How to Index Elements in NumPy Arrays?

NumPy is a popular Python library for data science for array, vector, and matrix computations. This puzzle introduces basic indexing of elements in NumPy arrays. Problem Formulation: How to index elements in NumPy arrays? Indexing 1D Arrays with Positive Indices The most simple use of indexing is with the square bracket notation and positive integers: … Read more

How to Calculate the Standard Deviation in NumPy?

Problem Formulation: How to calculate the standard deviation in NumPy? Differentiations: There are many different variants of this problem: Calculate the standard deviation of a 1D array Calculate the standard deviation of a 2D array Calculate the standard deviation of a 3D array Then you can also calculate the standard deviation along an axis: Calculate … Read more

Python HTML Get Parameter

Problem Formulation: How to perform an HTTP get call in Python? Solution: Use Python’s requests library. This is semantically equivalent to issuing an HTTP get call: http://example.com?param_1=value_1&param_2=value_2 In fact, you can obtain this exact URL by using the r.url attribute on the request object: You can find the text response by using the r.text attribute … Read more

How to Switch Keys and Values in a Python Dictionary?

Problem: Given a dictionary in Python; how to switch Keys and Values?  Method 1: Using a for loop   Method 2: Using the zip function Method 3: Using the map and reverse functions Method 4: Using a dictionary comprehension Summary: Use one of the following methods to switch between the keys and values in a dictionary with unique values. … Read more

How to Split a Byte String into Lines?

Problem Formulation: Given a byte string that contains new-line characters ‘\n’. How to split the byte string into a list of lines? Example: You want to transform the byte string b’your\nbyte\nstring’ into the list of byte strings [b’your’, b’byte’, b’string’] using b’\n’ as a newline separator. Given: b’your\nbyte\nstring’ Goal: [b’your’, b’byte’, b’string’] Solution: To split … Read more