Trig function

Trig functions

Trig functions as per the Gnu Scientific Library, reference manual section 7.30. These functions are declared in header file gsl_sf_trig.h

gsl_sf_sin(x, give=FALSE, strict=TRUE)
gsl_sf_cos(x, give=FALSE, strict=TRUE)
hypot(x, y, give=FALSE, strict=TRUE)
sinc(x, give=FALSE, strict=TRUE)
complex_sin(zr, zi=NULL, r.and.i=TRUE, give=FALSE, strict=TRUE)
complex_cos(zr, zi=NULL, r.and.i=TRUE, give=FALSE, strict=TRUE)
lnsinh(x, give=FALSE, strict=TRUE)
lncosh(x, give=FALSE, strict=TRUE)

Arguments

• x,y: input: real values

• zr: In gamma_complex(), the real part of the argument

• zi: In complex_sin() et seq, the imaginary part of the argument. If missing (ie takes the default value of NULL), interpret zr as complex, even if real

• r.and.i: In complex_sin() et seq, Boolean variable with default value of TRUE meaning to return a complex variable as per the details section below; and FALSE meaning to return the values as advertised in the GSL manual

• 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

References

https://www.gnu.org/software/gsl/

Author(s)

Robin K. S. Hankin

Examples

x <- seq(from=0,to=2,by=0.01)
gsl_sf_sin(x)   #table xx of Ab and St
gsl_sf_cos(x)   #table xx of Ab and St

f <- function(x){abs(sin(x+1)-sin(x)*cos(1)-cos(x)*sin(1))}
g <-
function(x){abs(gsl_sf_sin(x+1)-gsl_sf_sin(x)*gsl_sf_cos(1)-gsl_sf_cos(x)*gsl_sf_sin(1))}

f(100000:100010)
g(100000:100010)