ChrisTo check your version in your Python script—for example, to make sure that a user of your Python app uses the correct version—you can use the following commands. To achieve this, simply import the sys module and print the sys.version attribute to your Python shell: Try them in our interactive browser-based Python shell: Exercise: execute … Read more
Key Points: To solve the “IndexError: list index out of range”, avoid do not access a non-existing list index. For example, my_list[5] causes an error for a list with three elements. If you access list elements in a loop, keep in mind that Python uses zero-based indexing: For a list with n elements, the first … Read more
Definition np.cumsum(x): The function computes the cumulative sum of a NumPy array. For an array x with elements [a b c d] the cumulative sum is [a a+b a+b+c a+b+c+d]. Formally, each array element with index i is the sum of all elements with index j<i. numpy.cumsum(a, axis=None, dtype=None, out=None) Arguments: a — Array-like data … Read more
Python is the fastest-growing major programming language in the world. Want to participate as a Python coder and install Python on your Windows machine? Here are the seven steps to install Python on Windows: Visit website “Python Releases for Windows”: https://www.python.org/downloads/windows/ Click link “Download Windows x86-64 executable installer” under “Stable Releases” header. A popup opens. … Read more
The Python built-in list data type is powerful. However, the NumPy array has many advantages over Python lists. What are they? Advantages NumPy Advantages Python Lists Multi-dimensional Slicing Library-Independent Broadcasting Functionality Intuitive Processing Speed Less Complicated Memory Footprint Heterogeneous List Data Allowed Many Convenience Methods Arbitrary Data Shape (Non-Square Matrix) Let’s dive into the most … Read more
Do you want to convert a Python set to a list? Use the list(…) constructor and pass the set object as an argument. For example, to convert a set of strings friends into a list, use the code expression list(friends). Here’s an example code snippet that converts the set to a list using the list(…) … Read more
What are the coolest Python tricks? I’ve compiled this list of the best Python tricks—in reverse order. Without further ado, let’s dive into those crazy one-liner Python features, tricks, and functions: 18. Modifying Iterable Elements 1/2 The function map(func, iter) executes the function func on all elements of the iterable iter. Related article: Which is … Read more
Do you have a list but you want to convert it to a Python set? No problem! Use the set(…) constructor and pass the list object as an argument. For example, if you have a list of strings friends, you can convert it to a set using the call set(friends). Here’s an example code snippet: … Read more
What’s the runtime complexity of various list methods? The following table summarizes the runtime complexity of all list methods. Assume that the length of the data type is defined as n (that is—len(data_type)). You can now categorize the asymptotic complexity of the different complexity functions as follows: Operation Example Complexity Index l[i] O(1) Store l[i] … Read more
In this tutorial, you’ll learn the runtime complexity of different Python operations. Then, you’ll learn how to calculate the complexity of your own function by combining the complexity classes of its constituents. This is called “static analysis” The tutorial is loosely based on (source) but it extends it significantly with more practical examples, interactive snippets, … Read more
A wildly popular operation you’ll find in any (non-trivial) code base is to concatenate lists—but there are multiple methods to accomplish this. Master coders will always choose the right method for the right problem. This tutorial shows you the difference between three methods to concatenate lists: Concatenate two lists with the + operator. For example, … Read more
Everybody knows the print function in Python. It prints a string to the shell–and makes the computation of a Python program explicit to the programmer. But only few coders understand its powerful arguments to format the output. What are they? There are two little-used arguments of the print function in Python. The argument sep indicates … Read more