Create a 1D or 2D stairstep array in Matlab

stairstep_array.m

% (c) Jakob Nikolas Kather 2015
% contact: http://www.kather.me

% aim is to create a 1D-stairstep array, i.e. transform 
% 1 2 3 4 to 
% 1 1 1 2 2 2 3 3 3 4 4 4

matrix = 1:4
newSize = 3
step_matrix = reshape(repmat(matrix,newSize,1),1,[])

% aim is to create a 2D-stairstep array, i.e. transform 
% 1 2
% 3 4
% to
% 1 1 2 2
% 1 1 2 2
% 3 3 4 4
% 3 3 4 4

matrix = reshape(1:4,[],2)'
oldSize = 2
newSize = 4
[xold yold] = meshgrid(linspace(0,1,oldSize),linspace(0,1,oldSize));
[xnew ynew] = meshgrid(linspace(0,1,newSize),linspace(0,1,newSize));
step_matrix = interp2(xold,yold,matrix,xnew,ynew,'nearest')