Python sympy 模块，nsimplify() 实例源码

def test_power():
    """
    Take units to some power.

    """
    from sympy import nsimplify

    pc_cgs = cm_per_pc
    mK_cgs = 1e-3
    u1_dims = mass * length**2 * time**-3 * temperature**4
    u1 = Unit("g * pc**2 * s**-3 * mK**4")

    u2 = u1**2

    assert_true(u2.dimensions == u1_dims**2)
    assert_allclose_units(u2.base_value, (pc_cgs**2 * mK_cgs**4)**2, 1e-12)

    u3 = u1**(-1.0/3)

    assert_true(u3.dimensions == nsimplify(u1_dims**(-1.0/3)))
    assert_allclose_units(u3.base_value, (pc_cgs**2 * mK_cgs**4)**(-1.0/3), 1e-12)

def random_complex_number(a=2, b=-1, c=3, d=1, rational=False):
    """
    Return a random complex number.

    To reduce chance of hitting branch cuts or anything, we guarantee
    b <= Im z <= d, a <= Re z <= c
    """
    A, B = uniform(a, c), uniform(b, d)
    if not rational:
        return A + I*B
    return nsimplify(A, rational=True) + I*nsimplify(B, rational=True)

def writeSbml(self, sbml_speciesReference, sbml_level=Settings.defaultSbmlLevel, sbml_version=Settings.defaultSbmlVersion):
        """ Writes a species reference to  a sbml file """

        sbml_speciesReference.setSpecies(self.__species)
        SbmlObject.writeSbml(self, sbml_speciesReference, sbml_level, sbml_version)

        if sbml_level == 3 and self.__hasId:
            Variable.writeSbml(self, sbml_speciesReference, sbml_level, sbml_version)


        elif not sbml_speciesReference.isModifier():
            if sbml_level == 1:
                t_stoichiometry = nsimplify(self.stoichiometry.getInternalMathFormula())
                if t_stoichiometry.is_Rational and t_stoichiometry.q != 1:

                    sbml_speciesReference.setStoichiometry(int(t_stoichiometry.p))
                    sbml_speciesReference.setDenominator(int(t_stoichiometry.q))

                elif t_stoichiometry != MathFormula.ONE:
                    # print srepr(t_stoichiometry)
                    # t_stoichiometry = self.stoichiometry.getSbmlMathFormula(sbml_level, sbml_version)
                    sbml_speciesReference.setStoichiometry(int(t_stoichiometry))

            else:

                t_stoichiometry = self.stoichiometry.getSbmlMathFormula(sbml_level, sbml_version)

                if t_stoichiometry.getType() == AST_REAL:
                    if t_stoichiometry.getReal() != 1.0 or sbml_level == 3:
                        sbml_speciesReference.setStoichiometry(t_stoichiometry.getReal())

                elif t_stoichiometry.getType() == AST_INTEGER:
                    if t_stoichiometry.getInteger() != 1 or sbml_level == 3:
                        sbml_speciesReference.setStoichiometry(t_stoichiometry.getInteger())

                elif t_stoichiometry.getType() == AST_RATIONAL:
                    sbml_speciesReference.setStoichiometry(t_stoichiometry.getNumerator())
                    sbml_speciesReference.setDenominator(t_stoichiometry.getDenominator())

                else:
                    if sbml_level == 3:
                        if self.__model.listOfVariables.containsSymbol(self.stoichiometry.getInternalMathFormula()):
                            sbml_speciesReference.setId(t_stoichiometry.getName())

                        else:
                            sbml_speciesReference.setStoichiometry(t_stoichiometry)
                    else:
                        sbml_stoichiometry_math = sbml_speciesReference.createStoichiometryMath()
                        sbml_stoichiometry_math.setMath(t_stoichiometry)

            if sbml_level >= 3:
                sbml_speciesReference.setConstant(self.constant)