NumPy ufuncs

What are ufuncs?

ufuncs stands for "Universal Functions" and they are NumPy functions that operate on thendarray object.

ufuncs are used to implement vectorization in NumPy which is way faster than iterating over elements.

They also provide broadcasting and additional methods like reduce, accumulate etc. that are very helpful for computation.

ufuncs also take additional arguments, like:

where: boolean array or condition defining where the operations should take place.
dtype: defining the return type of elements.
out: output array where the return value should be copied.

Converting iterative statements into a vector based operation is called vectorization.

It is faster as modern CPUs are optimized for such operations.

list 1: [1, 2, 3, 4]
list 2: [4, 5, 6, 7]

One way of doing it is to iterate over both of the lists and then sum each elements.

Without ufunc, we can use Python's built-in zip() method:

x = [1, 2, 3, 4]
y = [4, 5, 6, 7]
z = []

for i, j in zip(x, y):
  z.append(i + j)
print(z)

NumPy has a ufunc for this, called add(x, y) that will produce the same result.

With ufunc, we can use the add() function:

import numpy as np

x = [1, 2, 3, 4]
y = [4, 5, 6, 7]
z = np.add(x, y)

print(z)