MatrixGetLength

MatrixGetLength is a function used in matrix and array libraries to query the size of a matrix along a specified dimension. It provides a fast way to retrieve the length of a given axis without inspecting the entire data structure. The exact name and signature can vary by language, but the core concept is consistent: return the length of the requested dimension.

In typical usage, matrixGetLength takes two arguments: a matrix and a dimension indicator. For two-dimensional matrices, dimension 0 commonly refers to the number of rows, and dimension 1 refers to the number of columns. Some libraries allow the dimension to be specified as a string (for example, "rows" or "columns") or as an enumeration value. The function usually returns an integer representing the size of that dimension.

If the dimension is omitted, behavior varies by implementation. Some environments return the total number of elements (rows multiplied by columns), while others require an explicit dimension and may raise an error if omitted.

Examples in pseudo-code:

- nRows = matrixGetLength(A, 0) // number of rows

- nCols = matrixGetLength(A, 1) // number of columns

- total = matrixGetLength(A) // total elements, if supported by the library

Notes and considerations:

- Behavior and supported dimensions vary between libraries; always consult the specific documentation.

- In languages with explicit shape properties (such as shape or GetLength), those built-ins may be preferred for clarity and compatibility.

- MatrixGetLength is most useful when validating dimensions prior to operations or when iterating over matrix rows or columns.