Odometer.cc

// -*- mode: c++; c-basic-offset:4 -*-
 
// This file is part of libdap, A C++ implementation of the OPeNDAP Data
// Access Protocol.
 
// Copyright (c) 2015 OPeNDAP, Inc.
// Author: James Gallagher <jgallagher@opendap.org>
//
// This library is free software; you can redistribute it and/or
// modify it under the terms of the GNU Lesser General Public
// License as published by the Free Software Foundation; either
// version 2.1 of the License, or (at your option) any later version.
//
// This library is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
// Lesser General Public License for more details.
//
// You should have received a copy of the GNU Lesser General Public
// License along with this library; if not, write to the Free Software
// Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
//
// You can contact OPeNDAP, Inc. at PO Box 112, Saunderstown, RI. 02874-0112.
 
#include "config.h"
 
#include <vector>
 
#include <libdap/Error.h>
 
#include "Odometer.h"
 
using namespace std;
using namespace libdap;
 
namespace functions {
 
// documentation in the header file
unsigned int Odometer::next_safe()
{
    if (d_offset == end()) throw Error("Attempt to move beyond the end of an array in the indexing software.");
 
    // About 3.3 seconds for 10^9 elements
    vector<unsigned int>::reverse_iterator si = d_shape.rbegin();
    for (vector<unsigned int>::reverse_iterator i = d_indices.rbegin(), e = d_indices.rend(); i != e; ++i, ++si) {
        if (++(*i) == *si) {
            *i = 0;
        }
        else {
            break;
        }
    }
 
    return ++d_offset;
}
 
} // namespace function