Adds IsZero, IsConstant

Author: tturocy

src/solvers/enumpoly/poly.cc

@@ -112,15 +112,13 @@ Array<Monomial<T>> Polynomial<T>::Mult(const Array<Monomial<T>> &p_one,
 
 template <class T> Polynomial<T> Polynomial<T>::DivideByPolynomial(const Polynomial &den) const
 {
-  const Polynomial zero(m_space, static_cast<T>(0));
-
-  if (den == zero) {
+  if (den.IsZero()) {
     throw ZeroDivideException();
   }
 
   // assumes exact divisibility!
-  Polynomial<T> result(m_space);
-  if (*this == zero) {
+  Polynomial result(m_space);
+  if (IsZero()) {
     return result;
   }
 
@@ -134,7 +132,7 @@ template <class T> Polynomial<T> Polynomial<T>::DivideByPolynomial(const Polynom
   }
 
   Polynomial remainder(*this);
-  while (remainder != zero) {
+  while (!remainder.IsZero()) {
     const int deg_rem = remainder.DegreeOfVar(last);
     const int deg_den = den.DegreeOfVar(last);
 

src/solvers/enumpoly/poly.h

@@ -34,6 +34,7 @@ class VariableSpace {
     int number{0};
   };
 
+  VariableSpace() = delete;
   explicit VariableSpace(size_t nvars)
   {
     for (size_t i = 1; i <= nvars; i++) {
@@ -370,6 +371,11 @@ template <class T> class Polynomial {
     });
   }
   [[nodiscard]] const Array<Monomial<T>> &GetTerms() const noexcept { return m_terms; }
+  bool IsZero() const noexcept { return m_terms.empty(); }
+  bool IsConstant() const noexcept
+  {
+    return m_terms.size() == 1 && m_terms.front().TotalDegree() == 0;
+  }
 
   Polynomial LeadingCoefficient(int varnumber) const;
   T NumLeadCoeff() const