The COVID-19 pandemic has resulted in an unparalleled increase in the need for Python coding abilities. To excel in this challenging landscape, it is vital to refine your skills to reduce development time and enhance the efficiency of your code.
This article will cover 22 time-saving tips for coding in Python.
What Makes Python So Exceptional?
In recent years, there has been an impressive increase in adoption of Python among developers, as evidenced by several surveys. It owes this trend to its ability to streamline the work of developers at every stage of software development, from coding to upkeep.
If you’ve only completed a few projects before, the Python code snippets outlined below can serve as practical models for future endeavors. Utilizing these pointers can enhance your programming abilities and lead to prosperous projects in the future.
Top Time-Saving Python Best Practices
These tips and techniques are organized into clear and concise groups based on a few select criteria, such as lists, strings, matrices, and dictionaries.
Lists
Initially, it is advisable to simplify the lists.
Here is an example snippet of code using itertools import.
a = [[1, 2], [3, 4], [5, 6]]
If a is an iterable, then b = list(itertools.chain.from_iterable(a)).
Print b.
Output:
[1, 2, 3, 4, 5, 6]
Secondly, reverse a list.
Here is a snippet of code that reverses a list.a=["10","9","8","7"]
print(a[::-1])
Output:
10
9
8
7
Tip #3: Combine Multiple Inventory Sheets
Here is an example snippet of code using the zip() method.a=['a','b','c','d']
b=['e','f','g','h']
for x, y in zip(a, b):
print(x, y)
Output:a e
b f
c g
d h
Tip #4 involves utilizing “negative indexing lists.”
Here is an example of using negative indexing lists.a = [0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10]
a[-3:-1]
Output:
[8, 9]
Tip #5: Analyzing the Most Common Items in a List
Here is an example snippet of code to determine the most common items in a list.a = [1, 2, 3, 4, 2, 2, 3, 1, 4, 4, 4]
max(set(a), key=a.count)
Output:
4
Strings
Tip #6: Reversing a String
Here is an example of reversing a string.a="python"
print("Reverse is", a[::-1])
Output:
The reversed string is “nohtyp”
Tip #7: Splitting a String in Half
Python is often looked to as the language of the future.b=a.split()
print(b)
Output:['Python', 'is', 'the', 'language', 'of', 'the', 'future']
Tip #8: Showcasing Multiple String Values Simultaneously
Here is an example of showing multiple string values together.print("on"*3 + " off"*2)
Output:"ononon off off"
Tip #9: Combining Multiple Strings into One Single String
Here is an example of combining multiple strings into one single string.a = ["I", "am", "not", "accessible", "at", "this", "time."]
print(" ".join(a))
Output:"I am not accessible at this time."
Tip #10: Discovering Anagrams in Two Words
To check if two words are anagrams of each other, we can use the `Counter` method from the `collections` module in Python. An anagram is a word or phrase formed by rearranging the letters of a different word or phrase. We define the function `is_anagram` which takes two strings as arguments. If the count of characters in both strings is the same, then it is an anagram and returns the string with sorted characters.
For example, print(is_anagram('taste', 'state')) will return True, whereas print(is_anagram('beach', 'peach')) will also return True.
Output:TrueTrue
Matrix
Tip #11: Matrix Transposition Trick
We can transpose a matrix in Python using the built-in `zip()` function. Here is an example:mat = [[8, 9, 10], [11, 12, 13]]
To transpose the above matrix:new_mat = zip(*mat)
Printing the rows in the transposed matrix using a for loop:for row in new_mat:
print(row)
Output:
(8, 11)
(9, 12)
(10, 13)
Operators
Tip #12: Chaining Comparison Operators
We can connect comparison operators in Python by chaining them together. Here’s an example:a = 17
b = 21
c = 11
print(c < a < b)
The output of the above code will be True as 11 is less than 17 and 17 is less than 21.
We can also write it as separate print statements:print(c < a) (c < a)
print(a < b) (a < b)
Output:True
Dictionary
Tip #13: Inverting a Dictionary
To invert a dictionary in Python, we can create a new dictionary where the keys are the original dictionary’s values and the values are the original dictionary’s keys. Here’s an example:dict1 = {'a': 1, 'b': 2, 'c': 3, 'd': 4, 'e': 5, 'f': 6, 'g': 7}
To create a new dictionary `dict2` that is the inversion of `dict1`, we can use the following dictionary comprehension:dict2 = {v: k for k, v in dict1.items()}
Printing `dict2` will give us the inverted dictionary as output.print(dict2)
Output:
1. “1,” 2. “2,” 3. “3,” 4. “4,” 5. “5,” 6. “6,” 7. “7”
Tip #14: Duplicating Keys and Values in a Dictionary
In Python, we can have duplicate keys in a dictionary by creating multiple entries with the same key. Here’s an example:dict1 = {'a': 1, 'b': 2, 'c': 3, 'd': 4, 'e': 5, 'f': 6, 'a': 7}
As you can see, the key `’a’` appears twice in the dictionary with different values. In this case, the last value assigned to the key will be the value that is stored in the dictionary.
