零基础自学python 初学numpy 每日一练 【一个小时的练习】

        函数array()

import numpy as cf
f = cf.array([1,2,3,4,5,6,7,8,9])
c = cf.array([9,8,7,6,5,4,3,2,1])
print(f,type(f))
print(c,type(c))

        函数arange()

import numpy as cf
a = cf.arange(1,2,3)
print(a)

        使用size

import numpy as cf
c = cf.array([[1,2,3],[4,5,6],[7,8,9]])
print(c.size)

        生成随机数函数 random

import numpy as cf
c = cf.random.rand(21)
print(c)

        使用shape

import numpy as cf
c = cf.array([[1,2,3],[4,5,6],[7,8,9],[10,11,12],[13,14,15]])
print(c.shape[0])
print(c.shape[1])
print(c.shape[0])

        练习一

import numpy as cf
a = cf.array([1,2,3,4,5,6,7,8,9])
b = cf.array([9,8,7,6,5,4,3,2,1])
print(a)
print(b)
import numpy as cf
w = cf.array([[1,2,3],[4,5,6],[7,8,9]])
t = cf.array([['array()','numpy','size','add']])
print(w,type(w))
print(t.size)

        练习二

import numpy as cf
c = cf.arange(0,4,1)
h = cf.arange(0,7,1)
print(c)
print(h)
import numpy as cf
x = cf.array([[1,2,3],[4,5,6],[7,8,9]])
x_1 = cf.arange(0,9,1)
x_2 = cf.array([1,2,3,4,5,6,7])
print(x)
print(x.size)
print(x_1.size)
print(x_1)
print(x_2)
print(x_2.size)

        练习三

import numpy as cf
c  = cf.random.rand(9)
c_ = cf.random.randn(9)
c_1 =cf.random.randint(9)
print(c.shape)
print(c_.shape)
print(c_1)
import numpy as cf
c = cf.array(24)
print(c)

        练习四

import numpy as cf
e = cf.array([1,2,3,4,5,6,7,8,9])
e_1 = cf.array([[1,2,3],[4,5,6],[7,8,9]])
e_ = cf.array([[4,5,6],[7,8,9],[9,8,7],[3,2,1]])
print(e.ndim)
print(e_1.ndim)
print(e_.ndim)
import numpy as cf
h = cf.array([9,3,1])
print(h[0])
print(h[1])

        练习五

import numpy as cf
g = cf.array([1,2,3])
print(g[0] + g[1])
import numpy as cf
k = cf.array([[9,3,1,0],[1,3,9,3],[9,3,1,1],[1,3,9,1]])
print(k[0,1])
print(k[0,2])
print(k[2,3])

        练习六

import numpy as cf
c = cf.array([1,2,3], dtype = 'u4')
print(c)
print(c.dtype)
import  numpy as cf
c = cf.array([7,3,1],dtype = 'f2')
print(c)
print(c.dtype)

        练习七

import numpy as cf
c = cf.array([[[0,1,0],[0,1,0]],[[1,0,1],[0,1,0]]])
print(c[0,1,2])
print(c[0,1,0])
import numpy as cf
c = cf.array([[1,2,3],[9,8,7]])
print(c[1,-2])

        练习八

import numpy as cf
c = cf.array([9,7,3,4,1])
print(c[:-1])
print(c[0:-1])
print(c[-4:-1])
print(c[-4:0])
import numpy as cf
c = cf.array([1,2,3,4,7,9])
print(c[0:5:2])
print(c[0:0:1])
print(c[:3:])
print(c[::2])

        练习九

import numpy as cf
c = cf.array(['add()','pop()','form'])
print(c.dtype)
import numpy as cf
c = cf.array([7,9,4,3])
print(c.dtype)
import numpy as cf
c = cf.array([9,7,8],dtype = 'i4')
print(c)