Hypergeometric functions
Hypergeometric functions as per the Gnu Scientific Library reference manual section 7.21 and AMS-55, chapters 13 and 15. These functions are declared in header file gsl_sf_hyperg.h
hyperg_0F1(c, x, give=FALSE, strict=TRUE) hyperg_1F1_int(m, n, x, give=FALSE, strict=TRUE) hyperg_1F1(a, b, x, give=FALSE, strict=TRUE) hyperg_U_int(m, n, x, give=FALSE, strict=TRUE) hyperg_U(a, b, x, give=FALSE, strict=TRUE) hyperg_2F1(a, b, c, x, give=FALSE, strict=TRUE) hyperg_2F1_conj(aR, aI, c, x, give=FALSE, strict=TRUE) hyperg_2F1_renorm(a, b, c, x, give=FALSE, strict=TRUE) hyperg_2F1_conj_renorm(aR, aI, c, x, give=FALSE, strict=TRUE) hyperg_2F0(a, b, x, give=FALSE, strict=TRUE)
x
: input: real values
a,b,c
: input: real values
m,n
: input: integer values
aR,aI
: input: real values
give
: Boolean with TRUE
meaning to return a list of three items: the value, an estimate of the error, and a status number.
strict
: Boolean, with TRUE
meaning to return NaN
if status is an error
https://www.gnu.org/software/gsl/
Robin K. S. Hankin
The circle of convergence of the Gauss hypergeometric series is theunit circle |z|=1 (AMS, page 556).
There is a known issue in hyperg_2F1()
in GSL-2.6, https://savannah.gnu.org/bugs/?54998 and the package returns the erroneous value given by GSL.
hyperg_0F1(0.1,0.55) hyperg_1F1_int(2,3,0.555) hyperg_1F1(2.12312,3.12313,0.555) hyperg_U_int(2, 3, 0.555) hyperg_U(2.234, 3.234, 0.555)