function [col] = colmap_oldformat(iscal)
  % [col] = colmap_oldformat(iscal)
  % Create a containers.Map object with particle column order.
  % Input
  %   iscal       scalar written? (number of scalars)
  % Output
  %   col         column map which can be indexed by e.g. col('x')
  
  col = containers.Map('KeyType','char','ValueType','double');
  ioffset = 0;
  col('x')  = ioffset+1;
  col('y')  = ioffset+2;
  col('z')  = ioffset+3;
  col('r')  = ioffset+4;
  col('rho')= ioffset+5;
  col('ax') = ioffset+6;
  col('ay') = ioffset+7;
  col('az') = ioffset+8;
  col('u')  = ioffset+9;
  col('v')  = ioffset+10;
  col('w')  = ioffset+11;
  col('ox') = ioffset+12;
  col('oy') = ioffset+13;
  col('oz') = ioffset+14;
  col('fx') = ioffset+15;
  col('fy') = ioffset+16;
  col('fz') = ioffset+17;
  col('tx') = ioffset+18;
  col('ty') = ioffset+19;
  col('tz') = ioffset+20;
  ioffset = ioffset+20;
  if iscal
    for ii=1:iscal
      col(['s',sprintf('%d',ii)]) = ioffset+1;
      col(['q',sprintf('%d',ii)]) = ioffset+2;
      ioffset = ioffset+2;
    end
  end
  col('id') = ioffset+1;
end