danny wrote:[Catagolue]'s my most frequently used 'parent finder', but I think you can get WLS/JLS to do it.
Yup. In JLS, if you just want to find a simple predecessor, you choose a search size under Edit > Properties, and also set the number of generations to 2 and in the
Tiling/translation tab set the "After the last generation is..." setting to
Unknown.
Then in generation 1, draw all OFF cells (select all, then right-click), then draw the ON cells you want. In generation 0, draw all OFF cells also, then hollow out an area of empty cells where you want to allow either ON or off.
For a challenging search, it's often important to set the search options correctly -- Search > Options > Sorting and Search > Options > Constraints. Maybe the most important detail is to try to start the search from the most difficult point and work outwards from there. If you start the search in an easy corner somewhere with a lot of possibilities, JLS will take enormously longer, or sometimes roughly forever, to get through the entire search. If you start the search in the right place, it will be able to eliminate huge swaths of the search space without having to fill in those easy corners in all possible ways.
Here's a .jdf file that shows a sample setup. Run it and in a second or two it will report 11,902 father patterns for the pattern in question, inside the arbitrary space I defined for Generation 0.
sample-parent-search.jdf.txt
- Sample setup with unnecessarily large area (but you should leave a couple of blank cells around the edges, like the top and bottom here)
- (5.81 KiB) Downloaded 95 times
If you want to actually see the solutions it finds, change the "Pause search after each solution" and/or "Append solutions to file" settings in Search > Options > Processing.