// Copyright (c) 2015-2016, Massachusetts Institute of Technology
// Copyright (c) 2016-2017 Sandia Corporation
// Copyright (c) 2017 NTESS, LLC.

// This file is part of the Compressed Continuous Computation (C3) Library
// Author: Alex A. Gorodetsky 
// Contact: alex@alexgorodetsky.com

// All rights reserved.

// Redistribution and use in source and binary forms, with or without modification, 
// are permitted provided that the following conditions are met:

// 1. Redistributions of source code must retain the above copyright notice, 
//    this list of conditions and the following disclaimer.

// 2. Redistributions in binary form must reproduce the above copyright notice, 
//    this list of conditions and the following disclaimer in the documentation 
//    and/or other materials provided with the distribution.

// 3. Neither the name of the copyright holder nor the names of its contributors 
//    may be used to endorse or promote products derived from this software 
//    without specific prior written permission.

// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" 
// AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 
// IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE 
// DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE 
// FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 
// DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR 
// SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER 
// CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, 
// OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 
// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

//Code








#ifndef TENSORTRAIN_H
#define TENSORTRAIN_H

#include "tensor.h"
#include "linalg.h"

struct tt {
    size_t dim;
    size_t *nvals;
    size_t *ranks;
    struct tensor **cores;
};

void init_tt_alloc(struct tt ** tta, size_t dim, const size_t *);
struct tt * copy_tt(const struct tt *);
struct tt * tt_ones(size_t, const size_t *);
struct tt * tt_x(const double *, size_t, size_t, size_t *);
struct tt * full_to_tt(const struct tensor *, double);
void freett(struct tt *);

double ttelem(struct tt * ttc, size_t * elem);

// useful utilities
void right_ortho_core(struct tt **, size_t);
void right_left_orth(struct tt **);

#endif
