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Diffstat (limited to 'README.md')
-rw-r--r-- | README.md | 17 |
1 files changed, 9 insertions, 8 deletions
@@ -1,13 +1,13 @@ # Ripser -Copyright © 2015–2016 [Ulrich Bauer]. +Copyright © 2015–2018 [Ulrich Bauer]. ### Description Ripser is a lean C++ code for the computation of Vietoris–Rips persistence barcodes. It can do just this one thing, but does it extremely well. -To see a live demo of Ripser's capabilities, go to [live.ripser.org]. The computation happens inside the browser (using [PNaCl] on Chrome and JavaScript via [Emscripten] on other browsers). +To see a live demo of Ripser's capabilities, go to [live.ripser.org]. The computation happens inside the browser (using [PNaCl] on Chrome and JavaScript via [Emscripten] on other browsers). The main features of Ripser: @@ -26,13 +26,14 @@ Input formats currently supported by Ripser: - [DIPHA] distance matrix data - point cloud data -Ripser's efficiency is based on a few important concepts and principles: +Ripser's efficiency is based on a few important concepts and principles, building on key previous and concurrent developments by other researchers in computational topology: - - Compute persistent *co*homology + - Compute persistent *co*homology (as suggested by [Vin de Silva, Dmitriy Morozov, and Mikael Vejdemo-Johansson](https://doi.org/10.1088/0266-5611/27/12/124003)) - Don't compute information that is never needed - (for the experts: employ the *clearing* optimization, aka *persistence with a twist*) - - Don't store information that can be readily recomputed - - Take obvious shortcuts (*apparent persistence pairs*) + (for the experts: employ the *clearing* optimization, aka *persistence with a twist*, as suggested by [Chao Chen and Michael Kerber](http://www.geometrie.tugraz.at/kerber/kerber_papers/ck-phcwat-11.pdf)) + - Don't store information that can be readily recomputed (in particular, the boundary matrix and the reduced boundary matrix) + - Take computational shortcuts (*apparent* and *emergent persistence pairs*) + - If no threshold is specified, choose the *enclosing radius* as the threshold, from which on homology is guaranteed to be trivial (as suggested by [Greg Henselman-Petrusek](https://github.com/Eetion/Eirene.jl)) ### Version @@ -74,7 +75,7 @@ The input is given either in a file whose name is passed as an argument, or thro - `--format`: use the specified file format for the input. The following formats are supported: - `lower-distance` (default if no format is specified): lower triangular distance matrix; a comma (or whitespace, or other non-numerical character) separated list of the distance matrix entries below the diagonal, sorted lexicographically by row index, then column index - `upper-distance`: upper triangular distance matrix; similar to the previous, but for the entries above the diagonal; suitable for output from the MATLAB functions `pdist` or `seqpdist`, exported to a CSV file - - `distances`: full distance matrix; similar to the above, but for all entries of the distance matrix + - `distance`: full distance matrix; similar to the above, but for all entries of the distance matrix - `dipha`: DIPHA distance matrix as described on the [DIPHA] website - `point-cloud`: point cloud; a comma (or whitespace, or other non-numerical character) separated list of coordinates of the points in some Euclidean space, one point per line - `--dim k`: compute persistent homology up to dimension *k* |