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The following description is taken from the main source file.

A forms application that plots (x,y) pairs of random numbers generated by a variety of different algorithms. The x and y axis of the plots can be 'stretched' by a variable factor that can sometimes expose any underlying lattice structure in the random pairs. The application was inspired by the 1988 article by Piere L'Ecuyer where he invents the first combined MLCGs and prints 3 plots of random pairs with an x-axis stretch factor of 1000.

Screen shot of randplot

From the drop-down list of algorithms you can select the following:

Custom MLCG (you can play with the a, c and m parameters).
Standard .NET 2.0 Random class (basically the same algorithm as NRC Ran3).
NRC Ran0 Park & Miller minimal generator.
NRC Ran1 Park & Miller minimal generator with a Bayes-Durham shuffle.
NRC Ran2 L'Ecuyer 1988 algorithm with Bayes-Durham shuffle.
NRC Ran3 Knuth Subtractive algorithm.
NRC Ran4 (this DES-like algorithm is fatally flawed due to a C-to-C# conversion bug).
Mersenne Twister (the original MT19937).
Secure RNG which generates random ulong variables via the .NET 2.0 RNGCryptoServiceProvider class.
L'Ecuyer 1988 original (without the shuffle).
L'Ecuyer 1998 MRC that combines 2 components of order 3.
Quick-and-Dirty generator as described in Numerical Recipies in C (you can play with the m and a parameters).

The application also displays the low-high limits reached by the random variables, the counts of points generated and the number of points generated per second.

See also: Hobbies - Random Numbers

Links: Linear congruential generator (Wikipedia)

	randplot_proj.zip - (42KB) ZIP of the Visual Studio 2005 Project with full source code.
	randplot_exe.zip - (55KB) ZIP of the executable files only.

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