This is exclusively training program for NumPy

What is NumPy? It's numerical python package, built on top of C language.

Provides numerical operations on large quantities of data.
Doing Mathematical functions

Data Type Vs Data Structure Data type can be int, str, float, bool, list, tuple, dict and set

Data Structure is a method to organize and manage data, it enables to store and allows computations

NumPy is an open source, used to work with arrays.

Key features of NumPy

Create N dimensional array, also called Nd array.
Broadcasting- Universal functions(Ufuncs)
Efficient computation( Vectorization )
Linear Algebra

NumPy official documents https://numpy.org/ latest release is 2.0

Array looks like list, only difference, it explicitly shows array

import numpy as np print(np.array([1,2,4])) #1D print(np.array([[1,2],[2,3]])) #2D print(np.array([[[1,2,3],[4,5,6],[7,8,9]]])) #3D [1 2 4] [[1 2] [2 3]] [[[1 2 3] [4 5 6] [7 8 9]]]

a= [[1,2,3,4],[5,6,7,8]] #what would be the length len(a) 2

How to recognize list is 1d or 2d, the best way to have a look at the starting of the list, how many square brackets it contains.

list_2d=[[1,2,3,4],[5,6,7,8],[9,10,11,12]]

print(list_2d) #[[1,2,3,4],[5,6,7,8],[9,10,11,12]]

print(list_2d[0]) #[1, 2, 3, 4]

for i in list_2d: print(i)

""" [1, 2, 3, 4] [5, 6, 7, 8] [9, 10, 11, 12] """

for i in list_2d: for j in i: print(j)

] """

for i in list_2d: for j in i: print(j)

output [1, 2, 3, 4] [5, 6, 7, 8] [9, 10, 11, 12] 1 2 3 4 5 6 7 8 9 10 11 12

example of 3d array

list_3d=[ [ [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] ] ]

len(list_3d) #3

list_3d[0][0][1] #2

for i in list_3d: print(i)

[[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]]

for i in list_3d: print(i[0])

[1, 2, 3] [10, 11, 12] [19, 20, 21]

for i in list_3d: for j in i: print(j) 7] 0s for i in list_3d: for j in i: print(j)

[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]

for i in list_3d: for j in i: for k in j: print(k)

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

list_3d[1][2][1]=100 list_3d [[[1, 2, 3], [4, 5, 6], [7, 8, 9]], [[10, 11, 12], [13, 14, 15], [16, 100, 18]], [[19, 20, 21], [22, 23, 24], [25, 26, 27]]]

Note: whenever you do slicing of the element it never gives out of index error. but during indexing it gives index out or range error Ex: list_2d=[ [1,2,3,4], [5,6,7,8], [9,10,11,12] ]

list_2d[1:2] #[[5, 6, 7, 8]]

list_2d[1:2][1:4] #[] No error during slicing of the list

list_2d[3] #IndexError: list index out of range

kumarpac / pythonbasicprogram