Pandas¶
Beginner → Intermediate · 6 topics
pandas works with tables — rows and named columns, like a spreadsheet you control with code. In GenAI work you'll use it to load documents, clean data, prepare RAG chunks, compare models and turn LLM logs into reports. It's built on NumPy.
All the pages use one small, realistic dataset — LLM evaluation results:
| model | question | latency_ms | tokens | cost_usd | rating |
|---|---|---|---|---|---|
| gpt-4o-mini | What is RAG? | 820 | 210 | 0.00013 | 5 |
| llama-3.1-8b | What is RAG? | 410 | 190 | 0.00002 | 4 |
| … | … | … | … | … | … |
| # | Topic | Sub-topics |
|---|---|---|
| 1 | Series & DataFrames | Create tables · read CSV/JSON · inspect: head, info, describe · save |
| 2 | Selecting & filtering | Columns · loc / iloc · conditions · isin, str.contains · query · sorting |
| 3 | Cleaning data | Missing values · types · dates · duplicates · text cleanup · new columns |
| 4 | Grouping & aggregation | groupby · named aggregations · transform · value_counts · pivot tables |
| 5 | Combining & reshaping | merge (joins) · concat · melt · pivot · explode |
| 6 | Pandas for GenAI | RAG chunks · token & cost reports · model comparison · JSONL for fine-tuning |
Pandas thinks in columns
Write df["cost"] * 1000, not a loop over rows. Column operations are short, readable and run
at NumPy speed.
Next: Series & DataFrames →