public SubstExp(Variable @var, Algebraic expr)
{
this.@var = @var;
ArrayList v = new ArrayList();
(new GetExpVars2(v)).SymEval(expr);
this.gcd = Exponential.exp_gcd(v, @var);
if (gcd.Equals(Symbolic.ZERO))
{
t = @var;
}
}
public virtual Algebraic ratsubst(Algebraic expr)
{
if (gcd.Equals(Symbolic.ZERO))
{
return(expr);
}
if (!expr.Depends(@var))
{
return(expr);
}
if (expr is Rational)
{
return(ratsubst((( Rational )expr).nom) / ratsubst((( Rational )expr).den));
}
if (expr is Polynomial && ((Polynomial)expr)._v is FunctionVariable &&
((FunctionVariable)((Polynomial)expr)._v).Name.Equals("exp") &&
((FunctionVariable)((Polynomial)expr)._v).Var is Polynomial &&
((Polynomial)((FunctionVariable)((Polynomial)expr)._v).Var)._v.Equals(@var) &&
((Polynomial)((FunctionVariable)((Polynomial)expr)._v).Var).Degree() == 1 &&
((Polynomial)((FunctionVariable)((Polynomial)expr)._v).Var)[0].Equals(Symbolic.ZERO))
{
Polynomial pexpr = (Polynomial)expr;
int degree = pexpr.Degree();
Algebraic[] a = new Algebraic[degree + 1];
for (int i = 0; i <= degree; i++)
{
Algebraic cf = pexpr[i];
if (cf.Depends(@var))
{
throw new JasymcaException("Rationalize failed: 2");
}
a[i] = cf;
}
return(new Polynomial(t, a));
}
throw new JasymcaException("Could not rationalize " + expr);
}