Apply for complex valued functions

Application of a complex convolution.

Warning

doxygenfunction: Unable to resolve function “mrcpp::apply” with arguments “None”. Candidate function could not be parsed. Parsing error is Invalid C++ declaration: Expected ‘<’ after ‘template’ [error at 9] template void apply (CompFunction< 3 > &out, DerivativeOperator< 3 > &oper, CompFunction< 3 > &inp, int dir=-1, const ComplexDouble(*metric)[4]) ———^

(

double prec, ComplexObject< FunctionTree<D> > &out, ComplexObject< ConvolutionOperator<D> > &oper, ComplexObject< FunctionTree<D> > &inp, int maxIter, bool absPrec

)