python变量_Python变量

python变量

In this tutorial we will know some basics about Python Variable. In our previous tutorial we discussed about Python print function.

在本教程中，我们将了解有关Python变量的一些基础知识。在之前的教程中，我们讨论了有关Python打印功能的信息。

Python变量 (Python Variable)

In your mathematics books, you probably heard about variables. Python Variables are use to store values.

在您的数学书中，您可能听说过变量。 Python变量用于存储值。

When you declare a variable in python, some space regarding the variable is preserved in memory. Then you can access them. If you read our tutorial on Python data types, you should probably know about pythons data type.

当您在python中声明变量时，有关该变量的一些空间将保留在内存中。然后，您可以访问它们。如果您阅读了有关Python数据类型的教程，那么您可能应该了解pythons数据类型。

Python声明变量 (Python declare variable)

In most common programming language like c, c++, java etc, you have to set the datatype of the variable when you declare the variable.

在最常见的编程语言（如c，c ++，java等）中，声明变量时必须设置变量的数据类型。

Python python is flexible about this. You can declare a variable and then the data-type of the variable depends on the data you’re storing into it. See the following example.

Python python对此很灵活。您可以声明一个变量，然后变量的数据类型取决于您存储在其中的数据。请参见以下示例。

# declare a variable
var = 'new variable'print('The type of var is :',type(var))  # the type is strvar = 23.0
print('Now, the type of var is :', type(var))  # the type is float

So you will see the output like this.

这样您将看到这样的输出。

多变量分配 (Multiple Variable Assignment)

In our all these tutorials, you have never seen about these. Well, you saw about single variable value assignment.

在所有这些教程中，您从未见过这些。好了，您看到了有关单个变量值分配的信息。

But you can also assign values to multiple values altogether too. You have to keep the value in the rightmost side.

但是您也可以将值分配给多个值。您必须将值保留在最右边。

This idea is not used because we do not need to use this kind of assignment. But perhaps you project may need this idea and there is nothing wrong to learn new things. However, see the following code to understand multiple variable assignment.

之所以不使用此想法，是因为我们不需要使用这种分配。但是也许您的项目可能需要这个想法，并且学习新事物没有错。但是，请参阅以下代码以了解多变量分配。

# assign multiple variable with the same value
var1 = var2 = var3 = 'init'# print the value of each variable separately
print('Value of var1 :', var1)
print('Now, value of var1 :', var2)
print('Again, value of var1 :', var3)

So, the output of the following code will be

因此，以下代码的输出将是

Value of var1 : init
Now, value of var1 : init
Again, value of var1 : init

关于python变量的一些注意事项 (Some notes about python variable)

Some notes regarding creating a Python variable name is given below.

下面提供了有关创建Python变量名称的一些注意事项。

Python variable names cannot be start with numbersPython变量名称不能以数字开头
It cannot be start with special characters不能以特殊字符开头
Python variable names cannot be same as any python’s pre-defined keywords.Python变量名称不能与任何python的预定义关键字相同。
The variable names should be written in camelCase变量名称应使用camelCase编写

Python打印变量 (Python print variable)

We can use print() function to print the variable to console, as you have seen in above programs.

如上面的程序所示，我们可以使用print（）函数将变量打印到控制台。

Python变量范围 (Python variable scope)

Python variable scope depends on where it’s declared in the program. We have explained python variable scope in more details in python namespace post.

Python变量作用域取决于在程序中声明的位置。我们已经在python名称空间发布中更详细地解释了python变量作用域。

That’s all for Python variable. For any query please use the comment box below.

Python变量就这些了。对于任何查询，请使用下面的评论框。

翻译自: https://www.journaldev.com/15186/python-variable

python变量