Function rgsl::blas::level1::drotg

pub fn drotg(
    a: &mut [f64], 
    b: &mut [f64], 
    c: &mut [f64], 
    d: &mut [f64]
) -> Value

This function computes a Givens rotation (c,s) which zeroes the vector (a,b),

[  c  s ] [ a ] = [ r ]

[ -s  c ] [ b ]   [ 0 ]

The variables a and b are overwritten by the routine.