sub2ind

Convert N-dimensional subscripts to a single linear index.

Syntax

IND = sub2ind(siz, I1, I2, ...)

Description

Given a size vector siz and one subscript per dimension (I1, I2, …), returns the corresponding 1-based linear (column-major) index. Useful for converting (row, col) or (i, j, k) references into a single index suitable for vector-style indexing.

MathJet’s implementation accepts only scalar subscripts (one index value per dimension). The MATLAB-style array form — passing matched arrays of subscripts — is not yet supported.

Examples

sub2ind([3 4], 2, 3)     % 8   (row 2, col 3 of a 3×4 matrix)
A = magic(3); A(sub2ind([3 3], 2, 3))  % same as A(2,3)

See also

• ind2sub — Convert a linear index to N-dimensional subscripts.
• size — Sizes along all dimensions, or along one specific dimension.