Python/Numpy之加减乘除开方平方幂值三角函数等算数运算

Python/Numpy之加减乘除开方平方幂值三角函数等算数运算

import numpy as np
a = np.array([1,2,3])
b = np.array([2,3,4])

1. 加法：
   add1 = a + b
add2 = np.add(a,b)
2. 减法：
   sub1 = a - b
sub2 = np.subtract(a,b)
3. 乘法：
   mul1 = a * b
mul2 = np.multiply(a,b)
4. 除法：
   div1 = a / b
div2 = np.divide(a,b)
5. 幂指运算开方、平方、指数、对数：
   sqrtx = np.sqrt(a) # 开方
   powerx = np.power(a,2) # 平方
   expx = np.exp(a)
logx = np.log(a)
6. 三角函数：
   sinx = np.sin(a)
cosx = np.cos(a)

>>> import numpy as np
>>> a = np.array([1,2,3])
>>> b = np.array([2,3,4])
# 减法运算
>>> sub1 = a - b
>>> sub1
array([-1, -1, -1])
>>> sub2 = np.subtract(a,b)
>>> sub2
array([-1, -1, -1])
# 加法运算
>>> add1 = a + b
>>> add1
array([3, 5, 7])
>>> add2 = np.add(a,b)
>>> add2
array([3, 5, 7])
# 除法运算
>>> div1 = a / b
>>> div1
array([0.5       , 0.66666667, 0.75      ])
>>> div2 = np.divide(a,b)
>>> div2
array([0.5       , 0.66666667, 0.75      ])
# 乘法运算
>>> mul1 = a * b
>>> mul1
array([ 2,  6, 12])
>>> mul2 = np.multiply(a,b)
>>> mul2
array([ 2,  6, 12])
# 三角函数
>>> sinx = np.sin(a)
>>> sinx
array([0.84147098, 0.90929743, 0.14112001])
>>> cosx = np.cos(a)
>>> cosx
array([ 0.54030231, -0.41614684, -0.9899925 ])
>>> tanx = np.tan(a)
>>> tanx
array([ 1.55740772, -2.18503986, -0.14254654])
# 幂指数运算
>>> expx = np.exp(a)
>>> expx
array([ 2.71828183,  7.3890561 , 20.08553692])
>>> logx = np.log(a)
>>> logx
array([0.        , 0.69314718, 1.09861229])
# 开方运算
>>> sqrtx = np.sqrt(a)
>>> sqrtx
array([1.        , 1.41421356, 1.73205081])
# 平方运算
>>> powerx = np.power(a,2)
>>> powerx
array([1, 4, 9], dtype=int32)

更多Python数据科学相关见专题Python数据科学技能索引