Why arrays are the foundation of fast, memory-lean numeric work: how NumPy's contiguous, single-dtype arrays beat Python lists, how to pick the smallest safe dtype, and how vectorization and broadcasting replace slow loops — all measured on the real NYC taxi data.
Welcome to NumPy for Data Engineering, the second module. Under every fast data tool — pandas included — sits NumPy: contiguous arrays of a single type that the CPU can crunch at C speed. If you want to process data efficiently, this is the layer to understand first.
You’ll start by seeing exactly why NumPy arrays are faster and far smaller than Python lists for numeric data, then learn to choose the smallest safe dtype so your arrays don’t waste memory (and how to avoid the overflow trap when you do). You’ll replace slow Python loops with vectorized array operations and measure the speedup on real trip calculations, and use broadcasting to combine arrays of different shapes without copying. The module closes with a guided project that computes real per-trip metrics — duration, speed, fare-per-mile, tip rate — on the taxi data, vectorized and memory-lean.
Start with Lesson 1, where a Python list and a NumPy array do the same job at very different speeds.
Complete all 5 lessons to finish the NumPy for Data Engineering module.