Other use for "elimination" method
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Other use for "elimination" method
by RyanStorm » Wed May 28, 2014 5:17 am
n/a
Last edited by RyanStorm on Sun Jul 21, 2024 3:03 pm, edited 1 time in total.
- RyanStorm
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Re: Other use for "elimination" method
by eleven » Sun Jun 01, 2014 2:45 pm
RyanStorm,
it would be nice, if you would come with an example (or you have to define, what you are talking about), so i can only guess, what you mean.
I suppose, with a box you mean, what we call a cell here (boxes for us are the 3x3 subgrids).
And what you call "answers" or "options", is probably, what we call candidates.
So if i understood it right, yes, i would call your methods (bivalue) cell forcing chains, as Sudoku Explainer uses them. However there are also some different definitions for forcing chains, e.g. the one in sudopedia seems to want a common number as outcome, and no common elimination. So in the sudopedia definitions probably "nice loop" is the equivalent technique - and in this forum (simple) AIC's (invaded from the Eureka forum). But though both are logically equivalent, they additionally have a strong emphasis on their notations.
Of course you are right, that if both "answers" imply, that another "box" does not contain an "option", you can eliminate it.
[Edit:]
At a second glance, it very depends on, what you are doing in your extra sheets, if the above techniques are equivalent.
If you don't follow a single chain from the choosen answer (A => B => C...), but solve them like having another puzzle, the equivalent would be a forcing net, or dynamic forcing chain (Sudoku Explainer), and would be hard to notate as nice loop or AIC.
You also have to think of situations like, that the chosen answer leads to a contradiction (contradiction chain) or the solution (what now ?).
So, as said, an example would help.
it would be nice, if you would come with an example (or you have to define, what you are talking about), so i can only guess, what you mean.
I suppose, with a box you mean, what we call a cell here (boxes for us are the 3x3 subgrids).
And what you call "answers" or "options", is probably, what we call candidates.
So if i understood it right, yes, i would call your methods (bivalue) cell forcing chains, as Sudoku Explainer uses them. However there are also some different definitions for forcing chains, e.g. the one in sudopedia seems to want a common number as outcome, and no common elimination. So in the sudopedia definitions probably "nice loop" is the equivalent technique - and in this forum (simple) AIC's (invaded from the Eureka forum). But though both are logically equivalent, they additionally have a strong emphasis on their notations.
Of course you are right, that if both "answers" imply, that another "box" does not contain an "option", you can eliminate it.
[Edit:]
At a second glance, it very depends on, what you are doing in your extra sheets, if the above techniques are equivalent.
If you don't follow a single chain from the choosen answer (A => B => C...), but solve them like having another puzzle, the equivalent would be a forcing net, or dynamic forcing chain (Sudoku Explainer), and would be hard to notate as nice loop or AIC.
You also have to think of situations like, that the chosen answer leads to a contradiction (contradiction chain) or the solution (what now ?).
So, as said, an example would help.
- eleven
- Posts: 3173
- Joined: 10 February 2008
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