tkbx - 2 months ago 31

Python Question

In the python.org math library, I could only find

`math.cos(x)`

Here's my code:

`import math`

x = math.cos(1)

y = x * 180 / math.pi

print y

30.9570417874

My calculator, on deg, gives me:

`cos(1)`

0.9998476...

Answer

Python includes two functions in the `math`

package; `radians`

converts degrees to radians, and `degrees`

converts radians to degrees.

To match the output of your calculator you need:

```
>>> math.cos(math.radians(1))
0.9998476951563913
```

Note that all of the trig functions convert between an angle and the ratio of two sides of a triangle. cos, sin, and tan take an angle in radians as input and return the ratio; acos, asin, and atan take a ratio as input and return an angle in radians. You only convert the angles, never the ratios.