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/********************* */
/*! \file rational_gmp_imp.cpp
** \verbatim
** Top contributors (to current version):
** Tim King, Christopher L. Conway, Morgan Deters
** This file is part of the CVC4 project.
** Copyright (c) 2009-2019 by the authors listed in the file AUTHORS
** in the top-level source directory) and their institutional affiliations.
** All rights reserved. See the file COPYING in the top-level source
** directory for licensing information.\endverbatim
**
** \brief A multi-precision rational constant.
**
** A multi-precision rational constant.
**/
#include "util/rational.h"
#include <cmath>
#include <sstream>
#include <string>
#include "cvc4autoconfig.h"
#ifndef CVC4_GMP_IMP // Make sure this comes after cvc4autoconfig.h
# error "This source should only ever be built if CVC4_GMP_IMP is on !"
#endif /* CVC4_GMP_IMP */
#include "base/cvc4_assert.h"
namespace CVC4 {
std::ostream& operator<<(std::ostream& os, const Rational& q){
return os << q.toString();
}
/* Computes a rational given a decimal string. The rational
* version of <code>xxx.yyy</code> is <code>xxxyyy/(10^3)</code>.
*/
Rational Rational::fromDecimal(const std::string& dec) {
using std::string;
// Find the decimal point, if there is one
string::size_type i( dec.find(".") );
if( i != string::npos ) {
/* Erase the decimal point, so we have just the numerator. */
Integer numerator( string(dec).erase(i,1) );
/* Compute the denominator: 10 raise to the number of decimal places */
int decPlaces = dec.size() - (i + 1);
Integer denominator( Integer(10).pow(decPlaces) );
return Rational( numerator, denominator );
} else {
/* No decimal point, assume it's just an integer. */
return Rational( dec );
}
}
/** Equivalent to calling (this->abs()).cmp(b.abs()) */
int Rational::absCmp(const Rational& q) const{
const Rational& r = *this;
int rsgn = r.sgn();
int qsgn = q.sgn();
if(rsgn == 0){
return (qsgn == 0) ? 0 : -1;
}else if(qsgn == 0){
Assert(rsgn != 0);
return 1;
}else if((rsgn > 0) && (qsgn > 0)){
return r.cmp(q);
}else if((rsgn < 0) && (qsgn < 0)){
// if r < q < 0, q.cmp(r) = +1, (r.abs()).cmp(q.abs()) = +1
// if q < r < 0, q.cmp(r) = -1, (r.abs()).cmp(q.abs()) = -1
// if q = r < 0, q.cmp(r) = 0, (r.abs()).cmp(q.abs()) = 0
return q.cmp(r);
}else if((rsgn < 0) && (qsgn > 0)){
Rational rpos = -r;
return rpos.cmp(q);
}else {
Assert(rsgn > 0 && (qsgn < 0));
Rational qpos = -q;
return r.cmp(qpos);
}
}
/** Return an exact rational for a double d. */
Maybe<Rational> Rational::fromDouble(double d)
{
using namespace std;
if(isfinite(d)){
Rational q;
mpq_set_d(q.d_value.get_mpq_t(), d);
return q;
}
return Maybe<Rational>();
}
} /* namespace CVC4 */
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