Glossary · Phase 0 · Tools
Boolean mask
A list of True and False values, one per row or item, used to keep only the items marked True.
Try it now
Click a column to see the pandas that selects it. Then try Filter rows and Group and summarize: each shows the code and what it gives back. The water filter has no rating yet, which pandas shows as NaN.
Learn it properly
DataFrames with pandas · Load a table, pick rows and columns, and summarize groups in a few lines. About 40 minutes.
Other terms from the same lesson
- DataFrame: A table in pandas: rows of data under named columns, like a spreadsheet you work with in code.
- NaN: Short for "not a number": the value pandas and NumPy use for a missing or undefined number.
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