I’m working on a problem that has to do with calculating angles of refraction and what not. However, it seems that I’m unable to use the numpy.sin() function in degrees. I have tried to use numpy.degrees() and numpy.rad2deg().

`numpy.sin(90) numpy.degrees(numpy.sin(90))`

Both return ~ 0.894 and ~ 51.2 respectively.

Thanks for your help.

**Answer**

You don’t want to convert *to* degrees, because you already have your number (90) in degrees. You need to convert 90 *from* degrees to radians, and you need to do it *before* you take the sine:

```
>>> np.sin(np.deg2rad(90))
1.0
```

(You can use either `deg2rad`

or `radians`

.)

**Attribution***Source : Link , Question Author : Daniil Ukhorskiy , Answer Author : BrenBarn*