Accession Number:

ADA031812

Title:

Computation of the Incomplete Gamma Function Ratios

Descriptive Note:

Final rept.

Corporate Author:

NAVAL SURFACE WEAPONS CENTER DAHLGREN LAB VA

Personal Author(s):

Report Date:

1976-04-01

Pagination or Media Count:

86.0

Abstract:

A method, made up of several algorithms, is given for computing the incomplete gamma function ratio, Pa, x and its complement Qa, x for all real arguments a 0, x or 0. The difficult case when a and x are large is treated by a modified version of Takenagas method. The resulting computer program is efficient, yields both P and Q correctly to within 1 unit in the twelfth significant digit, or, at the users option, to within one unit in the sixth or third significant digit. A FORTRAN listing of the program is included.

Subject Categories:

  • Theoretical Mathematics
  • Computer Programming and Software

Distribution Statement:

APPROVED FOR PUBLIC RELEASE