public static Lst <Polynomize.Equation> Substitute(Lst <Polynomize.Equation> eqs, Lst <Subst> substs, Style style)
{
if (eqs is Cons <Polynomize.Equation> cons)
{
Polynomize.Equation eq = cons.head;
Lst <Monomial>[] args = new Lst <Monomial> [eq.args.Length];
for (int i = 0; i < eq.args.Length; i++)
{
args[i] = Substitute(eq.args[i], substs, style);
}
Subst subst = Lookup(eq.var, substs);
if (subst == null)
{
return
(new Cons <Polynomize.Equation>(new Polynomize.Equation(eq.var, eq.op, args, eq.splitOp),
Substitute(cons.tail, substs, style)));
}
else
{
return
(new Cons <Polynomize.Equation>(new Polynomize.Equation(subst.plus, eq.op, args, splitOp: Polynomize.Split.Pos),
new Cons <Polynomize.Equation>(new Polynomize.Equation(subst.minus, eq.op, args, splitOp: Polynomize.Split.Neg),
Substitute(cons.tail, substs, style))));
}
}
else
{
return(Polynomize.Equation.nil);
}
}
public static Polynomize.Equation Rename(Dictionary <Symbol, SpeciesFlow> dict, Polynomize.Equation eq, Style style)
{
Lst <Monomial>[] args = new Lst <Monomial> [eq.args.Length];
for (int i = 0; i < eq.args.Length; i++)
{
args[i] = Rename(dict, eq.args[i], style);
}
if (dict.ContainsKey(eq.var.species) && eq.splitOp != Polynomize.Split.No)
{
throw new Error("Positivize.Rename");
}
SpeciesFlow newVar = dict.ContainsKey(eq.var.species) ? dict[eq.var.species] : eq.var;
return(new Polynomize.Equation(newVar, eq.op, args, eq.splitOp));
}