hygepdf

Hypergeometric probability density function

Syntax

Y = hygepdf(X,M,K,N)

Description

Y = hygepdf(X,M,K,N) computes the hypergeometric pdf at each of the values in X using the corresponding size of the population, M, number of items with the desired characteristic in the population, K, and number of samples drawn, N. X, M, K, and N can be vectors, matrices, or multidimensional arrays that all have the same size. A scalar input is expanded to a constant array with the same dimensions as the other inputs.

The parameters in M, K, and N must all be positive integers, with N ≤ M. The values in X must be less than or equal to all the parameter values.

The hypergeometric pdf is

$y = f (x | M, K, N) = \frac{(\begin{matrix} K \\ x \end{matrix}) (\begin{matrix} M - K \\ N - x \end{matrix})}{(\begin{matrix} M \\ N \end{matrix})}$

The result, y, is the probability of drawing exactly x of a possible K items in n drawings without replacement from a group of M objects.

Examples

Suppose you have a lot of 100 floppy disks and you know that 20 of them are defective. What is the probability of drawing 0 through 5 defective floppy disks if you select 10 at random?

p = hygepdf(0:5,100,20,10)
p =
  0.0951  0.2679  0.3182  0.2092  0.0841  0.0215

Extended Capabilities

C/C++ Code Generation
Generate C and C++ code using MATLAB® Coder™.

GPU Arrays
Accelerate code by running on a graphics processing unit (GPU) using Parallel Computing Toolbox™.

This function fully supports GPU arrays. For more information, see Run MATLAB Functions on a GPU (Parallel Computing Toolbox).

Version History

Introduced before R2006a