Dictionary in Python is one of the most useful core data structures in Python. Sometimes, you may want to create a dictionary and also maintain the order of items you inserted when you are iterating the keys. Python’s collections module has OrderedDict that lets you create a ordered dictionary. Let us see an example of […]
Python
Pearson and Spearman Correlation in Python
Understanding relationship between two or more variables is at the core of many aspects of data analysis or statistical analysis. Correlation or correlation coefficient captures the association between two variables (in the simplest case), numerically. One of the commonly used correlation measures is Pearson correlation coefficient. Another commonly used correlation measure is Spearman correlation coefficient. […]
Pandas query(): How to Filter Rows of Pandas Dataframe?
Pandas offer many ways to select rows from a dataframe. One of the commonly used approach to filter rows of a dataframe is to use the indexing in multiple ways. For example, one can use label based indexing with loc function. Introducing pandas query() function, Jake VanderPlas nicely explains, While these abstractions are efficient and […]
Pandas 0.25.0 is Here. What is New? Named aggregation, explode() and sparse dataframe
If you are like me, you might have missed that the fantastic Pandas team has released the new version Pandas 0.25.0. As one would expect, there are quite a few new things in Pandas 0.25.0. A couple of new enhancements are around pandas’ groupby aggregation. Here are a few new things that look really interesting. […]
Sparse Matrix Slicing in Python: Rows & Columns with SciPy
Fully updated August 2025: This guide has been refreshed with the latest library versions and tested code examples. Efficiently Slicing Rows and Columns from Sparse Matrices in Python with SciPy When working with large-scale data in fields like machine learning or scientific computing, you’ll often encounter sparse matrices—matrices where the vast majority of elements are […]