线性代数向量物理向量_向量/矩阵的对数值打印（元素明智的操作）使用Python的线性代数...

布满荆棘的人生 2023-03-05 05:29 3阅读 0赞

线性代数 向量 物理向量

**Prerequisite:**

**先决条件：**

*  [Defining a Vector][]
    
    [定义向量][Defining a Vector]
 *  [Defining a Matrix][]
    
    [定义矩阵][Defining a Matrix]

Numpy is the library of function that helps to construct or manipulate matrices and vectors. The function ***numpy.log(x)*** is a function used for generating a matrix/vector/variable with the log value of b x (as ***log(x)***). This is an element wise operation where each element in ***numpy.log(x)*** corresponds to the logarithmic of that element in x.

Numpy是一个功能库，可帮助构造或操纵矩阵和向量。 函数***numpy.log(x)***是用于生成对数值为bx的矩阵/向量/变量的函数(如***log(x)*** )。 这是一个元素明智的操作，其中***numpy.log(x)***中的每个元素都对应于x中该元素的对数。

**Syntax:**

**句法：**

numpy.log(x)

**Input parameter(s):**

**输入参数：**

*  x – could be a matrix or vector or a variable.
    
    x –可以是矩阵，向量或变量。

**Return value:**

**返回值：**

A Matrix or vector or a variable of the same dimensions as input x with log(x) values (between -1 and 1) at each entry.

与输入x尺寸相同的矩阵或向量或变量，每个条目的log(x)值在-1和1之间。

**Applications:**

**应用范围：**

1.  Machine Learning
    
    机器学习
2.  Neural Network
    
    神经网络
3.  Geometry
    
    几何
4.  Physics Problems
    
    物理问题

## Python代码可打印矢量/矩阵元素的对数值 **(**Python code to print logarithmic value of vector/matrix elements**)** ##

# Linear Algebra Learning Sequence
    # Element Wise Logarithmic Operation
    
    import numpy as np
    
    # Use of np.array() to define an Vector
    V = np.array([323,.623,823])
    print("The Vector A : ",V)
    
    VV = np.array([[3,63,.78],[.315,32,42]])
    print("\nThe Vector B : \n",VV)
    
    # Using munpy.log() function
    print("\nlog(A) : ", np.log(V))
    print("\nlog(B) : \n", np.log(VV))

**Output:**

**输出：**

The Vector A :  [3.23e+02 6.23e-01 8.23e+02]
    
    The Vector B : 
     [[ 3.    63.     0.78 ]
     [ 0.315 32.    42.   ]]
    
    log(A) :  [ 5.77765232 -0.47320876  6.7129562 ]
    
    log(B) : 
     [[ 1.09861229  4.14313473 -0.24846136]
     [-1.15518264  3.4657359   3.73766962]]

> 翻译自: [https://www.includehelp.com/python/printing-logarithmic-value-of-vector-matrix-element-wise-operation.aspx][https_www.includehelp.com_python_printing-logarithmic-value-of-vector-matrix-element-wise-operation.aspx]

线性代数 向量 物理向量

[Defining a Vector]: https://www.includehelp.com/python/defining-vector-using-numpy.aspx
[Defining a Matrix]: https://www.includehelp.com/python/defining-matrix-using-numpy.aspx
[https_www.includehelp.com_python_printing-logarithmic-value-of-vector-matrix-element-wise-operation.aspx]: https://www.includehelp.com/python/printing-logarithmic-value-of-vector-matrix-element-wise-operation.aspx