.\

cgrandomwald.pro

top cgRandomWald

Utility

result = cgRandomWald( [seed] [, dims] [, MU=double] [, LAMBDA=double])

This function creates a vector of N random numbers using an Inverse Gaussian Distribution, which is also known as the Wald Distribution. The reference for the code can be found at http://en.wikipedia.org/wiki/Inverse_Gaussian_distribution.

Parameters

seed in optional

The seed for the random number generator. If undefined, on output will have the seed used by the IDL RandomU function. See the documentation for RandomU for additional information.

dims in optional type=integer

A scalar or integer array defining the dimensions of the result. If no dimensions are specified, a single random number is returned. If Dims is a scalar, a 1D vector of that number of values will be returned.

Keywords

MU in optional type=double default=1.0

The mean of the distribution.

LAMBDA in optional type=double default=1.0

The shape parameter of the distribution. As lambda tends to infinity, the inverse distribution becomes more like a normal distribution.

Examples

For example, to create 100 random numbers, using the Wald distribution:

wald = cgRandomWald(seed, 100)

To create a 20-column by 10-row array of random numbers:

  wald = cgRandoWald(seed, [20,10])

Author information

Author:

FANNING SOFTWARE CONSULTING:

  David W. Fanning
  1645 Sheely Drive
  Fort Collins, CO 80526 USA
  Phone: 970-221-0438
  E-mail: david@idlcoyote.com
  Coyote's Guide to IDL Programming: http://www.idlcoyote.com

Copyright:

History:

Written, 25 Oct 2012, by David W. Fanning.

File attributes

Modification date:	Fri Mar 27 11:07:37 2015
Lines:	117
Docformat:	rst rst

Coyote Graphics Routines

Date: Fri Mar 27 12:14:20 2015