Discover MakerZone

MATLAB and Simulink resources for Arduino, LEGO, and Raspberry Pi

Learn more

Discover what MATLAB® can do for your career.

Opportunities for recent engineering grads.

Apply Today

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

Created by Richard Zapor

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.

 irc=
  [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.

Tags

Problem Group

Solution Statistics

18 correct solutions 9 incorrect solutions
Last solution submitted on Jun 08, 2014