/* emacs edit mode for this file is -*- C++ -*- */

#ifndef INCL_CF_ALGORITHM_H
#define INCL_CF_ALGORITHM_H

//{{{ docu
//
// cf_algorithm.h - declarations of higher level algorithms.
//
// Header file corresponds to: cf_algorithms.cc, cf_chinese.cc,
//   cf_factor.cc, cf_linsys.cc, cf_resultant.cc
//
// Hierarchy: mathematical algorithms on canonical forms
//
// Developers note:
// ----------------
// This header file collects declarations of most of the
// functions in Factory which implement higher level algorithms
// on canonical forms (factorization, gcd, etc.) and declarations
// of some low level mathematical functions, too (absolute value,
// euclidean norm, etc.).
//
//}}}

// #include "config.h"

#include "canonicalform.h"
#include "variable.h"

/*BEGINPUBLIC*/

//{{{ function declarations from cf_algorithm.cc
CanonicalForm psr ( const CanonicalForm & f, const CanonicalForm & g, const Variable & x );

CanonicalForm psq ( const CanonicalForm & f, const CanonicalForm & g, const Variable & x );

void psqr ( const CanonicalForm & f, const CanonicalForm & g, CanonicalForm & q, CanonicalForm & r, const Variable & x );

CanonicalForm bCommonDen ( const CanonicalForm & f );

bool fdivides ( const CanonicalForm & f, const CanonicalForm & g );

bool fdivides ( const CanonicalForm & f, const CanonicalForm & g, CanonicalForm& quot );

bool tryFdivides ( const CanonicalForm & f, const CanonicalForm & g, const CanonicalForm& M, bool& fail );

CanonicalForm maxNorm ( const CanonicalForm & f );

CanonicalForm euclideanNorm ( const CanonicalForm & f );
//}}}

//{{{ function declarations from cf_chinese.cc
void chineseRemainder ( const CanonicalForm & x1, const CanonicalForm & q1, const CanonicalForm & x2, const CanonicalForm & q2, CanonicalForm & xnew, CanonicalForm & qnew );

void chineseRemainder ( const CFArray & x, const CFArray & q, CanonicalForm & xnew, CanonicalForm & qnew );

CanonicalForm Farey ( const CanonicalForm & f, const CanonicalForm & q );
//}}}

//{{{ function declarations from cf_factor.cc
extern int singular_homog_flag;

bool isPurePoly(const CanonicalForm & f);

bool isPurePoly_m(const CanonicalForm & f);

CFFList factorize ( const CanonicalForm & f, bool issqrfree = false );

CFFList factorize ( const CanonicalForm & f, const Variable & alpha );

CFFList sqrFree ( const CanonicalForm & f, bool sort= false );

bool isSqrFree ( const CanonicalForm & f );

CanonicalForm homogenize( const CanonicalForm & f, const Variable & x);
CanonicalForm homogenize( const CanonicalForm & f, const Variable & x,
                                const Variable & v1, const Variable & v2);
Variable get_max_degree_Variable(const CanonicalForm & f);
CFList get_Terms( const CanonicalForm & f );
void getTerms( const CanonicalForm & f, const CanonicalForm & t, CFList & result );


//}}}

//{{{ function declarations from cf_linsys.cc
bool linearSystemSolve ( CFMatrix & M );

CanonicalForm determinant ( const CFMatrix & M, int n );
//}}}

//{{{ function declarations from cf_resultant.cc
CFArray subResChain ( const CanonicalForm & f, const CanonicalForm & g, const Variable & x );

CanonicalForm resultant ( const CanonicalForm & f, const CanonicalForm & g, const Variable & x );
//}}}

//{{{ inline CanonicalForm abs ( const CanonicalForm & f )
//{{{ docu
//
// abs() - return absolute value of `f'.
//
// The absolute value is defined in terms of the function
// `sign()'.  If it reports negative sign for `f' than -`f' is
// returned, otherwise `f'.
//
// This behaviour is most useful for integers and rationals.  But
// it may be used to sign-normalize the leading coefficient of
// arbitrary polynomials, too.
//
// Type info:
// ----------
// f: CurrentPP
//
//}}}
inline CanonicalForm
abs ( const CanonicalForm & f )
{
    // it is not only more general to use `sign()' instead of a
    // direct comparison `f < 0', it is faster, too
    if ( sign( f ) < 0 )
        return -f;
    else
        return f;
}
//}}}

/*ENDPUBLIC*/

#endif /* ! INCL_CF_ALGORITHM_H */