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#ifndef LIB2GEOM_UTILS_HEADER
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#define LIB2GEOM_UTILS_HEADER
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/** Various utility functions.
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 *
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 * Copyright 2007 Johan Engelen <goejendaagh@zonnet.nl>
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 * Copyright 2006 Michael G. Sloan <mgsloan@gmail.com>
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 *
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 * This library is free software; you can redistribute it and/or
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 * modify it either under the terms of the GNU Lesser General Public
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 * License version 2.1 as published by the Free Software Foundation
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 * (the "LGPL") or, at your option, under the terms of the Mozilla
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 * Public License Version 1.1 (the "MPL"). If you do not alter this
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 * notice, a recipient may use your version of this file under either
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 * the MPL or the LGPL.
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 *
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 * You should have received a copy of the LGPL along with this library
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 * in the file COPYING-LGPL-2.1; if not, write to the Free Software
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 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
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 * You should have received a copy of the MPL along with this library
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 * in the file COPYING-MPL-1.1
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 *
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 * The contents of this file are subject to the Mozilla Public License
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 * Version 1.1 (the "License"); you may not use this file except in
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 * compliance with the License. You may obtain a copy of the License at
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 * http://www.mozilla.org/MPL/
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 *
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 * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY
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 * OF ANY KIND, either express or implied. See the LGPL or the MPL for
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 * the specific language governing rights and limitations.
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 *
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 */
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#include <cmath>
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namespace Geom {
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// proper logical xor
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inline bool logical_xor (bool a, bool b) { return (a || b) && !(a && b); }
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/** Sign function - indicates the sign of a numeric type.  -1 indicates negative, 1 indicates
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 *  positive, and 0 indicates, well, 0.  Mathsy people will know this is basically the derivative
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 *  of abs, except for the fact that it is defined on 0.
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 */
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template <class T> inline int sgn(const T& x) {return (x < 0 ? -1 : (x > 0 ? 1 : 0) );}
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template <class T> inline T sqr(const T& x) {return x * x;}
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template <class T> inline T cube(const T& x) {return x * x * x;}
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/** Between function - returns true if a number x is within a range. The values delimiting the
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 *  range and the number must have the same type.
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 */
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template <class T> inline const T& between (const T& min, const T& max, const T& x)
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    { return min < x && max > x; }
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/** Returns x rounded to the nearest integer.  It is unspecified what happens
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 *  if x is half way between two integers: we may in future use rint/round
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 *  on platforms that have them.
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 */
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inline double round(double const x) { return std::floor(x + .5); }
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/** Returns x rounded to the nearest \a places decimal places.
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    Implemented in terms of round, i.e. we make no guarantees as to what happens if x is
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    half way between two rounded numbers.
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    Note: places is the number of decimal places without using scientific (e) notation, not the
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    number of significant figures.  This function may not be suitable for values of x whose
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    magnitude is so far from 1 that one would want to use scientific (e) notation.
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    places may be negative: e.g. places = -2 means rounding to a multiple of .01
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**/
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inline double decimal_round(double const x, int const places) {
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    //TODO: possibly implement with modulus instead?
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    double const multiplier = std::pow(10.0, places);
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    return round( x * multiplier ) / multiplier;
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}
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}
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#endif