Syed's Blog

4 posts · terminal version · RSS · all tags

SQL vs Pandas: The Friendly Rivalry

· data-science

Same questions, two languages. When to let the database do the work, when to pull data into Python, and how to stop downloading 40 million rows to compute one average.

Pandas Tricks That Make You Look Like a Wizard

· data-science

Method chaining, query, assign, groupby with named aggregations and other small habits that turn messy notebooks into readable analysis.

Data Cleaning: The 80% of the Job Nobody Puts on LinkedIn

· data-science

Duplicates, missing values, five spellings of the same city and dates in three formats. The unglamorous work that decides whether your analysis is right.

Feature Engineering Is Where the Magic (and the Pain) Lives

· machine-learning

Fancy algorithms get the headlines, but the features you give them decide most of the result. Practical examples with dates, ratios and categories.