Intro to Numpy

#1)Importing Numpy
import numpy as np

#2) Inititlize numpy array
a = np.array([1,3,5,7,9])

#3) Initilize numpy array using list
l = ([1,2,3],[3,6,9],[2,4,6])
a = np.array(l)

print("Array elements\n",a,"\n----------------")

#access elements from array
a[1,2]
print("a[1,2] = ",a[1,2],"\n----------------")
a[1,1:3]
print("a[1,1:3] = ",a[1,1:3],"\n----------------")
a[:,1]
print("a[:,1] = ",a[:,1],"\n----------------")
a[:,0]=[0,9,8]
print("a[:,0]=[0,9,8] = ",a,"\n----------------")

#5) Apply functions on numpy
print("a.min() : ",a.min(),"\n----------------")
print("a.max() : ",a.max(),"\n----------------")
print("a.absolute() : ",np.absolute(a[2]-a[1]),"\n----------------")
np.random.shuffle(a) #random shuffle
print("a.shuffle() : ",a,"\n----------------")
print("a.arange() : ",np.arange(3),"\n----------------")
print("a.zeros() : ",np.zeros((5), dtype=int),"\n----------------")
print("a.ones() : ",np.ones((5), dtype=int),"\n----------------")
print("a.mgrid() : ",np.mgrid[0:3],"\n----------------")
"""
linspace()
-> start  : [optional] start of interval range. By default start = 0
-> stop   : end of interval range
-> restep : If True, return (samples, step). By deflut restep = False
-> num    : [int, optional] No. of samples to generate
-> dtype  : type of output array
"""
print("np.linspace()\n","B\n", np.linspace(2.0, 3.0, num=5, retstep=True), "\n----------------")
print("rand() = ",np.random.rand(5),"\n----------------")
#for 2d array of Random Numbers syntax :- print(np.random.rand(2, 3))
print("sort() = ",np.sort(a, axis = None),"\n----------------")
print("sum() = ",np.sum(a),"\n----------------")
print("matrix() = ",np.matrix([[1,2],[3,4]]),"\n----------------")
print("size() = ",np.size(a),"\n----------------")
"""
OUTPUT

Array elements
 [[1 2 3]
 [3 6 9]
 [2 4 6]]
----------------
a[1,2] =  9
----------------
a[1,1:3] =  [6 9]
----------------
a[:,1] =  [2 6 4]
----------------
a[:,0]=[0,9,8] =  [[0 2 3]
 [9 6 9]
 [8 4 6]]
----------------
a.min() :  0
----------------
a.max() :  9
----------------
a.absolute() :  [1 2 3]
----------------
a.shuffle() :  [[9 6 9]
 [8 4 6]
 [0 2 3]]
----------------
a.arange() :  [0 1 2]
----------------
a.zeros() :  [0 0 0 0 0]
----------------
a.ones() :  [1 1 1 1 1]
----------------
a.mgrid() :  [0 1 2]
----------------
np.linspace()
 B
 (array([2.  , 2.25, 2.5 , 2.75, 3.  ]), 0.25)
----------------
rand() =  [0.36013086 0.63198353 0.68502288 0.27798931 0.92382514]
----------------
sort() =  [0 2 3 4 6 6 8 9 9]
----------------
sum() =  47
----------------
matrix() =  [[1 2]
 [3 4]]
----------------
size() =  9
----------------



"""