Python Numpy库函数使用

Posted 2020-10-19 Rhys_Wang

NumPy的操作介绍

import numpy as np

print "Generate 1*10 matrix"
a=np.arange(1,11)**2
b=np.arange(1,11)**3
c=a+b
print c
print c.shape

print "create a 2*10 matrix"
m=np.array([np.arange(10),np.arange(10)]) #create a 2*10 matrix
print m
print m.shape

print "generate zero matrix"
z1=np.zeros(10,dtype=np.int8) #create zero matrix
z2=np.zeros([3,4])
print z1 
print z2

print "generate empty matrix"
e=np.empty([2,2]) #create empty matrix
print e

print "create identity matrix with data type equals int8"
eye1=np.eye(5,dtype=np.int8) #create identity matrix
print eye1
print eye1[0,0] #get element by index
print eye1[3,4]

print "calculation between two matrix"
arr1=np.array([[1,2,3],[4,5,6]]) #calculation between two matrix
arr2=arr1*arr1
print arr1
print arr2
print arr2-arr1
print arr2/arr1
print arr2%arr1

print "calculation between a matrix and a number"
print 1/arr1
print arr1*0.3
print arr1+0.08
print arr1-0.33