include/barrett/systems/detail/summer-polarity-inl.h

/*
        Copyright 2009, 2010 Barrett Technology <support@barrett.com>

        This file is part of libbarrett.

        This version of libbarrett is free software: you can redistribute it
        and/or modify it under the terms of the GNU General Public License as
        published by the Free Software Foundation, either version 3 of the
        License, or (at your option) any later version.

        This version of libbarrett 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 General Public License for more details.

        You should have received a copy of the GNU General Public License along
        with this version of libbarrett.  If not, see
        <http://www.gnu.org/licenses/>.

        Further, non-binding information about licensing is available at:
        <http://wiki.barrett.com/libbarrett/wiki/LicenseNotes>
*/

/*
 * summer-polarity-inl.h
 *
 *  Created on: Sep 12, 2009
 *      Author: dc
 */

#include <string>
#include <stdexcept>


namespace barrett {
namespace systems {


template<typename T, size_t numInputs, bool RequiresAlignment>
Summer<T, numInputs, RequiresAlignment>::Polarity::Polarity() :  // default: all positive
        polarity()
{
        polarity.set();
}

template<typename T, size_t numInputs, bool RequiresAlignment>
Summer<T, numInputs, RequiresAlignment>::Polarity::Polarity(std::string polarityStr)
throw(std::invalid_argument) :
        polarity()
{
        if (polarityStr.size() != numInputs) {
                throw std::invalid_argument("(systems::Summer::Polarity::Polarity): "
                                            "polarityStr must be of the same length "
                                            "as the number of inputs to the Summer.");
        }

        for (size_t i = 0; i < numInputs; ++i) {
                switch (polarityStr[i]) {
                case '+':
                        polarity.set(i);
                        break;
                case '-':
                        polarity.reset(i);
                        break;
                default:
                        throw std::invalid_argument(
                                        "(systems::Summer::Polarity::Polarity): polarityStr must "
                                        "contain only '+' and '-' characters.");
                        break;
                }
        }
}

template<typename T, size_t numInputs, bool RequiresAlignment>
inline int Summer<T, numInputs, RequiresAlignment>::Polarity::operator[] (const size_t i) const
{
        return polarity[i] ? 1 : -1;
}


}
}