43 lines
2.3 KiB
Markdown
43 lines
2.3 KiB
Markdown
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---
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title: Python Input Function
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---
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Many a time, in a program we need some input from the user. Taking inputs from the user makes the program feel interactive. In Python 3, to take input from the user we have a function `input()`. If the input function is called, the program flow will be stopped until the user has given an input and has ended the input with the return key. Let's see some examples:
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1. When we just want to take the input:
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# This will just give a prompt without any message
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inp = input()
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 <a href='https://repl.it/CUqX/0' target='_blank' rel='nofollow'>Run Code</a>
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1. To give a prompt with a message:
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prompt_with_message = input('<Your prompt message should appear here>')
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# <Your prompt message should appear here> _
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# The '_' in the output is the prompt
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 <a href='https://repl.it/CUqX/1' target='_blank' rel='nofollow'>Run Code</a>
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3\. When we want to take an integer input:
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number = int(input('Please enter a number: '))
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 <a href='https://repl.it/CUqX/2' target='_blank' rel='nofollow'>Run Code</a>
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If you enter a non integer value then Python will throw an error `ValueError`. **So whenever you use this, please make sure that you catch it too.** Otherwise, your program will stop unexpectedly after the prompt.
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number = int(input('Please enter a number: '))
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# Please enter a number: as
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# Enter a string and it will throw this error
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# ValueError: invalid literal for int() with base 10 'as'
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4\. When we want a string input:
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string = str(input('Please enter a string: '))
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 <a href='https://repl.it/CUqX/3' target='_blank' rel='nofollow'>Run Code</a>
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Though, inputs are stored by default as a string. Using the `str()` function makes it clear to the code-reader that the input is going to be a 'string'. It is a good practice to mention what type of input will be taken beforehand.
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<a href='https://docs.python.org/3/library/functions.html#input' target='_blank' rel='nofollow'>Official Docs</a>
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