private PolynomialTerm(IndeterminateExpression term)
{
_coefficient = 1;
if (term.IsOne)
{
_indeterminates = default;
_indeterminatesSignature = string.Empty;
GreatestPowerIndeterminate = default;
}
else
{
_indeterminates = new[] { term };
_indeterminatesSignature = _indeterminates.AsList().Single().ToString();
GreatestPowerIndeterminate = term;
}
}
private PolynomialTerm(
double coefficient,
ReadOnlyArray <IndeterminateExpression> indeterminates,
string?signature,
IndeterminateExpression greatestPowerExpression)
{
bool anyIndeterminates = indeterminates.Length > 0;
bool hasSignature = signature != null;
if (coefficient.NumericEquals(0) && anyIndeterminates)
{
throw new ArgumentException(nameof(indeterminates));
}
_coefficient = coefficient;
_indeterminates = indeterminates;
if (anyIndeterminates == hasSignature)
{
_indeterminatesSignature = signature ?? string.Empty;
GreatestPowerIndeterminate = greatestPowerExpression;
}
else
{
_indeterminatesSignature = anyIndeterminates ? string.Join(string.Empty, indeterminates.AsList()) : string.Empty;
GreatestPowerIndeterminate = anyIndeterminates ? FindGreatestPowerIndeterminate(indeterminates.AsList()) : default;
}
}
/*
* Query
*/
internal IEnumerable <VariableTerm> GetIdentityVariableTerms()
{
return(_indeterminates
.AsList()
.Where(i => !i.HasUnaryModifier).Select(i => new VariableTerm(variable: i.Variable, power: i.Power)));
}
/*
* Query
*/
internal Dictionary <char, ushort> GetIdentityVariableTerms()
{
return(_terms.AsList().Select(t => t.GetIdentityVariableTerms())
.AggregateCommonBy(v => v.Variable, vc => vc.Select(v => v.Power).MinDefensive()));
}