API Reference > geometry-core > ArraysAndInterfaces > IndexedXYCollection > crossProductXAndYIndexIndex crossProductXAndYIndexIndex MethodAbstract Return the cross product of vectors from origin to points at indexA and indexB crossProductXAndYIndexIndex(origin: XAndY, indexA: number, indexB: number): number | undefined Parameter Type Description origin XAndY origin for vector indexA number index of first target within the array indexB number index of second target within the array Returns - number | undefined undefined if either index is out of bounds Defined in core/geometry/src/geometry3d/IndexedXYCollection.ts Line 64 Last Updated: 13 June, 2024