QWGTS defines the weight functions used by QC25S.
Author:
Robert Piessens, Elise de Doncker-Kapenger, Christian Ueberhuber, David Kahaner
Reference:
Robert Piessens, Elise de Doncker-Kapenger, Christian Ueberhuber, David Kahaner, QUADPACK, a Subroutine Package for Automatic Integration, Springer Verlag, 1983
Parameters:
Input, real X, the point at which the weight function is evaluated.
Input, real A, B, the endpoints of the integration interval.
Input, real ALFA, BETA, exponents that occur in the weight function.
Input, integer INTEGR, specifies which weight function is used: 1. W(X) = (X-A)ALFA * (B-X)BETA 2, W(X) = (X-A)ALFA * (B-X)BETA * log (X-A) 3, W(X) = (X-A)ALFA * (B-X)BETA * log (B-X) 4, W(X) = (X-A)ALFA * (B-X)BETA * log (X-A) * log(B-X)
Output, real QWGTS, the value of the weight function at X.
Type | Intent | Optional | Attributes | Name | ||
---|---|---|---|---|---|---|
real, | intent(in) | :: | x | |||
real, | intent(in) | :: | a | |||
real, | intent(in) | :: | b | |||
real, | intent(in) | :: | alfa | |||
real, | intent(in) | :: | beta | |||
integer, | intent(in) | :: | integr |