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Function Reference: hygepdf

statistics: y = hygepdf (x, m, k, n)
statistics: y = hygepdf (…, "vectorexpand")

Hypergeometric probability density function (PDF).

For each element of x, compute the probability density function (PDF) of the hypergeometric distribution with parameters m, k, and n. The size of y is the common size of x, m, k, and n. A scalar input functions as a constant matrix of the same size as the other inputs.

This is the probability of obtaining x marked items when randomly drawing a sample of size n without replacement from a population of total size m containing k marked items. The parameters m, k, and n must be positive integers with k and n not greater than m.

If the optional parameter vectorexpand is provided, x may be an array with size different from parameters m, k, and n (which must still be of a common size or scalar). Each element of x will be evaluated against each set of parameters m, k, and n in columnwise order. The output y will be an array of size r x s, where r = numel (m), and s = numel (x).

Further information about the hypergeometric distribution can be found at https://en.wikipedia.org/wiki/Hypergeometric_distribution

See also: hygecdf, hygeinv, hygernd, hygestat

Source Code: hygepdf

Example: 1

  

 ## Plot various PDFs from the hypergeometric distribution
 x = 0:60;
 y1 = hygepdf (x, 500, 50, 100);
 y2 = hygepdf (x, 500, 60, 200);
 y3 = hygepdf (x, 500, 70, 300);
 plot (x, y1, "*b", x, y2, "*g", x, y3, "*r")
 grid on
 xlim ([0, 60])
 ylim ([0, 0.18])
 legend ({"m = 500, k = 50, μ = 100", "m = 500, k = 60, μ = 200", ...
          "m = 500, k = 70, μ = 300"}, "location", "northeast")
 title ("Hypergeometric PDF")
 xlabel ("values in x (number of successes)")
 ylabel ("density")
plotted figure