1. 创造向量数据

import numpy as np//设置宏定义np == numpy
print (np.arange(15))
---结果：[0 1 2 3 4 5 6 7 8 9 10 11 12 13 14]

2.创造矩阵数据

import numpy as np
print (np.arange(15))
a=np.arange(15).reshape(3,5)
---结果：[[0,1,2,3,4],
        [5,6,7,8 ,9], 
        [10, 11, 12, 13, 14]]

3.打印数据包含的元素数量

a,size //a:矩阵定义名称 size：矩阵数据包含元素数量

4.初始化无数据矩阵

内部数据0

 import numpy as np//设置宏定义
 np == np.zeros((3,4))
 ---结果：3X4，数据为0的矩阵

内部数据1

 import numpy as np//设置宏定义
 np.ones((2,3,4),dtype=np.int32)
 ---结果：2X3X4，数据为1的矩阵

5.创造数据自加

    import numpy as np//设置宏定义
    np.arange([10,30,5])//起始值10；终止值<30；p=5
    ---结果array([10,15,20,25])

公式：np.arange([A,C,B]) //A：起始值； B：p值；C:终止值<C

6.随机数据

nump.random-根据数据内容范围确定矩阵（整数）

 import numpy as np//设置宏定义
 np.random.random (2,3)//np.random(2,3)的数据，矩阵2X3
 ---结果：2X3，数据为2-3的矩阵

nump.linspace-根据数据内容范围确定矩阵（数据点）

 import numpy as np//设置宏定义
 from numpy import pi//设置宏定义
 np.linspace(0,2*pi,100)//利用np.linspace设置0-2*pi，取100个数据点

np.sin（np.linspace-根据数据内容范围确定矩阵（数据点+函数应用）===nump.sin

 import numpy as np//设置宏定义
 from numpy import pi//设置宏定义   
 np.sin（np.linspace(0,2*pi,100))//利用np.linspace设置0-2*pi，取100个数据点

numpy.sin

numpy.sin(x, /, out=None, *, where=True, casting=‘same_kind’, order=‘K’, dtype=None, subok=True[, signature, extobj]) = <ufunc ‘sin’>
Trigonometric sine, element-wise.

Parameters:
x : array_like
Angle, in radians (2 \pi rad equals 360 degrees).
out : ndarray, None, or tuple of ndarray and None, optional
A location into which the result is stored. If provided, it must have a shape that the inputs broadcast to. If not provided or None, a freshly-allocated array is returned. A tuple (possible only as a keyword argument) must have length equal to the number of outputs.
where : array_like, optional
Values of True indicate to calculate the ufunc at that position, values of False indicate to leave the value in the output alone.
**kwargs
For other keyword-only arguments, see the ufunc docs.
Returns:
y : array_like
The sine of each element of x. This is a scalar if x is a scalar.
See also
arcsin, sinh, cos

Notes

The sine is one of the fundamental functions of trigonometry (the mathematical study of triangles). Consider a circle of radius 1 centered on the origin. A ray comes in from the +x axis, makes an angle at the origin (measured counter-clockwise from that axis), and departs from the origin. The y coordinate of the outgoing ray’s intersection with the unit circle is the sine of that angle. It ranges from -1 for x=3\pi / 2 to +1 for \pi / 2. The function has zeroes where the angle is a multiple of \pi. Sines of angles between \pi and 2\pi are negative. The numerous properties of the sine and related functions are included in any standard trigonometry text.

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7.Numpy基本的组合运算

初始值为同类型数据

 import numpy as np//设置宏定义
 a=np.array([20,30,40,50])
 b=np.array(4)
 print(a)//结果[20 30 40 50]
 print(b)//结果[0 1 2 3]
 c=a-b
 print(c)//结果[20 29 38 47]
 c=c-1
 print(c)//结果[19 28 37 46]
 b**2
 print(b**2)//结果[0 1 4 9]
 print(a<35)//结果N N T T

初始值为数组同类型数据

 import numpy as np//设置宏定义
 a=np.array([1,1],[0,1])
 b=np.array([2,0],[3,4])
 print (a)//结果1X1的[1 1][0 1]
 print ('--------')//结果--------
 print (b)//结果1X1的[2 0][3 4]
 print ('--------')//结果--------
 print (a*b)//结果1X1的[2 0][0 4]
 print ('--------')//结果--------
 print (a.dot(b))//结果1X1的[5 4][3 4]
 print ('--------')//结果--------
 print (np.dot)//结果1X1的[5 4][3 4]
               //np.dot值数据替换

—未完待续（2018.10.14.18点26分）

numpy库应用03