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#include "cadabra2++/Parser.hh"
#include "cadabra2++/Storage.hh"
#include "cadabra2++/DisplayTerminal.hh"
#include "cadabra2++/algorithms/substitute.hh"
#include "cadabra2++/algorithms/evaluate.hh"
#include "cadabra2++/TerminalStream.hh"
#include "cadabra2++/properties/PartialDerivative.hh"
#include "cadabra2++/properties/Coordinate.hh"
#include <iostream>
#include <sstream>
/// \file simple.cc
/// \ingroup libcadabra
///
/// Sample program to demonstrate the use of Cadabra directly from C++ code.
void test1()
{
// The following few lines are equivalent to entering
//
// {r,t}::Coordinate.
// {m,n}::Indices(values={t,r}, position=free).
// ex:= A_{m} A^{m};
// rl:= A_{t} = 3 + a;
// evaluate(ex, rl);
//
// in the Cadabra notebook.
cadabra::Kernel kernel;
kernel.inject_property(new cadabra::Coordinate(), kernel.ex_from_string("{r,t}"), 0);
kernel.inject_property(new cadabra::Indices(), kernel.ex_from_string("{m,n}"),
kernel.ex_from_string("values={t,r}, position=free"));
auto ex = kernel.ex_from_string("A_{m} A^{m}");
auto rl = kernel.ex_from_string("A_{t} = 3 + a ");
cadabra::evaluate ev(kernel, *ex, *rl);
ev.apply_generic();
// Pretty-printing stream object.
cadabra::TerminalStream ss(kernel, std::cerr);
ss << ex << std::endl;
}
void test2()
{
// The following few lines are equivalent to entering
//
// {m,n,p,q}::Indices(position=free).
// \partial{#}::PartialDerivative;
// ex:= \int{ F_{m n} F^{m n} }{x};
// rl:= F_{m n} = \\partial_{m}{A_{n}} - \\partial_{n}{A_{m}};
// substitute(ex, rl, deep=True);
//
// in the Cadabra notebook.
cadabra::Kernel kernel;
auto ind1 = kernel.ex_from_string("{m,n,p,q}");
auto ind2 = kernel.ex_from_string("position=free");
kernel.inject_property(new cadabra::Indices(), ind1, ind2);
auto pd = kernel.ex_from_string("\\partial{#}");
kernel.inject_property(new cadabra::PartialDerivative(), pd, 0);
auto ex = kernel.ex_from_string("\\int{ F_{m n} F^{m n} }{x}");
auto rl = kernel.ex_from_string("F_{m n} = \\partial_{m}{A_{n}} - \\partial_{n}{A_{m}}");
// Pretty-printing stream object.
cadabra::TerminalStream ss(kernel, std::cerr);
ss << ex << std::endl;
ss << rl << std::endl;
// Apply the 'substitute' algorithm.
cadabra::substitute subs(kernel, *ex, *rl);
subs.apply_generic();
ss << ex << std::endl;
}
int main(int argc, char **argv)
{
test1();
test2();
}
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