Guided Notes
Aggregations & Math Functions
sum, prod, mean, min/max across axes, cumulative sums, differences, LCM/GCD, and trigonometry.
Summing and averaging
Slide 1 / 5Aggregations reduce many values to fewer:
arr.sum(), arr.mean(), arr.min(), arr.max(), arr.std() np.median(arr), np.percentile(arr, 90)
On 2-D arrays, choose the axis: β’ no axis β one result for the whole array. β’ axis=0 β one result per column. β’ axis=1 β one result per row.
arr.argmax() and arr.argmin() return the position of the largest or smallest value instead of the value itself.