Thank you! The Turbot Fish is a type of X-Chain. Take a look at X-Chains at some point. Sorry for saying "Turbo Fish" instead of "Turbot Fish". In New Jersey, a Turbot fish is called a Fluke.
Excellent tutorial on turbot fish. I encountered a puzzle in which the hint was a turbot fish today but I didn’t know what it was. Thank you very much for the explanation. I like the various examples too.
Amazing playlist! I watched each of your videos from #1 to this one, and I am stuck here:) When you say 'this is not a valid turbot fish pattern' , do you mean 'it is a turbot fish pattern, but there is nothing to kill'?
Sorry for the mispronunciation of the word "turbot". As I've said in the posts below where I live it's called a "fluke" or "summer flounder". Tell me which mark in the video you are referring to and I will take a look. Just so you know, a Turbot Fish pattern is an X-Chain with four nodes.
Instead of going through every single permutation, the best way to find a turbot fish is to actually start with a pair of candidate that is in the same box that do not share the same row or column (diagonal to each other) This is because the turbot fish always start or end with a strong link within a box! :)
I agree. As you probably know, the Turbot fish is X-Chain with exactly 4 cells and 3 links. I'm working on a video now for an updated X-Chain search algorithm very similar to what you are saying. In the new video, after you identify all the cells participating in Either-Or links (2 cells in the same row or column house), I state in the video to use each of these cells as a potential starting point for the chaining sequence. Then, after the first Strong-Link in the chain, you look for pairs of Weak-Link following by Strong-Link. Each time you check if the starting cell or ending cell kill any candidates based on the chaining colors. This new X-Chain algorithm will of course work for finding Turbot Fish. Here's another thing you might find really interesting. I was practicing on some puzzles and I found a really interesting Turbot Fish which turned out to be a Nice Loop: www.reddit.com/r/sudoku/comments/on9koi/found_my_first_nice_loop_in_the_wild/ I plan to do a video featuring this puzzle because I think it's a great introduction into Nice Loops which are usually not single digit patterns. I'm also looking at doing a short video on the Empty Rectangle which is similar to the Turbot fish except one of the nodes of the chaining sequence is a group-node with a Group-Link. I'm beefing up the chaining technique videos because my plan is to do some videos on Nice Loops and AICs by the end of the year.
I seem to have a speech impediment where I say Turbo fish when I mean to say Turbot fish with a T sound at the end. I don't how this happened! There are a lot more videos on other topics I want to do so I think I going to let the "turbo fish" stand as it is. I should probably redo it and start saying Turbot correctly. Please accept my apologies for butchering the language.
At the 3:50 mark in the video four cells are highlighted. The comment is "this is not a valid Turbot Fish pattern". Someone posted me a question why? The reason is the kill zone for these four cells would be the cell R3C5. The problem with cell R3C5 is it is being shared by the first, second, and fourth cell of the pattern currently highlighted. The pattern is only valid when the kill zone is formed by the intersection of the first and fourth cells only. Only the first and last cells in the pattern can be shared with the kill zone cell for this to be valid.
Yes. Turbot Fish is just an X-Chain. When I do X-Chains I just start out with first cell being false in my head. I then traverse to the puzzle seeing if I end up at a place where the last cell in the sequence forms a kill-zone with the first cell. Your sequence works just as well as the one in the video. Here's the tutorial I did on X-Chains: ua-cam.com/video/GRAhOv4L1E8/v-deo.html Here's another video that is useful: ua-cam.com/video/cVwV3MXXx5c/v-deo.html An Empty Rectangle is just an X-Chain where one of the links is a "Group Link" in the chaining sequence. At some point I am planning to do a quick video on X-Chains with a more refined search algorithm. I am also thinking of doing a video on X-Chain variants. Anyway, good catch with your observation!
This is a good explanation
Thank you! The Turbot Fish is a type of X-Chain. Take a look at X-Chains at some point. Sorry for saying "Turbo Fish" instead of "Turbot Fish". In New Jersey, a Turbot fish is called a Fluke.