To duplicate values in a dictionary, we can simply assign the same value to multiple keys. For example:dict2 = {'a': 1, 'b': 1, 'c': 1, 'd': 2, 'e': 2, 'f': 2}
To print the key-value pairs of a dictionary in a formatted manner, we can use a for loop and the `format()` method. Here’s an example:for k, v in dict1.items():
print('{}: {}'.format(k, v))
Output:
a: 7
b: 2
c: 3
d: 4
e: 5
f: 6
Tip #15: Merging Multiple Dictionaries
To merge two or more dictionaries in Python, we can use the double-asterisk (`**`) notation to unpack the dictionaries into a new dictionary. Here’s an example:x = {'a': 1, 'b': 2}
y = {'b': 3, 'c': 4}
z = {**x, **y}
print(z)
Output:
{‘a’: 1, ‘b’: 3, ‘c’: 4}
Initialisation
Tip #16: Assigning Default Values to Empty Dictionary Keys
In Python, we can set default values for dictionary keys using the `get()` method. If a key does not already exist in the dictionary, we can assign a default value to be returned instead of `None`. Here’s an example:my_dict = {'a': 1, 'b': 2, 'c': 3}
print(my_dict.get('d', 0))
In this example, the key `’d’` does not exist in `my_dict`, so `0` is returned instead of `None`.
To create empty dictionaries, sets, and maps in Python, we can use the following syntax:my_dict = dict()
my_set = set()
my_map = map()
Tip #17: Initializing Numbered Lists
To create a list with a fixed number of elements in Python, we can use the multiplication operator `*`. Here’s an example:list_a = [1] * 1000
list_b = [2] * 1000
In this example, `list_a` will contain 1000 instances of the number 1, and `list_b` will contain 1000 instances of the number 2.
Miscellaneous
Tip #18: Inspecting and Identifying an Object’s Memory Address
In Python, we can use the built-in `sys` module to inspect an object’s memory usage. Here’s an example:import sys
a = 10
print(sys.getsizeof(a))
In this example, we are using `sys.getsizeof()` to print the memory size, in bytes, of the integer variable `a`.
Output:
28
Tip #19: Swapping Variable Values
We can swap the values of two variables in Python using a simple assignment statement. Here’s an example:x, y = 13, 26
x, y = y, x
print(x, y)
In this example, the values of `x` and `y` are swapped using the syntax `x, y = y, x`.
Output:
26 13
Function Mapping
Tip #20: Using the `map()` Function
In a programming competition, it is common to be presented with input data in the form of a string or series of values. For example, we could be given the following input:1234567890
To transform input data from a string to a numerical list in Python, we can use the `map()` function in combination with the `split()` method. Here are the steps:
1. Read the input using the `input()` function.
2. Split the input string into a list of strings using the `split()` method.
3. Convert each string element in the resulting list to an integer using `map()`. The code for this step would be `map(int, input().split())`.
4. Finally, we can convert the resulting `map` object to a list using the `list()` function. The code for this step would be `list(map(int, input().split()))`.
In Python, the `input()` function and the `map()` function are two powerful tools for processing various types of input data. No matter what the data type of the input may be, these functions can be used to read and transform the input into the desired format.
In Python, the `map()` function is a powerful built-in tool that can be used to process and transform input data. Here’s an example:
We can ask the user to input a series of numbers separated by spaces using the `input()` function and the `split()` method. We can then pass the resulting list of string values into the `map()` function, along with the `int()` function to convert the values to integers. The resulting `map` object can be converted to a list by wrapping it in the `list()` function. Here’s the code:numbers = list(map(int, input("Enter numbers separated by spaces:").split()))
print(numbers)
In this example, if we enter the input value `1 2 3 4 5 6 7`, the output will be `[1,2,3,4,5,6,7]`.
The `collections` Module for Managing Data
Tip #21: Merging Lists Together
In Python, the `collections` module provides a simple and efficient solution for removing duplicate elements from a list. This is in contrast to Java’s `HashMap`, which is commonly used for this purpose. Compared to `HashMap`, the `collections` module is generally easier to use and requires less boilerplate code.
If you wish to learn more about popular JavaScript frameworks, you can refer to our blog post at 6 Popular JavaScript Frameworks to Consider in 2022.
One way to remove duplicates from a list in Python is to convert the list to a set using the built-in `set()` function. We can then convert the resulting set back into a list using the `list()` function. Here’s an example:numbers = [1,2,3,4,3,4,5,6,7,8,9]
unique_numbers = list(set(numbers))
print(unique_numbers)
In this example, the output will be `[1,2,3,4,5,6,7,8,9]`. If we have multiple lists that we wish to merge together and remove duplicates from, we can simply append them together using the `+` operator before applying the `set()` and `list()` functions.
