numpy.where — NumPy v2.3 Manual

numpy.where# numpy.where(condition, [x, y, ]/)# Return elements chosen from x or y depending on condition. Note When only condition is provided, this function is a shorthand for np.asarray(condition).nonzero(). Using nonzero directly should be preferred, as it behaves correctly for subclasses. The rest of this documentation covers only the case where all three arguments are provided. Parameters: c

[wkmy]

条件を満たすインデックスを取り出す(nonzero)，内包表記のif elseと同等の処理が行える．使いこなせると便利．