How do you reduce compound inequalities in sympy? (4 < x

Using sympy solve() or reduce_inequalities() works fine for non compound inequalities like 2 - 6 * x <= -4 but it cannot do compound ones.

Is there a different sympy function or a different import that can solve a compound inequality? I can't seem to find anything in the sympy docs or on Google.

CodePudding user response：

solveset() function can solve both simple and compound inequalities.

For example, to solve the compound inequality (2 - 6x <= -4) AND (3x 1 > 4), you can use the following code:

from sympy import *
x = Symbol('x')

ineq1 = Eq(2 - 6*x, -4)
ineq2 = Eq(3*x   1, 4)

solveset(And(ineq1, ineq2), x)

you can use linsolve() function to solve system of linear equations and inequalities.

linsolve([2 - 6*x - 4, 3*x   1 - 4], x)

CodePudding user response：

As others have mentioned...

4 < x - 8 < 10

is the same as...

4 < x - 8 AND x - 8 < 10

So I'm simply doing...

solve(4 < x - 8)
solve(x - 8 < 10)

and just combining the results. So...

(12 < x) & (x < 18) or (12,18) or 12 < x < 18