Problem 771. Map all the indices of an Array Indices into a Vector giving Index vs Row and Column

Created by Richard Zapor in Community

Create an array of the row and column values for the indices of an array.

This is typically performed using [r c]=ind2sub(size(matrix), index).

The ind2sub output can be vectorized.

Create an index row/col array(irc) where index is the row of the irc array, column 1 is the array row and column 2 is the array column.

m=[0 0; 0 1] has four indices thus producing a four row and two column irc array.

  [1 1
   2 1
   1 2
   2 2]

Index 4's row is irc(4,1)=2 and its col is irc(4,2)=2. The values of m are irrelevant.

Puzzle, and initial tightest solution, inspired by code implemented by Alfonso Nieto-Castanon.

Solution Stats

72.22% Correct | 27.78% Incorrect
Last solution submitted on Jan 24, 2019

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