Fast in-memory DataFrame library for datasets that fit in RAM. Use when pandas is too slow but data still fits in memory. Lazy evaluation, parallel execution, Apache Arrow backend. Best for 1-100GB datasets, ETL pipelines, faster pandas replacement. For larger-than-RAM data use dask or vaex.

适用于内存中数据的高速内存DataFrame库，当pandas太慢但数据仍能放入内存时使用。支持惰性求值、并行执行和Apache Arrow后端，最适合1-100GB数据集、ETL管道和更快的pandas替代方案。对于超出内存的数据，请使用dask或vaex。