Numpy in python

  • Numpy is a general-purpose array-processing package.
  • It provides a high-performance multidimensional array object, and tools for working with these arrays.
  • It is the fundamental package for scientific computing with Python.
  • Besides its obvious scientific uses, Numpy can also be used as an efficient multi-dimensional container of generic data.

Arrays in Numpy

  • Array in Numpy is a table of elements (usually numbers), all of the same type, indexed by a tuple of positive integers.
  • In Numpy, number of dimensions of the array is called rank of the array.
  • A tuple of integers giving the size of the array along each dimension is known as shape of the array.
  • An array class in Numpy is called as ndarray.
  • Elements in Numpy arrays are accessed by using square brackets and can be initialized by using nested Python Lists.

Creating a Numpy Array

  • Arrays in Numpy can be created by multiple ways, with various number of Ranks, defining the size of the Array.
  • Arrays can also be created with the use of various data types such as lists, tuples, etc.
  • The type of the resultant array is deduced from the type of the elements in the sequences.

Note: Type of array can be explicitly defined while creating the array.

# Python program for
# Creation of Arrays
import numpy as np
# Creating a rank 1 Array
arr = np.array([1, 2, 3])
print("Array with Rank 1: \n",arr)
# Creating a rank 2 Array
arr = np.array([[1, 2, 3],[4, 5, 6]])
print("Array with Rank 2: \n", arr)
# Creating an array from tuple
arr = np.array((1, 3, 2))
print("\nArray created using "
"passed tuple:\n", arr) 

Output:

Array with Rank 1:
 [1 2 3]
Array with Rank 2: 
[[1 2 3]
[4 5 6]]
Array created using passed tuple:
 [1 3 2]

Posted on by