indexing.h

// Copyright (c) 2020 Chris Richardson
// FEniCS Project
// SPDX-License-Identifier:    MIT
 
#pragma once
 
namespace basix::indexing
{
constexpr int idx(int p) { return p; }
 
constexpr int idx(int p, int q) { return (p + q + 1) * (p + q) / 2 + q; }
 
constexpr int idx(int p, int q, int r)
{
  return (p + q + r) * (p + q + r + 1) * (p + q + r + 2) / 6
         + (q + r) * (q + r + 1) / 2 + r;
}
} // namespace basix::indexing