Recent changes to feature-requests

distinction between original number and new inputs

ganggang — Sun, 21 Sep 2008 06:48:50 -0000

there should be some distinction between original number and new inputs, including both in record and display, Since user handle them differently.
And this may require some change in sdk file, such as a leading 0 in original number.

Steppable solver

Andrew Barnert — Wed, 19 Dec 2007 12:37:35 -0000

It would be great if there were some interface at the module level to run a single step and get an explanation of what to do next and why:

>>> sudoku.step()
{ algorithm: locked_sets, indices: (vertical, (3,), (1, 7)), values: (1, 2), positions: (1, 7), execute: <function> }

This would do the same thing as solve, but as soon as it would be able to reduce the possibilities on one cell, it would instead return the algorithm, loop indices, and values, together with some kind of callback (or key to an "apply" function, or whatever) that could be used to execute the reduction. (Maybe a generator would be a better design?)

That particular result means that the only values in R3C1 and R3C7 are 1 and 2, and therefore those values can be removed from all other cells in R3. (Obviously this would only be a hit if there were any other cells in R3 containing either 1 or 2.)

This means that pysdk would have to represent, store, load, and print "penciled" cells.

This feature could be used almost trivially to log the steps to a solution (like the answers at brainbashers, except those aren't auto-generated):

def logsolution(self):
while True:
nextstep = self.step()
if not nextstep:
if self.finished():
return
raise Unsolvable
self.log(nextstep)
nextstep.execute()

A GUI hint function is another obvious use. For example, color the 1 and 2 in R3C1 and R3C7 green, and all other 1s and 2s in R3 red, and change the "auto" button to remove all the red ones instead of its usual function of doing all dup removals (see below).

Or a CLI hinter that just logs and applies one step and saves the result:

% pysdk.py -t su1.sdk su2.sdk
Solving one step... locked set 18 in column 1, rows 5, 6

Being able to pass an algorithm or list of algorithms to either step or solve would also be handy. For example, you could verify that a puzzle is solvable without using algorithms that you find annoying. Or solve((duplicate_removal, pinned_square)) (or pysdk -tDP maybe?) to turn 182 trivial steps into one big one, leaving you ready for the next interesting challenge. Or just implement brainbashers' "Auto pencil marks" button.

Fallback solver

Andrew Barnert — Wed, 19 Dec 2007 10:42:30 -0000

It would be nice if, given a sudoku that can't be solved with the known algorithms, pysdk would (maybe optionally, e.g., -f for "force solution"?) revert to some kind of guaranteed solver.

The easiest thing to add would be a dumb backtracker. Once you're stumped, pick the first incomplete position, iterate through all possible values, and run the solver recursively on the result. Any success is an immediate success on the original puzzle (unless you need to detect ambiguous sudokus); failure means that value is ruled out, and you can go to the next one.

If you want, I think I could implement it pretty quickly and submit a patch.

Choose the number of grid to generate for a pdf file

Anonymous — Tue, 17 Jan 2006 15:43:34 -0000

First, thank you very much for your program, I use it
every day :)

I have just one suggestion : it would be great if we
can choose the number of grid to generate into a pdf file.

For example :
"I want to print 8 grid with solutions"
python pythonsudoku.py -P -n 8 -s mysudoku.pdf

This will save a pdf file with 8 grids on the first and
second page (4 grids per page), and the solutions on
the last page.

It will be a nice feature :)

Thank you for your efforts.

other input formats

Anonymous — Tue, 13 Dec 2005 14:54:57 -0000

Hello,

I like your program.

I'd like to have different text styles for the gui.

I imagine an option dlg.

Given Numbers for instance as they are now (black)
For numbers I insert (where I'm sure) for example red and
bold.
For numbers, where I'm not sure (trying out) a
different style.