# Trig: Trig functions In gsl: Wrapper for the Gnu Scientific Library

 Trig R Documentation

## Trig functions

### Description

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

### Usage

```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

### Author(s)

Robin K. S. Hankin

### References

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

### 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)

```

gsl documentation built on Feb. 16, 2023, 10:32 p.m.