diff --git a/matlab/colmap_oldformat.m b/matlab/colmap_oldformat.m
new file mode 100644
index 0000000..9fb17b0
--- /dev/null
+++ b/matlab/colmap_oldformat.m
@@ -0,0 +1,40 @@
+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
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