---- May 12, 2009 (after checkpoint61n)
 fortran code to set-up topology is now part of pkg/exch2, with new parameter
 file "data.exch2". 
 None of the modified src file (from any sub.dir) is necessary (just SIZE.h 
 is enough) and therefore has not been updated. No additional parameter
 is needed (can run without "data.exch2", using the default), except for
 the last case (s176t_8x4) with blank tiles: data.exch2.16_blk 
 An other example with blank-tiles can be foundi in:
  verification/adjusment.cs-32x32x1/input/data.exch2.mpi
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Example of modified src code (from matlab-topology-generator) corresponding
to different tiling of regular CS-32 grid:

- s6t_32x32  :   6 tiles, dimension of each tile: 32 x 32 ( 1x1 tile per face)
- s12t_16x32 :  12 tiles, dimension of each tile: 16 x 32 ( 2x1 tile per face)
- s12t_32x16 :  12 tiles, dimension of each tile: 32 x 16 ( 1x2 tile per face)
- s24t_16x16 :  24 tiles, dimension of each tile: 16 x 16 ( 2x2 tile per face)
- s24t_32x8  :  24 tiles, dimension of each tile: 32 x  8 ( 1x4 tile per face)
- s24t_8x32  :  24 tiles, dimension of each tile:  8 x 32 ( 4x1 tile per face)
- s192t_8x4  : 192 tiles, dimension of each tile:  8 x  4 ( 4x8 tile per face)
- s176t_8x4  : 176 tiles, same as s192t_8x4 with 16 blank-tiles

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