Open mkoeppe opened 8 years ago
Description changed:
---
+++
@@ -1,3 +1,16 @@
This is preparation for #18805 - `Add didactical implementation of tableau cutting planes to interactive_simplex_method`
and in fact split out from the larger patch there.
+While preparing this patch, I noticed that the code in current Sage is not able to plot some LPs with irrational data. This appears to be due to a bug in the Sage polyhedron code for RDF data (which InteractiveLP uses when the data are not rational).
+
+```
+ sage: poly = polytopes.regular_polygon(7)
+ sage: lp, x = poly.to_linear_program(solver='InteractiveLP', return_variable=True)
+ sage: lp.set_objective(x[0] + x[1])
+ sage: b = lp.get_backend()
+ sage: P = b.interactive_lp_problem()
+ sage: p = P.plot() ### ERROR
+ sage: p.show()
+```
+The code on this ticket does not fix this; it actually has a different failure mode for this example.
+
If you have found a bug in polyhedron code, please open a ticket to fix it!
Replying to @novoselt:
If you have found a bug in polyhedron code, please open a ticket to fix it!
Could be related to #18220
Description changed:
---
+++
@@ -1,16 +1,6 @@
This is preparation for #18805 - `Add didactical implementation of tableau cutting planes to interactive_simplex_method`
and in fact split out from the larger patch there.
-While preparing this patch, I noticed that the code in current Sage is not able to plot some LPs with irrational data. This appears to be due to a bug in the Sage polyhedron code for RDF data (which InteractiveLP uses when the data are not rational).
-
-```
- sage: poly = polytopes.regular_polygon(7)
- sage: lp, x = poly.to_linear_program(solver='InteractiveLP', return_variable=True)
- sage: lp.set_objective(x[0] + x[1])
- sage: b = lp.get_backend()
- sage: P = b.interactive_lp_problem()
- sage: p = P.plot() ### ERROR
- sage: p.show()
-```
+While preparing this patch, I noticed that the code in current Sage is not able to plot some LPs with irrational data (this is now #21270).
The code on this ticket does not fix this; it actually has a different failure mode for this example.
This is preparation for #18805 -
Add didactical implementation of tableau cutting planes to interactive_simplex_method
and in fact split out from the larger patch there.While preparing this patch, I noticed that the code in current Sage is not able to plot some LPs with irrational data (this is now #21270). The code on this ticket does not fix this; it actually has a different failure mode for this example.
CC: @pgxiao @novoselt
Component: linear programming
Author: Peijun Xiao
Branch/Commit: u/mkoeppe/interactivelpproblem__refactor_plot_method @
aa3fa4b
Issue created by migration from https://trac.sagemath.org/ticket/20570