Python List Comprehension With If/Else (Code Examples)
Use if else inside a Python list comprehension to transform elements, or a trailing if to filter them, with examples combining and nesting both.
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2 Ways To Create A Python List With Identical Elements: One-Liners
How can you create a list with identical elements in it with Python? There are two ways to create a list with identical elements in Python. One method is fairly straightforward and easy to remember, whereas the other involves the itertools library. The one I apply the most in my Python coding is the method that uses the asterisk operator to a list containing the item I want to replicate.…
Read guideHow To Read File Into List With 1 Line Of Code In Python
How do read the contents of a file in Python and insert these lines into a list? Using the built-in function open() and the asterisk operator a file’s contents can easily be translated into a list with the following one-liner: [ open('my file.txt')] . What Does open() Function Do? The built-in open() function has one required parameter and several optional parameters. The required parameter is the location of the file.…
Read guideChange List Elements To Int In Python: 1 Line Of Code
How do you convert a list of strings to a list of integers in Python? And can you do it with one line of code? To convert a list of strings to a list of integers use the built-in map() function if you know the contents of the original list will all convert to integers, otherwise use a lambda function in your map() , or use a list comprehension with…
Read guideHow To Remove File Extension From Path String In Python: One-Liner
How do you remove the file extension from a path in Python? And can you do it using just one line of code? The file extension is generally the last set of characters after the final period in a path string. Removing the file extension helps with trying to either rename the file name or with renaming the file extension. For example, if my full path string to a particular…
Read guideHow To Capitalize First Letter Of Every Word In Python (One-Liner)
How do you capitalize the first letter of each word in a string using Python? To capitalize the first letter of every word in Python using one line of code enter the following: " ".join([x.capitalize() for x in my string.split()]) . Here is an example demonstrating how the code works in the Python REPL: As you can see from the above example the output produces a string with each character…
Read guideHow To Split A String In Half In Python: 1 Line Of Code
How do you split a string into two equal halves using Python? To tackle this exercise you need to know how you’re going to operate on odd numbered string lengths. For example, how would you like your code to operate on the string halve . As it has 5 characters you’re going to have 5 possible solutions: hal and ve OR ha and lve ha, l and ve halve OR…
Read guideFind Duplicates In List: Python One Liner
How do you find all the duplicates from a list in Python? To find all the duplicate elements from a list using Python, use the following list comprehension: The result from the above code will be a list of unique elements representing all the duplicate elements from the original list. Here’s an example of how this looks in your Python console: Get List Of Duplicates What if you want a…
Read guidePython Code To Remove Duplicates From List - 1 Liner
How do you remove duplicates from a list using Python? To remove duplicate elements from a list in Python use a list comprehension to create a new list with no duplicates with this code: [x for idx, x in enumerate(original list) if x not in original list[idx+1:]] Here is an example demonstrating how this code works: As you can see from the example above the result from the list comprehension…
Read guidePython Inline For Loop With If (List Comprehension Examples)
Python inline for loop with if: write a list comprehension, put if after for to filter, or if/else before for to transform elements.
Read guideSort Dict By Value Or Sort Dict By Key In Python: 1 Liners
It can be easy to sort a list, whether a list of strings or even a list of dictionaries, but can you sort a dictionary? One way to sort a dictionary by the values of each key : value pair in Python is to use a dictionary comprehension . Dictionary comprehensions are very similar to list comprehensions and have the following schema: The first expression within the dictionary comprehension, the…
Read guideHow To Create A List With Values: Python Code (Examples, One-Liners, No Imports)
You can construct a list in a certain number of ways as detailed in the Python documentation. The most popular I use the most is by defining my list variables using the [] list square bracket notation, for example as my list = [] . This works well when you want to start a list empty, but what if you want to be able to start with a list so…
Read guideRemove Multiple Items From List By Index: Python (Examples, No Imports, One-Liners)
To remove an individual item from a list in Python you can use either a list method or the del statement, both approaches mutate the original list – meaning the list being operated on changes according to the instruction. To remove multiple items from a list you can use the del statement with the slice operator, or you can use a list comprehension with an if condition to filter the…
Read guidePython: Average Of List Of Numbers - Without Imports [One-Liner]
How do you calculate the simple average of a list of numbers in Python, without needing to import any libraries? Unfortunately, there’s no native average or avg function in Python to easily calculate the average of a list containing just numbers: To calculate the average of a list of numbers in Python, use the sum function and the len function and divide the total sum by the total length of…
Read guideCheck For Word In String: Python 1 Liner
How can you check if a word is found in a string using Python? Recently, I had an issue where I wanted to exclude strings from a list if they contained a certain word. I thought I could use the following common code familiar to most using Python: But the problem ended up being a little more difficult than that. For example, what if you want to exclude the term…
Read guideSort List Of Dictionaries By Key: Python 1 Liner
How can you sort a list of dictionaries by a key contained in each dictionary using Python? Can you do it in 1 line to show off your friends? Of course! To sort a list of dictionaries use the sorted() function with the key parameter set to a lambda function that uses the common key found in each dictionary that you want to sort the list by. Previously I posted…
Read guideReverse Order Of List In Python Without For Loops (Examples, One-Liners, No Imports)
There have been times when after creating a list in Python I’ve wanted to sort a list and then have the list reversed from ascending to descending. To reverse the order of a list in Python use either the .reverse() list method which mutates the original list, or the slice operator technique [::-1] which returns a new list. What are the quickest ways to get this task done? Here are…
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