Numpy

numpy_indexing_slicing5.py

import numpy as np

x = np.arange(35)
print(x)

#[Output]:
#[ 0  1  2  3  4  5  6  7  8  9 10 11 12 13 14 15 16 17 18 19 20 21 22 23
# 24 25 26 27 28 29 30 31 32 33 34]


## If we want elements having value >20
## Comparision operator should be used first and it will return boolean array.

b = x>20

print(b)

#[Output]:
#[False False False False False False False False False False False False
# False False False False False False False False False  True  True  True
#  True  True  True  True  True  True  True  True  True  True  True]


## It will return elements which are having True value in b
print(x[b])

#[Output]:
#[21 22 23 24 25 26 27 28 29 30 31 32 33 34]

## We can merge these 2 steps in one step
print(x[x>20])

#[Output]:
#[21 22 23 24 25 26 27 28 29 30 31 32 33 34]