Christopher Smith
Christopher Smith
polyfuncs has a `viete` function, but it doesn't do a simple expansion of the expression `prod(x + i for i in roots)`. Such a routine could be used to efficiently...
It seems that the exponentiation of polynomials (in Poly form or as Expr) could be improved by using a recursive calculation (see [presentation of J.C.P. Miller's algorithm](https://www.researchgate.net/profile/Hal-Finkel/publication/45928996_The_differential_transformation_method_and_Miller%27s_recurrence/links/0deec52f388af44aba000000/The-differential-transformation-method-and-Millers-recurrence.pdf)) of the power's...
Currently there is no way to get the coefficient of a term of a polynomial raised to a symbolic power. This was raised at this [SO question](https://stackoverflow.com/questions/58776517/expanding-polynomial-with-variable-exponent-in-sympy). This is a...
Compare `sqrt` and `Abs`: ```python >>> sqrt(x+pi).n() 1.77245385090552*(0.318309886183791*x + 1)**0.5 >>> Abs(-sqrt(2)*t - t + 2/(sqrt(2) + 2) + 2*sqrt(2)/(sqrt(2) + 2) + 1).n() Abs(-sqrt(2)*t - t + 2/(sqrt(2) +...
Should something like the following be added to the `solvers`? Discussed [here](https://stackoverflow.com/a/73818901/1089161) and [here](https://stackoverflow.com/a/77928578/1089161). ```python def fixedpoint_Eqs(eq, x=None): """rearrange to give eq in form x = g(x)""" f = eq.free_symbols...
``` >>> x.subs(1/x, y) 1/y >>> cos(x).subs(1/cos(x), y) cos(x)
When solving a system like `[cos(x) - 3/S(5), cos(2*x) - y]` solutions written in terms of trig functions could be simplified better: ```python >>> sol=solve([i.rewrite(exp) for i in [cos(x)-3/S(5),cos(2*x)-y]]); sol...
```python >>> ans = 2*tan(x)/(1 - tan(x)**2) >>> assert (tan(2*x)).equals(ans) is None True >>> tan(2*x).expand(trig=1) == ans True
As mentioned [here](https://github.com/sympy/sympy/issues/13961#issuecomment-2002169859), `bottom_up` is a good way to apply a function recursively to elements in a tree. It does not, however, allow traversal of Python list/tuple. Perhaps a new...
As discussed in 1793, the integration routine works too hard in the sense that it carries along x-independent portions that don't need to be integrated. Branch 1961 at smichr's github...