Matrix: Difference between revisions

In the APL [[array model]], a matrix (sometimes "table") is an array with [[rank]] 2. While matrices are named after the objects in [https://en.wikipedia.org/wiki/Linear_algebra linear algebra], which are multiplied using the [[matrix product]], APL matrices do not have to be used in this way: they can store arbitrary data like any other array.

Rank 2 is the smallest rank for which multidimensional array theory offers an advantage over one-dimensional lists. Unlike [[Vector|vectors]], [[Transpose]] on matrices changes the order of data, although there is only one possible transpose so dyadic Transpose is never needed. The [[ravel order]] of a matrix has two possible definitions; APLs choose to keep the rows together (row major order) rather than the columns (column major).