id,summary,reporter,owner,description,type,status,priority,milestone,component,resolution,keywords,cc,merged,author,reviewer,upstream,work_issues,branch,commit,dependencies,stopgaps
20877,"Meta-ticket: Piecewise functions, polyhedral complexes, piecewise functions of several variables, periodic piecewise functions",mkoeppe,,"This is a meta-ticket about piecewise functions.
Fractional part, modulo, ...:
- #9935: Make a symbolic mod function
- #21232: Fractional part function {x}
- #21274: frac(x) immediate simplifications
- #21745: Standardize modulo operator % on real numbers (step 1)
- #21747: Standardize modulo operator % on real numbers (step 2)
- #21748: change the mod method of rationals
Piecewise functions of 1 variable:
- #1773: piecewise functions and integration / arithmetic do not play well together
- #8603: Partial sums are off for Fourier series of piecewise functions
- #11225: improve piecewise plotting
- #6895: Detect discontinuities when plotting the ceil function
- #10597: Riemann sums, added trapezoid option
- #21215: Periodic piecewise functions
- #21412: Convert piecewise functions to SymPy
- #21618: plot in piecewise regression (?)
- #21709: Categories for piecewise functions
`RealSet`s, underlying the current implementation of `piecewise`:
- #16063: Unify the classes `RealSet` and `UnionOfIntervals`
- #21249: `RealSet`s fail their `TestSuite`: `_test_category`, `_test_pickling`
- #21242: Allow initializing `RealSet` from `RealInterval` or `RBF` elements (dup: #17791)
- #21243: `RealSet`: add `closure` and `interior` methods
- #21277: `sage_input` for `RealSet` and `piecewise`
- #30832: Connect `RealSet` to `sage.manifolds`
As a generalization, this meta-ticket will implement piecewise functions of several real variables.
The pieces are polyhedral complexes (not necessarily triangulations) or more generally polyhedral dissections (i.e., not necessarily face-to-face).
In my application, the functions will be piecewise linear, possibly discontinuous; but the implementation should be general enough for splines.
- #31748 PolyhedralComplex
- #26512 Piecewise linear functions of several variables
Discussion welcome, in particular in regard to how this code should interact with the existing classes for abstract complexes (CW complexes) and `PointConfiguration`.
- #20878: `PointConfiguration`: Add `plot` method
- #20879: Expose PPL's Not-Necessarily-Closed Polyhedra using Sage Polyhedra -- could play the same role as half-open intervals do in the context of the new piecewise functions.
- #22710: Meta-ticket: polymake
- #24943: Interface to polymake's polyhedral complexes
- #21151: Update TOPCOM to 0.17.7, disable outdated libsoplex support
- #10777: Implement `CombinatorialPolyhedron`
- #18197: Add CGAL package
General piecewise functions:
- #23923: Interface cases function with `SymPy`'s piecewise
- #20191: implement `SymPy` `Piecewise` equivalent
- #21412: Convert piecewise functions to `SymPy`
",task,new,major,sage-9.4,geometry,,piecewise,tscrim rws vbraun vdelecroix jhpalmieri kcrisman paulmasson tmonteil moritz jipilab,,,,N/A,,,,,