In Python, we can merge two or more lists together using the `extend()` method. This method can be used to add the elements of one list to the end of another list. Here’s an example:list1 = [1, 2, 3, 4]
list2 = [5, 6, 7, 8, 9]
list1.extend(list2)
print(list1)
In this example, the output will be a single list containing all of the elements from both lists:
[1, 2, 3, 4, 5, 6, 7, 8, 9]
It is important to note that the `extend()` method modifies the original list in place, and does not create a new list. Therefore, if we run the code `a.extend(b)` when `a` and `b` are defined as separate lists, the resulting list will be stored in `a`, and `b` will be empty.
In Python, we can append a list to the end of another list using the `append()` method. Here’s an example:list1 = [1, 2, 3, 4]
list2 = [5, 6, 7, 8, 9]
list1.append(list2)
print(list1)
In this example, the output will be a single list containing the original elements of `list1`, followed by the list `list2` as a nested list:
[1, 2, 3, 4, [5, 6, 7, 8, 9]]
It is important to note that the `append()` method modifies the original list in place, and does not create a new list. Therefore, if we append `list2` to `list1` when `list1` and `list2` are separate lists, the resulting list will be stored in `list1`, and `list2` will not be affected.
Language Structures
Disadvantage #22: Defining Functions Within Other Functions
In Python, it is considered good practice to write code inside functions whenever possible. Encapsulating code in functions allows for better organization, modularity, and reusability of code. Additionally, functions help to isolate code from the global namespace, reducing the risk of naming conflicts and making it easier to test and debug code.
In Python, we can define a function using the `def` keyword, followed by the name of the function and its parameters (if any). Here’s an example:def main():
if i >= 2 ** 3 and i <= 2 ** 5:
print(x)
main()
In this example, we define a function called `main()` that prints the value of a variable `x` if `i` is between the values of `2**3` and `2**5`. We then call the `main()` function to execute the code.
Compared to the code snippet below, the example code above is considered better due to its use of a function to encapsulate the logic and make it easier to read, test, and modify:
In Python, we can use the `range()` function to generate a sequence of numbers between two values. Here’s an example that prints the value of a variable `x` for any value between `2**3` and `2**5`:for x in range(2**3, 2**5 + 1):
print(x)
In this example, we use a `for` loop to iterate over all values generated by the `range()` function, and print the value of `x` for each iteration.
When it comes to storing local variables in Python, using the CPython implementation is generally considered more efficient than other implementations. This is because CPython uses a stack to store local variables, which is faster than using a dictionary as some other implementations do.
Additional Advice
We have an additional tip to complete this list of great Python tips for becoming a more effective and efficient programmer. Check out this resource for more practical advice on recruiting the top talent for your business.
Concatenating Strings
In Python, you can use the `join()` method to concatenate a list of strings into a single string. Here’s an example code snippet that declares an empty string `str1` and a list of strings `some_list`, and uses the `join()` method to concatenate and print the strings:
str1 = ""
some_list = ["Welcome", "To", "Bonus", "Tips"]
print(str1.join(some_list))
In this example, we first declare an empty string called `str1` by assigning it an empty set of quotes. We then define a list of strings called `some_list` that contains the values to be concatenated. Finally, we use the `join()` method to concatenate the strings from the `some_list` using the separator `str1`, and we print the resulting string. The output of the code would be:WelcomeToBonusTips
Alternatively, you can concatenate a list of strings in Python using the `+` operator. Here’s an example:
some_list = ["Welcome", "To", "Bonus", "Tips"]
str2 = " ".join(some_list)
print(str2)
In this example, we define a list of strings `some_list` that contains the values to be concatenated. We then use the `join()` method to concatenate the strings from the `some_list` using the separator `” “`, and we assign the resulting string to a new variable called `str2`. Finally, we print the `str2` variable, which contains the concatenated string with spaces between the words. The output of the code would be:Welcome To Bonus Tips
In Python, you can concatenate strings by using the `+=` operator to add each string to a variable. Here’s an example:
str1 = ""
some_list = ["Welcome", "To", "Bonus", "Tips"]
for x in some_list:
str1 += x
print(str1)
In this example, we define an empty string `str1` and a list of strings `some_list` that contains the values to be concatenated. We then loop over each string `x` in the `some_list`, and use the `+=` operator to add the value of `x` to `str1`. Finally, we print the concatenated string `str1`. The output of the code would be:WelcomeToBonusTips
By implementing the strategies outlined in this article, you can greatly improve your Python programming skills. Try putting them into practice in your next Python-related project or coding competition, and you will soon notice a significant improvement in both speed and efficiency.
