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Python map() and lambda() Use Cases and Examples

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 In Python, map() and lambda functions are often used together for functional programming. Here are some examples to illustrate how they work. Python map and lambda top use cases 1. Using map() with lambda The map() function applies a given function to all items in an iterable (like a list) and returns a map object (which can be converted to a list). Example: Doubling Numbers numbers = [ 1 , 2 , 3 , 4 , 5 ] doubled = list ( map ( lambda x: x * 2 , numbers)) print (doubled) # Output: [2, 4, 6, 8, 10] 2. Using map() to Convert Data Types Example: Converting Strings to Integers string_numbers = [ "1" , "2" , "3" , "4" , "5" ] integers = list ( map ( lambda x: int (x), string_numbers)) print (integers) # Output: [1, 2, 3, 4, 5] 3. Using map() with Multiple Iterables You can also use map() with more than one iterable. The lambda function can take multiple arguments. Example: Adding Two Lists Element-wise list1 = [ 1 , 2 , 3 ]
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Python Syntax Errors Cheat Sheet

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Here's is the Python syntax errors cheat sheet. In Python, you can avoid errors, if you know syntax rules. These are missing semicolons, adding extra commas, and extra spaces. Further Python is case sensitive. So using the wrong identifier also will give error.

Python syntax cheat sheet


Python Syntax Errors Cheat Sheet

Indentation is unique to Python. You cannot find strict indentation in any other programming language. You need to focus on the three areas while writing a Python program. To avoid errors you need to learn indentation rules.

  • Indentation or Syntax Errors
  • Exceptions
  • Handling Exceptions

1: Indentation

If you do not follow the proper order, you will get an error. The details of one block shroud follow in one vertical line.

The sub-block should be inside of that. In if loop, the IF, ELIF, and ELSE should have the same indentation. Not only, but the statement inside of them should also have the same indentation.

Best Examples

Understand these examples a good material on indentation for you.

2: Exceptions


Python raises an exception, when it encounters an error. These are called system errors.

Python has many built-in exceptions. One best example is ZeroDivisionError

More exceptions all list in one place.

3: Handling Exceptions


To handle exception you need two blocks which are Try and Except. Try Block is the block where you can give your code. Except is the Block where your exception message comes here.

Python Syntax Example:

try:
d = int(20)
f = str
g = d + f
except TypeError:
  print('This is TypeError Exception')
else :
  print('No exception happened')

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