A pattern and its variants

albertteng · Posted: Mon Apr 20, 2009 8:35 am Post subject: A pattern and its variants

Using some skills like rotation, swapping rows,columns,and boxes
or changing digits ,we can alter the original pattern (as a model)
into thousands of mutants,all of them may have quite different
appearance,however they possess equal amounts of givens,and belong
to the same levels of difficulties (so far as I have cheched),strictly we could say they are all the same (Is this true ?),and this will speed up
the creation and setting of sudoku puzzles.
under beneath sudoku (a) is an original pattern ,sudoku (b) is one of
its varients
'-----------
sudoku (a) clues:26 level:very hard
2..9...1.
.....2...
...81467.
3....1.8.
..4.6.5..
...4....3
.23158...
...7.....
.4...9..8

'-----------
sudoku (b) clues:26 level:very hard
1..2....3
...94.671
.......5.
.58...712
........9
.7...9.3.
..6.2.8..
.1...4..7
4......2.

Is there any special terminology in "sudoku field" put labels
on (a) and (b)?

Adak · Posted: Mon Apr 20, 2009 10:59 am Post subject:

Such puzzle grids are called "isomorphically" identical.

Look for threads on "canonicalization" (which is the process of changing a puzzle, into a standard (and of course, there is more than one standard Smile

), puzzle grid.

Swapping bands and chutes, rows and columns within those bands or chutes, rotations, relabeling, etc., are all a part of canonicalizing a grid.

albertteng · Posted: Tue Apr 21, 2009 2:42 am Post subject: Thanks Adak

Adak wrote: