variable.cc File Reference

#include "config.h"
#include <string.h>
#include "cf_assert.h"
#include "cf_defs.h"
#include "variable.h"
#include "canonicalform.h"
#include "cf_factory.h"
#include "int_poly.h"
#include "cf_iter.h"

Go to the source code of this file.

Data Structures
class	ext_entry

Functions
static CanonicalForm	conv2mipo (const CanonicalForm &mipo, const Variable &alpha)
Variable	rootOf (const CanonicalForm &mipo, char name)
	returns a symbolic root of polynomial with name name Use it to define algebraic variables More...
InternalPoly *	getInternalMipo (const Variable &alpha)
CanonicalForm	getMipo (const Variable &alpha, const Variable &x)
CanonicalForm	getMipo (const Variable &alpha)
void	setMipo (const Variable &alpha, const CanonicalForm &mipo)
bool	hasMipo (const Variable &alpha)
bool	getReduce (const Variable &alpha)
void	setReduce (const Variable &alpha, bool reduce)
char	getDefaultVarName ()
char	getDefaultExtName ()
int	ExtensionLevel ()
void	prune (Variable &alpha)
void	prune1 (const Variable &alpha)
void	Reduce (bool on)

Variables
STATIC_VAR ext_entry *	algextensions = 0
STATIC_VAR char *	var_names = 0
STATIC_VAR char *	var_names_ext = 0
STATIC_VAR char	default_name = 'v'
STATIC_VAR char	default_name_ext = 'a'

Function Documentation

conv2mipo()

static CanonicalForm conv2mipo ( const CanonicalForm &  mipo, const Variable &  alpha  )

static

Definition at line 154 of file variable.cc.

{
    CanonicalForm result;
    for ( CFIterator i = mipo; i.hasTerms(); i++ )
        result += i.coeff() * power( alpha, i.exp() );
    return result;
}

ExtensionLevel()

int ExtensionLevel

(

)

Definition at line 254 of file variable.cc.

{
  if( var_names_ext == 0)
    return 0;
  return strlen( var_names_ext )-1;
}

getDefaultExtName()

char getDefaultExtName

(

)

Definition at line 249 of file variable.cc.

{
    return default_name_ext;
}

getDefaultVarName()

char getDefaultVarName

(

)

Definition at line 244 of file variable.cc.

{
    return default_name;
}

getInternalMipo()

InternalPoly * getInternalMipo

(

const Variable &

alpha

)

Definition at line 201 of file variable.cc.

{
    ASSERT( alpha.level() < 0 && alpha.level() != LEVELBASE, "illegal extension" );
    return algextensions[-alpha.level()].mipo();
}

getMipo() [1/2]

CanonicalForm getMipo

(

const Variable &

alpha

)

Definition at line 213 of file variable.cc.

{
    ASSERT( alpha.level() < 0 && alpha.level() != LEVELBASE, "illegal extension" );
    return CanonicalForm( algextensions[-alpha.level()].mipo()->copyObject() );
}

getMipo() [2/2]

CanonicalForm getMipo	(	const Variable &	alpha,
		const Variable &	x
	)

Definition at line 207 of file variable.cc.

{
    ASSERT( alpha.level() < 0 && alpha.level() != LEVELBASE, "illegal extension" );
    return CanonicalForm( algextensions[-alpha.level()].mipo()->copyObject() )(x,alpha);
}

getReduce()

bool getReduce

(

const Variable &

alpha

)

Definition at line 232 of file variable.cc.

{
    ASSERT( alpha.level() < 0 && alpha.level() != LEVELBASE, "illegal extension" );
    return algextensions[-alpha.level()].reduce();
}

hasMipo()

bool hasMipo

(

const Variable &

alpha

)

Definition at line 226 of file variable.cc.

{
    ASSERT( alpha.level() < 0, "illegal extension" );
    return (alpha.level() != LEVELBASE && (algextensions!=NULL) && getReduce(alpha) );
}

prune()

void prune

(

Variable &

alpha

)

Definition at line 261 of file variable.cc.

{
  if (alpha.level()==LEVELBASE) return;
  int last_var=-alpha.level();
  if ((last_var <= 0)||(var_names_ext==NULL)) return;
  int i, n = strlen( var_names_ext );
  ASSERT (n+1 >= last_var, "wrong variable");
  if (last_var == 1)
  {
    delete [] var_names_ext;
    delete [] algextensions;
    var_names_ext= 0;
    algextensions= 0;
    alpha= Variable();
    return;
  }
  char * newvarnames = new char [last_var+1];
  for ( i = 0; i < last_var; i++ )
    newvarnames[i] = var_names_ext[i];
  newvarnames[last_var] = 0;
  delete [] var_names_ext;
  var_names_ext = newvarnames;
  ext_entry * newalgext = new ext_entry [last_var];
  for ( i = 0; i < last_var; i++ )
    newalgext[i] = algextensions[i];
  delete [] algextensions;
  algextensions = newalgext;
  alpha= Variable();
}

prune1()

void prune1

(

const Variable &

alpha

)

Definition at line 291 of file variable.cc.

{
  int i, n = strlen( var_names_ext );
  ASSERT (n+1 >= -alpha.level(), "wrong variable");
 
  char * newvarnames = new char [-alpha.level() + 2];
  for ( i = 0; i <= -alpha.level(); i++ )
    newvarnames[i] = var_names_ext[i];
  newvarnames[-alpha.level()+1] = 0;
  delete [] var_names_ext;
  var_names_ext = newvarnames;
  ext_entry * newalgext = new ext_entry [-alpha.level()+1];
  for ( i = 0; i <= -alpha.level(); i++ )
    newalgext[i] = algextensions[i];
  delete [] algextensions;
  algextensions = newalgext;
}

Reduce()

void Reduce

(

bool

on

)

Definition at line 309 of file variable.cc.

{
  int i;
  for (i=ExtensionLevel(); i>0;i--)
  {
    Variable l(-i);
    setReduce(l,on);
  }
}

rootOf()

Variable rootOf	(	const CanonicalForm &	mipo,
		char	name
	)

returns a symbolic root of polynomial with name name Use it to define algebraic variables

Use it to define algebraic variables

Note

: algebraic variables have a level < 0

Definition at line 162 of file variable.cc.

{
    ASSERT (mipo.isUnivariate(), "not a legal extension");
 
    int l;
    if ( var_names_ext == 0 ) {
        var_names_ext = new char [3];
        var_names_ext[0] = '@';
        var_names_ext[1] = name;
        var_names_ext[2] = '\0';
        l = 1;
        Variable result( -l, true );
        algextensions = new ext_entry [2];
        algextensions[1] = ext_entry( 0, false );
        algextensions[1] = ext_entry( (InternalPoly*)(conv2mipo( mipo, result ).getval()), true );
        return result;
    }
    else {
        int i, n = strlen( var_names_ext );
        char * newvarnames = new char [n+2];
        for ( i = 0; i < n; i++ )
            newvarnames[i] = var_names_ext[i];
        newvarnames[n] = name;
        newvarnames[n+1] = 0;
        delete [] var_names_ext;
        var_names_ext = newvarnames;
        l = n;
        Variable result( -l, true );
        ext_entry * newalgext = new ext_entry [n+1];
        for ( i = 0; i < n; i++ )
            newalgext[i] = algextensions[i];
        newalgext[n] = ext_entry( 0, false );
        delete [] algextensions;
        algextensions = newalgext;
        algextensions[n] = ext_entry( (InternalPoly*)(conv2mipo( mipo, result ).getval()), true );
        return result;
    }
}

setMipo()

void setMipo	(	const Variable &	alpha,
		const CanonicalForm &	mipo
	)

Definition at line 219 of file variable.cc.

{
    ASSERT( alpha.level() < 0 && alpha.level() != LEVELBASE, "illegal extension" );
    algextensions[-alpha.level()]= ext_entry( 0, false );
    algextensions[-alpha.level()]= ext_entry((InternalPoly*)(conv2mipo( mipo, alpha ).getval()), true );
}

setReduce()

void setReduce	(	const Variable &	alpha,
		bool	reduce
	)

Definition at line 238 of file variable.cc.

{
    ASSERT( alpha.level() < 0 && alpha.level() != LEVELBASE, "illegal extension" );
    algextensions[-alpha.level()].reduce() = reduce;
}

Variable Documentation

algextensions

STATIC_VAR ext_entry* algextensions = 0

Definition at line 41 of file variable.cc.

default_name

STATIC_VAR char default_name = 'v'

Definition at line 44 of file variable.cc.

default_name_ext

STATIC_VAR char default_name_ext = 'a'

Definition at line 45 of file variable.cc.

var_names

STATIC_VAR char* var_names = 0

Definition at line 42 of file variable.cc.

var_names_ext

STATIC_VAR char* var_names_ext = 0

Definition at line 43 of file variable.cc.