5 ms·

Curve Matcher

55 points by chanind 8y ago

eximius 8y ago
Very cool. Any idea what you'd use it for?
- chanind 8y ago
  The original motivation was for doing Chinese character stroke quizzes in Hanzi Writer [https://chanind.github.io/hanzi-writer https://chanind.github.io/hanzi-writer]. Beyond that I'm not too sure, but hopefully it's useful for somebody :)
  - vespakoen 8y ago
    Perhaps this could be used for "curve fitting" [0]? (used in CAM software to optimise CNC toolpaths) [0] https://en.wikipedia.org/wiki/Curve_fitting https://en.wikipedia.org/wiki/Curve_fitting
- Schweigi 8y ago
  It can be used to detect patterns in signal data. For example to detect patterns like Cups/Handle [1] patterns in stock data. [1] https://www.investopedia.com/terms/c/cupandhandle.asp https://www.investopedia.com/terms/c/cupandhandle.asp
  - deleted 8y ago
    [deleted]
mkl 8y ago
This looks neat! I found the Hanzi Writer demo, but you might want to put some (static) examples in the ReadMe, to explain exactly what the library does.
- chanind 8y ago
  Good call! I just added an image showing 2 curves and their similarity scores to the readme.
wanderfowl 8y ago
Out of curiosity, how is this better than, for instance, using B-splines or some other smoothing spline to fit a given chunk of data? I'm not being snarky, I'm just trying to get my head around the use cases for this.
- chanind 8y ago
  The goal of this library isn't to fit data, but rather to determine if 2 curves have similar shape to each other. So, for instance, if want to determine if a hand-drawn curve has a similar shape to the letter "S" you could use this library to find a similarity score between the curves.
  - wanderfowl 8y ago
    Ahh, I see. Interesting.
foxes 8y ago
Reminds me of some interesting papers that are related to this topic, off the top of my head check out [0-1]. Perhaps relative geodesics is a key word to search. If you picture curves as made out of some sort of pliable material, you can ask how much energy does it take to deform one curve into another. [0] https://arxiv.org/pdf/1305.3572.pdf https://arxiv.org/pdf/1305.3572.pdf [1] https://royalsocietypublishing.org/doi/abs/10.1098/rspa.2016.0619 https://royalsocietypublishing.org/doi/abs/10.1098/rspa.2016...

Curve Matcher

55 points by chanind 8y ago

eximius 8y ago

Very cool. Any idea what you'd use it for?

chanind 8y ago
The original motivation was for doing Chinese character stroke quizzes in Hanzi Writer [https://chanind.github.io/hanzi-writer https://chanind.github.io/hanzi-writer]. Beyond that I'm not too sure, but hopefully it's useful for somebody :)
- vespakoen 8y ago
  Perhaps this could be used for "curve fitting" [0]? (used in CAM software to optimise CNC toolpaths) [0] https://en.wikipedia.org/wiki/Curve_fitting https://en.wikipedia.org/wiki/Curve_fitting
Schweigi 8y ago
It can be used to detect patterns in signal data. For example to detect patterns like Cups/Handle [1] patterns in stock data. [1] https://www.investopedia.com/terms/c/cupandhandle.asp https://www.investopedia.com/terms/c/cupandhandle.asp
- deleted 8y ago
  [deleted]

mkl 8y ago

This looks neat! I found the Hanzi Writer demo, but you might want to put some (static) examples in the ReadMe, to explain exactly what the library does.

chanind 8y ago
Good call! I just added an image showing 2 curves and their similarity scores to the readme.

wanderfowl 8y ago

Out of curiosity, how is this better than, for instance, using B-splines or some other smoothing spline to fit a given chunk of data? I'm not being snarky, I'm just trying to get my head around the use cases for this.

chanind 8y ago
The goal of this library isn't to fit data, but rather to determine if 2 curves have similar shape to each other. So, for instance, if want to determine if a hand-drawn curve has a similar shape to the letter "S" you could use this library to find a similarity score between the curves.
- wanderfowl 8y ago
  Ahh, I see. Interesting.

foxes 8y ago

Reminds me of some interesting papers that are related to this topic, off the top of my head check out [0-1]. Perhaps relative geodesics is a key word to search. If you picture curves as made out of some sort of pliable material, you can ask how much energy does it take to deform one curve into another. [0] https://arxiv.org/pdf/1305.3572.pdf https://arxiv.org/pdf/1305.3572.pdf [1] https://royalsocietypublishing.org/doi/abs/10.1098/rspa.2016.0619 https://royalsocietypublishing.org/doi/abs/10.1098/rspa.2016...