Christopher Smith

heurisch is permuting all generators when trying to find a valid substitution that will lead to a solvable system of equations. This breaks the desired ordering of generators and can...

Plot should plot polygons

2

``` All geometry objects but Polygon are plotted. Here is a way to plot a polygon with a Curve containing a Piecewise function: # plot polygon and piecewise together t...

variable of differentiation returns True from `has_free`

4

I believe both should be False: ```python >>> Derivative(f(x), t).has_free(t) True >>> t in Derivative(f(x), t).free_symbols False ``` Identified [here](https://stackoverflow.com/q/78547166/1089161).

DomainMatrix will modify lists used for its construction -- intended?

10

I am not sure that the mutation of the instantiating lists for a DomainMatrix is intended: ```python >>> l = [1,2] >>> DomainMatrix([l],(1,2),ZZ) DomainMatrix([[1, 2]], (1, 2), ZZ) >>> _[0,0]=42...

There were many observations about what is wrong with using `subs` in the PR [here](https://github.com/sympy/sympy/pull/26935). Something more literal for `heurisch` (and perhaps any internal substitution in SymPy?) might be needed.

make as_base_exp literal, like fraction

9

`as_base_exp` no longer does any introspection, it just returns the literal arguments of the `Pow`, so the return values of `S.Half**x` and `1/2**x` are no longer the same. ```python >>>...

The start of doc/src/modules/solvers/diophantine refers the user to the guide, but clicking that link takes you to the self-same page instead of the guide at https://github.com/sympy/sympy/blob/master/doc/src/guides/solving/solve-diophantine-equation.md

bug in `simplify_logic`

3

Issue identified [at SO](https://stackoverflow.com/questions/78779780/is-sympys-simplify-to-be-used-on-unknown-functions): ```python >>> simplify(Eq(f(1),x*f(2))) Eq(f(1), 0) ``` A potential fix is to move the definition of `variables` out of the `if`-block and remove the initial expression: ```...

[feat] `apply` added as traversal

3

#### References to other Issues or PRs closes #26375 #### Brief description of what is fixed or changed An `apply` function has been added to traversals so aribitrarily nested Python...

make cancel canonical for a given expression

10

#### References to other Issues or PRs fixes #27096 #### Brief description of what is fixed or changed The result of `p.cancel(q, include=False)` should be the same as `P.cancel(Q)` if...