📜  NumPy按位运算符

📅  最后修改于: 2020-10-27 02:20:52             🧑  作者: Mango

NumPy按位运算符

Numpy提供以下按位运算运算符。

SN Operator Description
1 bitwise_and It is used to calculate the bitwise and operation between the corresponding array elements.
2 bitwise_or It is used to calculate the bitwise or operation between the corresponding array elements.
3 invert It is used to calculate the bitwise not the operation of the array elements.
4 left_shift It is used to shift the bits of the binary representation of the elements to the left.
5 right_shift It is used to shift the bits of the binary representation of the elements to the right.

按位与运算

NumPy提供了bitwise_and()函数,该函数用于计算两个操作数的bitwise_and运算。

对操作数的二进制表示形式的相应位执行按位与运算。如果操作数中的两个对应位都设置为1,则仅AND结果中的结果位将设置为1,否则将设置为0。

import numpy as np

a = 10
b = 12

print("binary representation of a:",bin(a))
print("binary representation of b:",bin(b))
print("Bitwise-and of a and b: ",np.bitwise_and(a,b))

输出:

binary representation of a: 0b1010
binary representation of b: 0b1100
Bitwise-and of a and b:  8

和真值表

当且仅当两个位均为1时,两个位的AND结果的输出为1,否则为0。

A B AND (A, B)
0 0 0
0 1 0
1 0 0
1 1 1

按位或运算符

NumPy提供了bitwise_or()函数,该函数用于计算两个操作数的按位或运算。

对操作数的二进制表示形式的相应位执行按位或运算。如果操作数中的相应位之一设置为1,则OR结果中的结果位将设置为1;否则,结果为1。否则它将设置为0。

import numpy as np

a = 50
b = 90
print("binary representation of a:",bin(a))
print("binary representation of b:",bin(b))
print("Bitwise-or of a and b: ",np.bitwise_or(a,b))

输出:

binary representation of a: 0b110010
binary representation of b: 0b1011010
Bitwise-or of a and b:  122

或真相表

如果一位中的一位为1,则两位的或结果的输出为1,否则为0。

A B Or (A, B)
0 0 0
0 1 1
1 0 1
1 1 1

反转操作

它用于计算按位而不是给定操作数的运算。如果在函数传递有符号整数,则返回2的补码。

考虑以下示例。

import numpy as np

arr = np.array([20],dtype = np.uint8)
print("Binary representation:",np.binary_repr(20,8))

print(np.invert(arr))

print("Binary representation: ", np.binary_repr(235,8))

输出:

Binary representation: 00010100
[235]
Binary representation:  11101011

它将操作数的二进制表示形式的位向左移动指定位置。从右边追加相等数量的0。考虑以下示例。

import numpy as np

print("left shift of 20 by 3 bits",np.left_shift(20, 3))

print("Binary representation of 20 in 8 bits",np.binary_repr(20, 8))

print("Binary representation of 160 in 8 bits",np.binary_repr(160,8))

输出:

left shift of 20 by 3 bits 160
Binary representation of 20 in 8 bits 00010100
Binary representation of 160 in 8 bits 10100000

右移操作

它将操作数二进制表示形式的位向右移动指定位置。从左侧追加相等数量的0。考虑以下示例。

import numpy as np

print("left shift of 20 by 3 bits",np.right_shift(20, 3))

print("Binary representation of 20 in 8 bits",np.binary_repr(20, 8))

print("Binary representation of 160 in 8 bits",np.binary_repr(160,8))

输出:

left shift of 20 by 3 bits 2
Binary representation of 20 in 8 bits 00010100
Binary representation of 160 in 8 bits 10100000