windows-nt/Source/XPSP1/NT/shell/osshell/accesory/ratpak/conv.c
2020-09-26 16:20:57 +08:00

1548 lines
39 KiB
C

//---------------------------------------------------------------------------
// Package Title ratpak
// File conv.c
// Author Timothy David Corrie Jr. (timc@microsoft.com)
// Copyright (C) 1995-97 Microsoft
// Date 01-16-95
//
//
// Description
//
// Contains conversion, input and output routines for numbers rationals
// and longs.
//
//
//
//---------------------------------------------------------------------------
#include <stdio.h>
#include <tchar.h> // TCHAR version of sprintf
#include <string.h>
#include <malloc.h>
#include <stdlib.h>
#if defined( DOS )
#include <dosstub.h>
#else
#include <windows.h>
#endif
#include <ratpak.h>
BOOL fparserror=FALSE;
BOOL gbinexact=FALSE;
// digits 0..64 used by bases 2 .. 64
TCHAR digits[65]=TEXT("0123456789")
TEXT("ABCDEFGHIJKLMNOPQRSTUVWXYZ")
TEXT("abcdefghijklmnopqrstuvwxyz_@");
// ratio of internal 'digits' to output 'digits'
// Calculated elsewhere as part of initialization and when base is changed
long ratio; // int(log(2L^BASEXPWR)/log(nRadix))
// Used to strip trailing zeroes, and prevent combinatorial explosions
BOOL stripzeroesnum( PNUMBER pnum, long starting );
// returns int(lognRadix(x)) quickly.
long longlognRadix( long x );
//----------------------------------------------------------------------------
//
// FUNCTION: fail
//
// ARGUMENTS: pointer to an error message.
//
// RETURN: None
//
// DESCRIPTION: fail dumps the error message then throws an exception
//
//----------------------------------------------------------------------------
void fail( IN long errmsg )
{
#ifdef DEBUG
fprintf( stderr, "%s\n", TEXT("Out of Memory") );
#endif
throw( CALC_E_OUTOFMEMORY );
}
//-----------------------------------------------------------------------------
//
// FUNCTION: _destroynum
//
// ARGUMENTS: pointer to a number
//
// RETURN: None
//
// DESCRIPTION: Deletes the number and associated allocation
//
//-----------------------------------------------------------------------------
void _destroynum( IN PNUMBER pnum )
{
if ( pnum != NULL )
{
zfree( pnum );
}
}
//-----------------------------------------------------------------------------
//
// FUNCTION: _destroyrat
//
// ARGUMENTS: pointer to a rational
//
// RETURN: None
//
// DESCRIPTION: Deletes the rational and associated
// allocations.
//
//-----------------------------------------------------------------------------
void _destroyrat( IN PRAT prat )
{
if ( prat != NULL )
{
destroynum( prat->pp );
destroynum( prat->pq );
zfree( prat );
}
}
//-----------------------------------------------------------------------------
//
// FUNCTION: _createnum
//
// ARGUMENTS: size of number in 'digits'
//
// RETURN: pointer to a number
//
// DESCRIPTION: allocates and zeroes out number type.
//
//-----------------------------------------------------------------------------
PNUMBER _createnum( IN long size )
{
PNUMBER pnumret=NULL;
// sizeof( MANTTYPE ) is the size of a 'digit'
pnumret = (PNUMBER)zmalloc( (int)(size+1) * sizeof( MANTTYPE ) +
sizeof( NUMBER ) );
if ( pnumret == NULL )
{
fail( CALC_E_OUTOFMEMORY );
}
return( pnumret );
}
//-----------------------------------------------------------------------------
//
// FUNCTION: _createrat
//
// ARGUMENTS: none
//
// RETURN: pointer to a rational
//
// DESCRIPTION: allocates a rational structure but does not
// allocate the numbers that make up the rational p over q
// form. These number pointers are left pointing to null.
//
//-----------------------------------------------------------------------------
PRAT _createrat( void )
{
PRAT prat=NULL;
prat = (PRAT)zmalloc( sizeof( RAT ) );
if ( prat == NULL )
{
fail( CALC_E_OUTOFMEMORY );
}
prat->pp = NULL;
prat->pq = NULL;
return( prat );
}
//-----------------------------------------------------------------------------
//
// FUNCTION: numtorat
//
// ARGUMENTS: pointer to a number, nRadix number is in.
//
// RETURN: Rational representation of number.
//
// DESCRIPTION: The rational representation of the number
// is guaranteed to be in the form p (number with internal
// base representation) over q (number with internal base
// representation) Where p and q are integers.
//
//-----------------------------------------------------------------------------
PRAT numtorat( IN PNUMBER pin, IN unsigned long nRadix )
{
PRAT pout=NULL;
PNUMBER pnRadixn=NULL;
PNUMBER qnRadixn=NULL;
DUPNUM( pnRadixn, pin );
qnRadixn=longtonum( 1, nRadix );
// Ensure p and q start out as integers.
if ( pnRadixn->exp < 0 )
{
qnRadixn->exp -= pnRadixn->exp;
pnRadixn->exp = 0;
}
createrat(pout);
// There is probably a better way to do this.
pout->pp = numtonRadixx( pnRadixn, nRadix, ratio );
pout->pq = numtonRadixx( qnRadixn, nRadix, ratio );
destroynum( pnRadixn );
destroynum( qnRadixn );
return( pout );
}
//----------------------------------------------------------------------------
//
// FUNCTION: nRadixxtonum
//
// ARGUMENTS: pointer to a number, base requested.
//
// RETURN: number representation in nRadix requested.
//
// DESCRIPTION: Does a base conversion on a number from
// internal to requested base. Assumes number being passed
// in is really in internal base form.
//
//----------------------------------------------------------------------------
PNUMBER nRadixxtonum( IN PNUMBER a, IN unsigned long nRadix )
{
PNUMBER sum=NULL;
PNUMBER powofnRadix=NULL;
unsigned long bitmask;
unsigned long cdigits;
MANTTYPE *ptr;
sum = longtonum( 0, nRadix );
powofnRadix = longtonum( BASEX, nRadix );
// A large penalty is paid for conversion of digits no one will see anyway.
// limit the digits to the minimum of the existing precision or the
// requested precision.
cdigits = maxout + 1;
if ( cdigits > (unsigned long)a->cdigit )
{
cdigits = (unsigned long)a->cdigit;
}
// scale by the internal base to the internal exponent offset of the LSD
numpowlong( &powofnRadix, a->exp + (a->cdigit - cdigits), nRadix );
// Loop over all the relative digits from MSD to LSD
for ( ptr = &(MANT(a)[a->cdigit-1]); cdigits > 0 && !fhalt;
ptr--, cdigits-- )
{
// Loop over all the bits from MSB to LSB
for ( bitmask = BASEX/2; bitmask > 0; bitmask /= 2 )
{
addnum( &sum, sum, nRadix );
if ( *ptr & bitmask )
{
sum->mant[0] |= 1;
}
}
}
// Scale answer by power of internal exponent.
mulnum( &sum, powofnRadix, nRadix );
destroynum( powofnRadix );
sum->sign = a->sign;
return( sum );
}
//-----------------------------------------------------------------------------
//
// FUNCTION: numtonRadixx
//
// ARGUMENTS: pointer to a number, nRadix of that number.
// previously calculated ratio
//
// RETURN: number representation in internal nRadix.
//
// DESCRIPTION: Does a nRadix conversion on a number from
// specified nRadix to requested nRadix. Assumes the nRadix
// specified is the nRadix of the number passed in.
//
//-----------------------------------------------------------------------------
PNUMBER numtonRadixx( IN PNUMBER a, IN unsigned long nRadix, IN long ratio )
{
PNUMBER pnumret = NULL; // pnumret is the number in internal form.
PNUMBER thisdigit = NULL; // thisdigit holds the current digit of a
// being summed into result.
PNUMBER powofnRadix = NULL; // offset of external base exponent.
MANTTYPE *ptrdigit; // pointer to digit being worked on.
long idigit; // idigit is the iterate of digits in a.
pnumret = longtonum( 0, BASEX );
ptrdigit = MANT(a);
// Digits are in reverse order, back over them LSD first.
ptrdigit += a->cdigit-1;
for ( idigit = 0; idigit < a->cdigit; idigit++ )
{
mulnumx( &pnumret, num_nRadix );
// WARNING:
// This should just smack in each digit into a 'special' thisdigit.
// and not do the overhead of recreating the number type each time.
thisdigit = longtonum( *ptrdigit--, BASEX );
addnum( &pnumret, thisdigit, BASEX );
destroynum( thisdigit );
}
DUPNUM( powofnRadix, num_nRadix );
// Calculate the exponent of the external base for scaling.
numpowlongx( &powofnRadix, a->exp );
// ... and scale the result.
mulnumx( &pnumret, powofnRadix );
destroynum( powofnRadix );
// And propagate the sign.
pnumret->sign = a->sign;
return( pnumret );
}
//-----------------------------------------------------------------------------
//
// FUNCTION: inrat
//
// ARGUMENTS:
// fMantIsNeg true if mantissa is less than zero
// pszMant a string representation of a number
// fExpIsNeg true if exponent is less than zero
// pszExp a string representation of a number
//
// RETURN: prat representation of string input.
// Or NULL if no number scanned.
//
// EXPLANATION: This is for calc.
//
//
//-----------------------------------------------------------------------------
PRAT inrat( IN BOOL fMantIsNeg, IN LPTSTR pszMant, IN BOOL fExpIsNeg,
IN LPTSTR pszExp )
{
PNUMBER pnummant=NULL; // holds mantissa in number form.
PNUMBER pnumexp=NULL; // holds exponent in number form.
PRAT pratexp=NULL; // holds exponent in rational form.
PRAT prat=NULL; // holds exponent in rational form.
long expt; // holds exponent
// Deal with Mantissa
if ( ( pszMant == NULL ) || ( *pszMant == TEXT('\0') ) )
{
// Preset value if no mantissa
if ( ( pszExp == NULL ) || ( *pszExp == TEXT('\0') ) )
{
// Exponent not specified, preset value to zero
DUPRAT(prat,rat_zero);
}
else
{
// Exponent specified, preset value to one
DUPRAT(prat,rat_one);
}
}
else
{
// Mantissa specified, convert to number form.
pnummant = innum( pszMant );
if ( pnummant == NULL )
{
return( NULL );
}
prat = numtorat( pnummant, nRadix );
// convert to rational form, and cleanup.
destroynum(pnummant);
}
if ( ( pszExp == NULL ) || ( *pszExp == TEXT('\0') ) )
{
// Exponent not specified, preset value to zero
expt=0;
}
else
{
// Exponent specified, convert to number form.
// Don't use native stuff, as it is restricted in the bases it can
// handle.
pnumexp = innum( pszExp );
if ( pnumexp == NULL )
{
return( NULL );
}
// Convert exponent number form to native integral form, and cleanup.
expt = numtolong( pnumexp, nRadix );
destroynum( pnumexp );
}
// Convert native integral exponent form to rational multiplier form.
pnumexp=longtonum( nRadix, BASEX );
numpowlongx(&(pnumexp),abs(expt));
createrat(pratexp);
DUPNUM( pratexp->pp, pnumexp );
pratexp->pq = longtonum( 1, BASEX );
destroynum(pnumexp);
if ( fExpIsNeg )
{
// multiplier is less than 1, this means divide.
divrat( &prat, pratexp );
}
else
{
if ( expt > 0 )
{
// multiplier is greater than 1, this means divide.
mulrat(&prat, pratexp);
}
// multiplier can be 1, in which case it'd be a waste of time to
// multiply.
}
if ( fMantIsNeg )
{
// A negative number was used, adjust the sign.
prat->pp->sign *= -1;
}
return( prat );
}
//-----------------------------------------------------------------------------
//
// FUNCTION: innum
//
// ARGUMENTS:
// TCHAR *buffer
//
// RETURN: pnumber representation of string input.
// Or NULL if no number scanned.
//
// EXPLANATION: This is a state machine,
//
// State Description Example, ^shows just read position.