Excellent tutorial on turbot fish. I encountered a puzzle in which the hint was a turbot fish today but I didn’t know what it was. Thank you very much for the explanation. I like the various examples too.
Thanks for the nice comment!
Amazing playlist! I watched each of your videos from #1 to this one, and I am stuck here:) When you say 'this is not a valid turbot fish pattern' , do you mean 'it is a turbot fish pattern, but there is nothing to kill'?
Sorry for the mispronunciation of the word "turbot". As I've said in the posts below where I live it's called a "fluke" or "summer flounder". Tell me which mark in the video you are referring to and I will take a look. Just so you know, a Turbot Fish pattern is an X-Chain with four nodes.
Instead of going through every single permutation, the best way to find a turbot fish is to actually start with a pair of candidate that is in the same box that do not share the same row or column (diagonal to each other)
This is because the turbot fish always start or end with a strong link within a box! :)
I agree. As you probably know, the Turbot fish is X-Chain with exactly 4 cells and 3 links. I'm working on a video now for an updated X-Chain search algorithm very similar to what you are saying. In the new video, after you identify all the cells participating in Either-Or links (2 cells in the same row or column house), I state in the video to use each of these cells as a potential starting point for the chaining sequence. Then, after the first Strong-Link in the chain, you look for pairs of Weak-Link following by Strong-Link. Each time you check if the starting cell or ending cell kill any candidates based on the chaining colors. This new X-Chain algorithm will of course work for finding Turbot Fish.
Here's another thing you might find really interesting. I was practicing on some puzzles and I found a really interesting Turbot Fish which turned out to be a Nice Loop:
www.reddit.com/r/sudoku/comments/on9koi/found_my_first_nice_loop_in_the_wild/
I plan to do a video featuring this puzzle because I think it's a great introduction into Nice Loops which are usually not single digit patterns.
I'm also looking at doing a short video on the Empty Rectangle which is similar to the Turbot fish except one of the nodes of the chaining sequence is a group-node with a Group-Link. I'm beefing up the chaining technique videos because my plan is to do some videos on Nice Loops and AICs by the end of the year.
I seem to have a speech impediment where I say Turbo fish when I mean to say Turbot fish with a T sound at the end. I don't how this happened! There are a lot more videos on other topics I want to do so I think I going to let the "turbo fish" stand as it is. I should probably redo it and start saying Turbot correctly. Please accept my apologies for butchering the language.
At the 3:50 mark in the video four cells are highlighted. The comment is "this is not a valid Turbot Fish pattern". Someone posted me a question why? The reason is the kill zone for these four cells would be the cell R3C5. The problem with cell R3C5 is it is being shared by the first, second, and fourth cell of the pattern currently highlighted. The pattern is only valid when the kill zone is formed by the intersection of the first and fourth cells only. Only the first and last cells in the pattern can be shared with the kill zone cell for this to be valid.
Where I live the Turbot Fish is known as a Fluke or Summer Flounder.
At 08:01 I think that there is another turbot fish alongside the one shown. R2C9 - R2C2 - R6C2 - R5C1 leads to the elimination of 2 in R5C9.
Yes it does! Nice catch!
For the example at 7:26, wouldn't the chaining sequence R4C9 -> R8C9 -> R8C1 -> R9C3 lead to the elimination of the 4 in R4C3 as well? TIA
Yes. Turbot Fish is just an X-Chain. When I do X-Chains I just start out with first cell being false in my head. I then traverse to the puzzle seeing if I end up at a place where the last cell in the sequence forms a kill-zone with the first cell. Your sequence works just as well as the one in the video. Here's the tutorial I did on X-Chains:
ua-cam.com/video/GRAhOv4L1E8/v-deo.html
Here's another video that is useful:
ua-cam.com/video/cVwV3MXXx5c/v-deo.html
An Empty Rectangle is just an X-Chain where one of the links is a "Group Link" in the chaining sequence. At some point I am planning to do a quick video on X-Chains with a more refined search algorithm. I am also thinking of doing a video on X-Chain variants. Anyway, good catch with your observation!
Thnk u so much!!!
You are very welcome!!