# naginterfaces.library.blas.zcsgs¶

naginterfaces.library.blas.zcsgs(t)[source]

zcsgs reconstructs the parameters (complex) and (real) of a complex plane rotation from the tangent of that rotation.

For full information please refer to the NAG Library document for f06cd

https://www.nag.com/numeric/nl/nagdoc_28.7/flhtml/f06/f06cdf.html

Parameters
tcomplex

The value , the tangent of the rotation.

Returns
ccomplex

The value , the cosine of the rotation.

sfloat

The value , the sine of the rotation.

Notes

No equivalent traditional C interface for this routine exists in the NAG Library.

zcsgs reconstructs the parameters (complex) and (real) of a complex plane rotation, from the value of the tangent , as returned by zrotgs():

If , where is the machine precision, the function sets: