1 import numpy as np 2 3 # ndarray 4 5 ''' 6 # 三种创建方式 7 1、从python的基础数据对象转化 8 2、通过numpy内置的函数生成 9 3、从硬盘（文件）读取数据 10 ''' 11 # 创建方法一 12 a= [1,2,3,4] 13 x1 = np.array(a) 14 print(x1,"\n",type(x1)) 15 16 # 创建方法二 17 x = np.arange(5) 18 print(x,"\n",type(x)) 19 20 # # 创建方法三 21 # date,Open,low = np.loadtxt('..csv',delimiter="\t",skiprows=1,usecols=(1,2,4),unpack=True) 22 # print(date,"\n",Open,"\n",low) 23 24 25 # 常用函数 26 ''' 27 min 最小值 28 max 最大值 29 median 中值 30 mean 均值 31 variance 方差 32 sort 33 ''' 34 35 c = np.random.randint(1,100,10) 36 print(np.sort(c)) 37 print(np.mean(c)) 38 39 40 # 练习 41 ''' 42 使用numpy生成100以内的随机数组 43 将数组存储到文件，再从文件中读取数组 44 对数据进行sort ,max ,min ,mean ,variance 45 ''' 46 47 N1 = np.random.randint(0,100,10) 48 # 将N1 存储到文件中 49 np.savetxt("0002.cvs",N1,fmt = "%d",delimiter=",",header="number") 50 # 从文件中读取数组 51 N2 = np.loadtxt("0002.cvs",delimiter=",",skiprows=1) 52 53 print(np.sort(N2)) 54 print(np.max(N2))