Solvers

Remarks#

As of version 1.0 of Sympy perhaps the main thing to understand about using its solvers is that ’solveset will take over solve either internally or externally’. At this point solveset should already be used for solving univariate equations and systems of linear equations.

Solving a univariate inequality

>>> from sympy.solvers.inequalities import solve_univariate_inequality
>>> from sympy import var
>>> x=var('x')
>>> solve_univariate_inequality(2*x**2-6>1,x,relational=False)
(-oo, -sqrt(14)/2) U (sqrt(14)/2, oo)

The relational=False parameter simply indicates how the results are to be rendered. The default (relational=True) produces a result like this.

>>> solve_univariate_inequality(2*x**2-6>1,x)
Or(And(-oo < x, x < -sqrt(14)/2), And(sqrt(14)/2 < x, x < oo))

Solving a linear Diophantine equation

[![Sample equation][1]][1]

sympy provides its solution as a Python set of expressions in terms of parametric variables, as shown here in the final line.

>>> from sympy.solvers.diophantine import diophantine
>>> from sympy import var
>>> x,y,z=var('x y z')
>>> diophantine(2*x+3*y-5*z-77)
{(t_0, -9*t_0 - 5*t_1 + 154, -5*t_0 - 3*t_1 + 77)}