Clausen functions
Clausen functions as per the Gnu Scientific Library section 7.6. These functions are declared in header file gsl_sf_clausen.h
clausen(x, give=FALSE, strict=TRUE)
x
: 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
Robin K. S. Hankin
https://www.gnu.org/software/gsl/
x <- (0:30)*pi/180 clausen(x) #table 27.8, p1006