The NumPy cos() function is used to calculate trigonometric cosine of given angle in radians.

### Syntax

```numpy.cos(x, out=None)
```

### Parameters

 `x` `Required. `Specify array (array_like) containing elements as angles in radians of which the trigonometric cosine is calculated. `out` `Optional. `Specify a location into which the result is stored. If provided, it must have a shape that the inputs broadcast to. If not provided or None, a freshly-allocated array is returned.

### Return Value

Returns the cosine of each element of x.

### Example:

In the below example, numpy cos() function is used to calculate the cosine of each element present in array Arr.

```import numpy as np

Arr = np.array([0, 30, 60, 90])
#converting the angles in radians
Arr = Arr*np.pi/180

print("The cos value of angles:")
print(np.cos(Arr))
```

The output of the above code will be:

```The cos value of angles:
[  1.00000000e+00   8.66025404e-01   5.00000000e-01   6.12323400e-17]
```

❮ NumPy - Functions