numpy中一元、二元及聚合函数的简单运用
作者:互联网
import numpy as np
a = np.random.randint(-10,20,size=(4,5))
a
array([[ 14, 10, 17, 15, 17],
[ 3, -6, 10, 8, -8],
[ 12, 5, -1, 12, 17],
[ 2, 13, 13, -10, 3]])
b = np.random.randint(0,10,size=(4,5))
b
array([[9, 2, 9, 1, 8],
[0, 7, 1, 8, 4],
[0, 2, 1, 7, 5],
[2, 1, 6, 0, 9]])
#一元函数的应用aba,sqrt,square,exp,log,log10,log2,log1p,sign,
c = np.abs(a)
c
array([[14, 10, 17, 15, 17],
[ 3, 6, 10, 8, 8],
[12, 5, 1, 12, 17],
[ 2, 13, 13, 10, 3]])
d = np.sqrt(c)
d
array([[3.74165739, 3.16227766, 4.12310563, 3.87298335, 4.12310563],
[1.73205081, 2.44948974, 3.16227766, 2.82842712, 2.82842712],
[3.46410162, 2.23606798, 1. , 3.46410162, 4.12310563],
[1.41421356, 3.60555128, 3.60555128, 3.16227766, 1.73205081]])
e = np.square(b)
e
array([[ 9],
[ 0],
[ 1],
[25]], dtype=int32)
f = np.exp(b)
f
array([[ 20.08553692],
[ 1. ],
[ 2.71828183],
[148.4131591 ]])
g = np.log(b)
g
<ipython-input-12-6f4b0dbe2fee>:1: RuntimeWarning: divide by zero encountered in log
g = np.log(b)
array([[1.09861229],
[ -inf],
[0. ],
[1.60943791]])
h = np.sign(a)
h
array([[ 1, 1, 1, 1, 1],
[ 1, -1, 1, 1, -1],
[ 1, 1, -1, 1, 1],
[ 1, 1, 1, -1, 1]])
j = np.ceil(a)
j
array([[ 14., 10., 17., 15., 17.],
[ 3., -6., 10., 8., -8.],
[ 12., 5., -1., 12., 17.],
[ 2., 13., 13., -10., 3.]])
二元函数运用
#二元函数运用
k = np.add(a,b)
k
array([[ 23, 12, 26, 16, 25],
[ 3, 1, 11, 16, -4],
[ 12, 7, 0, 19, 22],
[ 4, 14, 19, -10, 12]])
l
l = np.subtract(a,b)
l
array([[ 5, 8, 8, 14, 9],
[ 3, -13, 9, 0, -12],
[ 12, 3, -2, 5, 12],
[ 0, 12, 7, -10, -6]])
z
z = np.floor_divide(k,l)
z
<ipython-input-22-332b19935c94>:1: RuntimeWarning: divide by zero encountered in floor_divide
z = np.floor_divide(k,l)
array([[ 4, 1, 3, 1, 2],
[ 1, -1, 1, 0, 0],
[ 1, 2, 0, 3, 1],
[ 0, 1, 2, 1, -2]], dtype=int32)
x
x = np.equal(k,l)
x
array([[False, False, False, False, False],
[ True, False, False, False, False],
[ True, False, False, False, False],
[False, False, False, True, False]])
v = (k>=l)
print(type(v))
<class 'numpy.ndarray'>
n = np.max(k)
n
26
总结:聚合函数可以指定行计算或者列计算,默认是计算整体。
m = np.mean(l,axis=0)
m
array([5. , 2.5 , 5.5 , 2.25, 0.75])
p
p = np.argmin(k)
p
18
标签:一元,12,False,二元,17,10,np,array,numpy 来源: https://blog.csdn.net/lsmax/article/details/118048763