Conditional Counting in Pandas: A Step-by-Step Guide to Population Counts by Country

Creating a New Column in a Smaller DataFrame Based on Conditions Met by Another Larger DataFrame

Modifying Column Values in a Pandas DataFrame Based on Another Column

Conditional Statement for Evaluating and Creating New Columns in Dataframes

Filtering Large Dataframes in R Using Data.Table Package: Efficient Filtering of Cars Purchased within 180 Days

Matching Cells in DataFrames: A Step-by-Step Guide for Efficient Data Manipulation

How to Use dplyr's mutate Function to Perform Conditional Sums in R

Building a Free Version of Your App Without Duplicating the Xcode 4 Project: A Step-by-Step Guide

Using Dplyr to Summarize Ecological Survival Data: A Practical Guide to Complex Data Analysis in R

SQL Conditional Select and Conditionals in the WHERE Clause