samer@4: function X=sbitmap(c,K)
samer@4: % sbitmap - turn sequence of integers into sparse binary bitmap
samer@4: %
samer@4: % sbitmap ::
samer@4: %    Y:[[1,L]->[K]] ~'sequence of L natural numbers in 1..K',
samer@4: %    K:natural      ~'height of array to return'
samer@4: % -> X:[[K,L]->0|1] ~'X(i,j)=1 if Y(j)=i'.
samer@4: %
samer@4: % See also BITMAP
samer@4: 
samer@4: L=length(c);
samer@4: if nargin<2, K=max(c); end
samer@4: X=sparse(c,1:L,1,K,L);