As others have indicated, the Show
From your description, I think you're using Windows, you've saved a Use a command-promptWhen you're looking at the folder window that contains your Python program, hold down shift and right-click anywhere in the white background area of the window. The menu that pops up should contain an entry "Open command window here". (I think this works on Windows Vista and Windows 7.) This will open a command-prompt window that looks something like this:
To run your program, type the following (substituting your script name):
...and press enter. (If you get an error that "python" is not a recognized command, see http://showmedo.com/videotutorials/video?name=960000&fromSeriesID=96 ) When your program finishes running, whether it completes successfully or not, the window will remain open and the command-prompt will appear again for you to type another command. If you want to run your program again, you can press the up arrow to recall the previous command you entered and press enter to run it again, rather than having to type out the file name every time. Use IDLEIDLE is a simple program editor that comes installed with Python. Among other features it can run your programs in a window. Right-click on your Table of Contents
IntroductionUser interaction is an essential part of many programs. The websites and apps that we use every day offer many ways to interact with them, often allowing users to supply their own input in various ways. For programs that run on the command-line, programming languages typically offer a way to prompt the user to supply some typed input. This user-supplied input can then be stored in a variable in the code and used in the program's flow. Python has included this functionality for many years. However, when Python 2 was superseded by Python 3, major changes were made. These included changes to user input functions. This can make it confusing for developers to track down the correct method to use for user input in Python command-line programs. In this article, we will review how to accept user input in Python 2 and Python 3. We will look at what changed in Python 3 and discuss why these changes were made. raw_input() function in Python 2Python 2 included the built-in function The most common way to use this function is to assign its result to a variable, and then perform some actions with that data:
In the third line of the code above, the raw_input() function
prompts the user to type a value and stores that value as a string in the variable
If the user is not instructed that the program is waiting for them to type in an input, they may think the program is hanging or that it crashed. The
In
the above example, we did this in Python 2 without adding an '\n' (end line character) in the printed message, by using the However, this is actually unnecessary because you can perform this task much more easily with an argument in the raw_input() function in Python 2. This argument is a string that is displayed to the user to prompt them for user input, so they are aware they need to input some data. For example:
However, if you have strict formatting requirements for multiple lines of prompting, it can be helpful to use both print statements and the raw_input() argument. input() function in Python 2Python 2 has another built-in function to get user input, the This might seem confusing at first. But, it pretty much that the input() function can receive different data types, such as integers, lists, dictionaries, etc depending on the user's input. Let's look at an example to better understand it:
When the input() function prompts for an input, if the user types the integer 12, the value 12 is stored as an integer in variable
Allowing users to input arbitrary data structures may seem useful at first glance, but it has major issues and has been removed in Python 3. Let's see why... Why was the original input() removed from Python?First, we should clarify that the input() function in Python 2 is completely different from the input() function in Python 3. As we mentioned before, Python 2 included both raw_input() (which always converted the user's input to string datatype) and input() which accepted the datatype provided by the user. Python 3, The main reason why the original functionality of the input() function was removed in Python 3 is for security. The input() function from Python 2 essentially enabled the user to execute raw code, giving the user the power to manipulate code and the inner workings of a program. For example, in Python 2, a user could execute a function from the input() prompt:
Giving the user so much power can be dangerous, and it could be used with malicious intent, and has therefore been removed in Python 3. input() function in Python 3The
Here you can see that input() always returns a string in Python 3 and accepts a string (prompt) argument in the same way as raw_input(). Multi-Line user inputPython 3's input() function (and Python 2's raw_input()) can store only one line of user input at a time. Using the
And it is also wrong to assume that the user knows what the
Here, you first create a list Next, you need to format the user input correctly:
You can then join the lines in the SummaryIn this article, we discussed the various functions you can use in Python to get user input from the command-line. First, you saw how to use the user input functions in Python 2: raw_input() and input(). Then you saw why the functionality for the input() function in Python 2 was removed in Python 3. Next, you saw how to use the input() function in Python 3, which is the same as raw_input() from Python 2. Finally, you saw how you can accept and format multi-line user input with a while loop. Next StepsIf you're interested in learning more about the basics of coding, programming, and software development, check out our Coding Essentials Guidebook for Developers, where we cover the essential languages, concepts, and tools that you'll need to become a professional developer. Thanks and happy coding! We hope you enjoyed this article. If you have any questions or comments, feel free to reach out to . Final NotesWhy is raw_input not defined in Python?Because we are using Python 3. x to run our program, raw_input() does not exist. Both the raw_input() and input() statements are functionally the same. This means we do not need to make any further changes to our code to make our codebase compatible with Python 3.
Does python3 have raw_input ()?The raw_input() function can read a line from the user. This function will return a string by stripping a trailing newline. It was renamed to input() function in Python version 3.0 and above.
How do you fix raw_input is not defined?The NameError: name 'raw_input' is not defined occurs when you try to call the raw_input() function using Python major version 3. You can only use raw_input() in Python 2. To solve this error, replace all instances of raw_input() with the input() function in your program.
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