Welcome to the Harris Geospatial product documentation center. Here you will find reference guides, help documents, and product libraries.

  >  Docs Center  >  IDL Reference  >  Advanced Math and Stats  >  IMSL_HYPERGEOCDF




The IMSL_HYPERGEOCDF function evaluates the hypergeometric distribution function.

The IMSL_HYPERGEOCDF function evaluates the distribution function of a hypergeometric random variable with parameters n, l, and m. The hypergeometric random variable X can be thought of as the number of items of a given type in a random sample of size n that is drawn without replacement from a population of size l containing m items of this type.

The probability function is:

where i = max(0, n – l + m).

If k is greater than or equal to i and less than or equal to min(n, m), IMSL_BINOMIALCDF sums the terms in this expression for j going from i up to k; otherwise, 0 or 1 is returned, as appropriate. To avoid rounding in the accumulation, IMSL_BINOMIALCDF performs the summation differently, depending on whether or not k is greater than the mode of the distribution, which is the greatest integer in (m + 1) (n + 1)/(l + 2).

© 2018 Harris Geospatial Solutions, Inc. |  Legal
My Account    |    Store    |    Contact Us