R3.cxx

// Copyright 2023, UChicago Argonne, LLC
// All Rights Reserved
// Software Name: NEML2 -- the New Engineering material Model Library, version 2
// By: Argonne National Laboratory
// OPEN SOURCE LICENSE (MIT)
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#include "neml2/tensors/R3.h"
#include "neml2/tensors/Scalar.h"
#include "neml2/tensors/Vec.h"
#include "neml2/tensors/R2.h"
 
namespace neml2
{
R3
R3::levi_civita(const torch::TensorOptions & options)
{
  return R3(torch::tensor({{{0, 0, 0}, {0, 0, 1}, {0, -1, 0}},
                           {{0, 0, -1}, {0, 0, 0}, {1, 0, 0}},
                           {{0, 1, 0}, {-1, 0, 0}, {0, 0, 0}}},
                          options),
            0);
}
 
Scalar
R3::operator()(TorchSize i, TorchSize j, TorchSize k) const
{
  return base_index({i, j, k});
}
 
R2
R3::contract_k(const Vec & v) const
{
  neml_assert_batch_broadcastable_dbg(*this, v);
  return R2(torch::einsum("...ijk,...k", {*this, v}), broadcast_batch_dim(*this, v));
}
} // namespace neml2