% Extracts from array 'data' all records with 'value' in the specified 'column' 

function [subset]=extract(data,column,value)

  np = size(data)(1);
  k = 1;

  for ( i=1:np )
    if ( data(i,column) == value )
      subset(k,:) = data(i,:);
      k = k+1;
    endif
endfor

end