Using the C Math Library

Overview 

A one-dimensional subscript contains a single index. When you use the MATLAB C Math Library to perform one-dimensional indexing, you pass mlfIndexRef() a pointer to one array that represents the index. The index array can contain a scalar, vector, matrix, or the return from a call to the mlfCreateColonIndex() function.

The size and shape of the one-dimensional index determine the size and shape of the result; the size of the result is exactly equal to the size of the one-dimensional subscript. For example, a one-dimensional row vector index produces a one-dimensional row vector result. Given the matrix A, the expression A([1 5 8]) produces the row-vector [ 1 5 8 ]. To view the definition of matrix A, see Assumptions for the Code Examples.

To apply a one-dimensional subscript to an N-dimensional array, you need to know how to go from the one-dimensional index value to a location inside the array. See Array Storage for complete details on how MATLAB counts one dimensionally through arrays of N dimensions.

Note    The range for a one-dimensional index depends on the size of the array. For a given array A, it ranges from 1, the first element of the array, to prod(size(A)), the last element in an N-dimensional array. Contrast this range with the two ranges for a two-dimensional index where the row value varies from 1 to M, and the column value from 1 to N.

One-Dimensional Indexing

Selecting a Single Element