numpy.cos() in Python

numpy.cos(x[, out]) = ufunc 'cos') : This mathematical function helps user to calculate trigonometric cosine for all x(being the array elements). 
Parameters : 
 

array : [array_like]elements are in radians. 

2pi Radians = 360 degrees

Return : 
 

An array with trigonometric cosine 
of x for all x i.e. array elements 

  
Code #1 : Working 
 

Output : 
 

Input array : 
 [0, 1.5707963267948966, 1.0471975511965976, 3.141592653589793]

Cosine values : 
 [ 1.00000000e+00 6.12323400e-17 5.00000000e-01 -1.00000000e+00]

  
Code #2 : Graphical representation 
 

Output : 
 

in_array : [-6.28318531 -5.62179738 -4.96040945 -4.29902153 -3.6376336 -2.97624567
 -2.31485774 -1.65346982 -0.99208189 -0.33069396 0.33069396 0.99208189
 1.65346982 2.31485774 2.97624567 3.6376336 4.29902153 4.96040945
 5.62179738 6.28318531]

out_array : [ 1. 0.78914051 0.24548549 -0.40169542 -0.87947375 -0.9863613
 -0.67728157 -0.08257935 0.54694816 0.94581724 0.94581724 0.54694816
 -0.08257935 -0.67728157 -0.9863613 -0.87947375 -0.40169542 0.24548549
 0.78914051 1. ]