On 2014-02-27, Amit Jamadagni <[email protected]> wrote: > Hello, > I have been going through the documentation and have following the > discussion on sage-devel. I have this doubt of how the input for a specific > calculation will be given. For example we have a trefoil knot, then if the > user inputs this we can return back the various invariants or various other > properties. But that is being identified by name, how can we make it more > general. One idea I have in mind is the braid word implementation or can we > use tables as they have used. But I still am unclear on how an user would > input a specific knot. Any help on this would be really great. Thanks.
try out knotscape: here it is patched so that it builds on modern Linux/OSX: https://github.com/dimpase/knotscap (I only tested on OSX 10.6.8, do not forget to modify the knotscape script to spacify the location) There are examples how to enter knots... Dima > > Amit. > > > On Thu, Feb 27, 2014 at 8:14 PM, Dima Pasechnik <[email protected]> wrote: > >> On 2014-02-27, Miguel Angel Marco <[email protected]> wrote: >> > Welcome, >> > >> > i am very happy that you have interest in participating in this project. >> > From what i know, persistent homology does not fit really in the knot >> > theory work (even though it would also be a nice addition). I agree with >> > you that one of the first things we should do is to clarify which >> external >> > software can be used, to wrap it instead of rewriting. Although, it might >> > be tricky, some of this software is not maintained anymore, or has some >> > limitations. So it could be the case that, even if there exists some >> > external software to do the job, rewriting it in sage/cython would be a >> > better option. That's why a part of the work should be to go through this >> > available software and check how well it would fit for our purposes. >> > >> > If you feel that writing the knot/link class is not enough work, i would >> > also suggest to write an interactive knot editor (following the idea of >> the >> > graph editor, although, if possible, i would really like something like >> the >> > knotplot editor) for the notebook. I really don't know much about >> > javascript, so i cannot tell how much work it would take. Anyways, it >> could >> > perfectly be a separate project. >> >> IMHO a good and timely project would be knot recognition, a la >> knotscape. It seems that the only present alternatives to knotscape >> are Mathematica packages. Knotscape also computes polynomial invariants, >> so this >> would be a nice feature to get them properly as polynomials rather >> than as lists of coefficients... >> >> Incorporating parts of knotscape into Sage looks doable, as this is >> plain C code. True that it is old, but this does not make it less >> viable. >> >> Dima >> >> >> >> >> > >> > If you have any further questions, please ask. >> > >> > El jueves, 27 de febrero de 2014 03:44:41 UTC+1, [email protected] >> > escribió: >> >> >> >> Just saw the GSOC announcement - awesome stuff! >> >> >> >> My name is Andrew Silver, I'm an undergraduate mathematics major at the >> >> University of Florida (Gainseville, FL). >> >> I currently do numerical/statistical work in computer vision: I'm >> >> comfortable in C++, familiar with Java, HTML5, Javascript, and recently >> >> Sage/Python. >> >> >> >> This semester I was lucky enough to get into a graduate course in >> >> Computational Topology (Topological Data Analysis), and I'm hooked. >> >> >> >> Why Sage? I compiled Sage as soon as my prof gave us a long hw >> assignment >> >> that involved computing homology of a torus, klein bottle, and the Real >> >> Projective Plane... >> >> ..based on triangulations that had 27x18 boundary matrices we had to get >> >> in smith form... (I actually found a bug in matrices mod 2 that I have a >> >> ticket open for, just got to write up some doctests and it should be >> >> fixed). I used Sage instead of Matlab because I couldn't figure out how >> to >> >> get Matlab to save the u,v matrices - open source is the way to go. >> >> >> >> What do I want to do? I'd love to work on implementing knots/links as >> per >> >> ( >> >> >> https://docs.google.com/document/d/15v7lXZR1U4H2pT21d2fyPduYGb74JAFjkXJ6CWYmYfw/pub#h.6l9ekqoc9br7), >> writing classes, functions, invariants, etc. A potential caveat is how >> >> much we want to "reinvent the wheel" because there are already existing >> >> implementations in other packages for some of these things. >> >> >> >> If there isn't enough work there, I'd also be interested in integrating >> >> Stanford's computational topology tools into Sage ( >> >> http://comptop.stanford.edu/programs/) for persistent homology >> >> calculations. Dr. Carlsson (Stanford) gave a talk at UF this week and >> told >> >> me that the tools are still under development, so it would probably be a >> >> matter of getting permission if the community wants to go this route. >> Or we >> >> could start from scratch. I'm thinking Persistence Diagrams, Barcodes, >> >> witness complexes, etc. >> >> >> >> Other math exposure: >> >> Linear Algebra >> >> Introductory Probability >> >> Calc I - III >> >> Discrete Mathematics >> >> >> >> Why do I want to do this? >> >> If I don't contribute to Sage, I'd be implementing algorithms for my >> >> research anyway. Might as well share them with other people! >> >> >> >> github that I contribute to when I have time: https://github.com. You >> can >> >> reach me by email at [email protected] <javascript:> >> >> >> >> >> >> >> > >> >> -- >> You received this message because you are subscribed to the Google Groups >> "sage-gsoc" group. >> To unsubscribe from this group and stop receiving emails from it, send an >> email to [email protected]. >> To post to this group, send email to [email protected]. >> Visit this group at http://groups.google.com/group/sage-gsoc. >> For more options, visit https://groups.google.com/groups/opt_out. >> > -- You received this message because you are subscribed to the Google Groups "sage-gsoc" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To post to this group, send email to [email protected]. Visit this group at http://groups.google.com/group/sage-gsoc. For more options, visit https://groups.google.com/groups/opt_out.
