`ind2sub`

Converts linear indices to row, column and higher subscripts.

Category: Language Fundamentals > Matrices and Arrays

Syntax

[r, c] = ind2sub(sz, ind)

Subscripts for a matrix of size sz.

[i1, i2, ..., iN] = ind2sub(sz, ind)

One subscript per dimension.

Description

MATLAB stores arrays down the columns, so index 1 to m is the first column of an m-row matrix, and so on. ind2sub undoes that numbering, which is what you need after find or max returned a position in the flattened array. sub2ind is the inverse.

If fewer outputs are requested than the array has dimensions, the last output absorbs the remaining ones.

Input arguments

sz: Size vector of the array, such as [3 4] or size(A).
ind: Linear index (or array of indices) in column-major order.

Output arguments

r, c, ...: Subscript arrays, each the same size as ind.

Example

Back to subscripts

[r, c] = ind2sub([2 3], [1 4 6])
[r, c, p] = ind2sub([2 3 2], 11)

Output

r = 1×3

     1     2     2
c = 1×3

     1     2     3
r = 1
c = 3
p = 2

Notes

An index beyond the array size is not reported as an error in MatLivre.

ind2sub