how does solveset handle the assumption system

[chaowen guo]

Hi:

the example

import sympy
energy=sympy.symbols('E',positive=True)
from sympy.assumptions.assume import global_assumptions
global_assumptions.add(sympy.Q.positive(energy-1))
position=sympy.symbols('r',real=True)
momentum=energy-1-sympy.exp(position)
interval=sympy.solveset(momentum,position,sympy.S.Reals)   
print(interval)

the output is:Intersection((-oo, oo), {log(E - 1)})

And then I ask:
sympy.ask(sympy.Q.positive(energy-1))
the output is true

So it seems that solveset totally ignores the global_assumptions. How to tell solveset the global_assumptions, so it can use them to do more simplification?

I also try sympy.refine and sympy.simplify to simplify the final interval, but none of them can simplify interval to just {log(E-1)};

By the way, I want to ask how does the assumption system interact with other part of sympy. I know I can give assumption when I define variables, like real=True,
positive=True. But I can not give relative assumption, like E+1 is positive or A-B is greater than C. I figure out global_assumptions may consider relative
assumption. But how about the other parts of sympy, like solveset, integrate, integrate.transform, simplify? Do they take global_assumptions into consideration?
I know mathematica, maple and maxima all support relative assumption. And they can use the assumptions to do more simplification. Does the assumption system in
sympy act like the same way?

[Aaron Meurer]

solveset ignores assumptions. Instead, you should pass the domain that
you wish to solve over as the domain parameter, like solveset(eq, x,
domain=S.Reals).

Relational assumptions like E+1 require the new assumptions (ask(), Q,
refine()). This is still a work in progress and may not work very well
in every case. Most functions in SymPy only consider the old
assumptions (positive=True, is_positive).

Aaron Meurer

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[chaowen guo]

Well, I want to make sure, does solveset just ignore the assumptions about unknown, or ignore everything?

For example:

solveset(a+x**2,x);

Of course, assumption about x is ignored. How about assumption about a?

[Shekhar Prasad Rajak]

Solveset ignores assumptions for all the symbols. Actually it doesn't check assumptions.