose squares is less than 1.0. Thinking of vect as coordinates in space of dimension n = (vector-length vect), the coordinates are uniformly distributed within the unit n-shere. The sum of the squares of the numbers is returned.