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#include "cadabra2++.hh"
#include <iostream>
using namespace cadabra;
using namespace cadabra::cpplib;
int main(int, char **)
{
Kernel k(true);
pprint_enable_utf8();
//{\mu,\nu}::Indices(vector).
// tr{#}::Trace.
// u^{\mu}::SelfNonCommuting.
// u^{\mu}::ImplicitIndex.
// ex:=tr{A u^{\nu} u^{\mu} u^{\mu} u^{\nu} + B u^{\mu} u^{\mu} u^{\nu}
// u^{\nu}}: meld(_);
// inject_property<SelfNonCommuting>(k, "{A,B,C,D }");
// inject_property<Trace>(k, "tr{#}");
// NTensor broadcast
NTensor t3( { 1.0, 2.0, 3.0 } );
NTensor t432=t3.broadcast( {4,3,2}, 1 );
std::cerr << t432 << std::endl;
// Multiplying two scalar variables which each take
// an array of values leads to an outer product.
auto ex1b = "B*A + A"_ex(k);
NEvaluator ev1b(*ex1b);
ev1b.set_variable(Ex("A"), NTensor({1.0, 2.0, 3.0}));
ev1b.set_variable(Ex("B"), NTensor({0.5, 1.0, 5.0, 10.0}));
// This should give a {3, 4} tensor.
auto res1b = ev1b.evaluate();
std::cout << "B*A + A = " << res1b << "\n\n";
auto ex1 = "B*A + C"_ex(k);
NEvaluator ev1(*ex1);
ev1.set_variable(Ex("A"), NTensor({1.0, 2.0, 3.0}));
ev1.set_variable(Ex("B"), NTensor({0.5, 1.0, 5.0, 10.0}));
ev1.set_variable(Ex("C"), NTensor({1.0, -1.0}));
// This should give a {3, 4, 2} tensor.
auto res1 = ev1.evaluate();
std::cout << "B*A + C = " << res1 << "\n\n";
// Trigonometric functions.
auto ex2 = R"( A + B \cos( C ) )"_ex(k);
std::cout << pprint(k, ex2) << '\n';
NTensor nt2({2,4}, 0.0);
nt2.at({1,2}) = 3.1415;
for(auto& v: nt2.values)
std::cout << v << ", ";
std::cout << "\n\n";
std::cout << nt2 << std::endl;
NEvaluator ev(*ex2);
ev.set_variable(Ex("C"), { 3.0 });
ev.set_variable(Ex("B"), { 2.3 });
ev.set_variable(Ex("A"), { 1.2 });
auto res2 = ev.evaluate();
std::cout << "A + B cos(C) = " << res2 << "\n\n";
// Double trig.
Stopwatch sw;
auto ex3 = R"( \cos(x) \sin(y) )"_ex(k);
NEvaluator ev3(*ex3);
ev3.set_variable(Ex("x"), NTensor::linspace(0.0, 3.14, 1000));
ev3.set_variable(Ex("y"), NTensor::linspace(0.0, 3.14, 1000));
sw.start();
auto res3 = ev3.evaluate();
sw.stop();
std::cout << "cos(x) sin(y) over a 1000x1000 grid took " << sw << "\n\n";
// Array indexing.
NTensor nt({2,4,3}, 0.0);
nt.at({1,2,0}) = 6.2830;
nt.at({0,3,2}) = -6.2830;
std::cout << nt << std::endl;
}
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