protected override Expression TransformFunction(FunctionExpression functionExpression)
{
DifferentiationRule rule;
if (_rules.TryGetValue(functionExpression.Function, out rule))
{
return(rule(this, functionExpression));
}
UserFunction userFunction = functionExpression.Function as UserFunction;
if (userFunction != null)
{
VariableValuePair[] values = userFunction.Arguments.
Zip(functionExpression, (variable, value) => new VariableValuePair(variable, value)).
ToArray();
SubstituteTransformation transformation = new SubstituteTransformation(values);
return(Transform(transformation.Transform(userFunction.Expression)));
}
return(functionExpression.Differentiate(_variable));
}