// which caused the transition
//
// START Start state ^1.0
// MANTS Mantissa sign -^1.0
// LZ Leading Zero 0^1.0
// LZDP Post LZ dec. pt. 000.^1
// LD Leading digit 1^.0
// DZ Post LZDP Zero 000.0^1
// DD Post Decimal digit .01^2
// DDP Leading Digit dec. pt. 1.^2
// EXPB Exponent Begins 1.0e^2
// EXPS Exponent sign 1.0e+^5
// EXPD Exponent digit 1.0e1^2 or even 1.0e0^1
// EXPBZ Exponent begin post 0 0.000e^+1
// EXPSZ Exponent sign post 0 0.000e+^1
// EXPDZ Exponent digit post 0 0.000e+1^2
// ERR Error case 0.0.^
//
// Terminal Description
//
// DP '.'
// ZR '0'
// NZ '1'..'9' 'A'..'Z' 'a'..'z' '@' '_'
// SG '+' '-'
// EX 'e' '^' e is used for nRadix 10, ^ for all other nRadixs.
//
//-----------------------------------------------------------------------------
#define DP 0
#define ZR 1
#define NZ 2
#define SG 3
#define EX 4
#define START 0
#define MANTS 1
#define LZ 2
#define LZDP 3
#define LD 4
#define DZ 5
#define DD 6
#define DDP 7
#define EXPB 8
#define EXPS 9
#define EXPD 10
#define EXPBZ 11
#define EXPSZ 12
#define EXPDZ 13
#define ERR 14
#if defined( DEBUG )
char *statestr[] = {
"START",
"MANTS",
"LZ",
"LZDP",
"LD",
"DZ",
"DD",
"DDP",
"EXPB",
"EXPS",
"EXPD",
"EXPBZ",
"EXPSZ",
"EXPDZ",
"ERR",
};
#endif
// New state is machine[state][terminal]
char machine[ERR+1][EX+1]= {
// DP, ZR, NZ, SG, EX
// START
{ LZDP, LZ, LD, MANTS, ERR },
// MANTS
{ LZDP, LZ, LD, ERR, ERR },
// LZ
{ LZDP, LZ, LD, ERR, EXPBZ },
// LZDP
{ ERR, DZ, DD, ERR, EXPB },
// LD
{ DDP, LD, LD, ERR, EXPB },
// DZ
{ ERR, DZ, DD, ERR, EXPBZ },
// DD
{ ERR, DD, DD, ERR, EXPB },
// DDP
{ ERR, DD, DD, ERR, EXPB },
// EXPB
{ ERR, EXPD, EXPD, EXPS, ERR },
// EXPS
{ ERR, EXPD, EXPD, ERR, ERR },
// EXPD
{ ERR, EXPD, EXPD, ERR, ERR },
// EXPBZ
{ ERR, EXPDZ, EXPDZ, EXPSZ, ERR },
// EXPSZ
{ ERR, EXPDZ, EXPDZ, ERR, ERR },
// EXPDZ
{ ERR, EXPDZ, EXPDZ, ERR, ERR },
// ERR
{ ERR, ERR, ERR, ERR, ERR }
};
PNUMBER innum( IN TCHAR *buffer )
{
int c; // c is character being worked on currently.
int state; // state is the state of the input state machine.
long exps = 1L; // exps is exponent sign ( +/- 1 )
long expt = 0L; // expt is exponent mantissa, should be unsigned
long length = 0L; // length is the length of the input string.
MANTTYPE *pmant; //
PNUMBER pnumret=NULL; //
length = _tcslen(buffer);
createnum( pnumret, length );
pnumret->sign = 1L;
pnumret->cdigit = 0;
pnumret->exp = 0;
pmant = MANT(pnumret)+length-1;
state = START;
fparserror=FALSE; // clear global flag for parse error initially.
while ( ( c = *buffer ) && c != TEXT('\n') )
{
int dp;
dp = 0;
// Added code to deal with international decimal point.
while ( szDec[dp] && ( szDec[dp] == *buffer ) )
{
dp++;
buffer++;
}
if ( dp )
{
if ( szDec[dp] == TEXT('\0') )
{
// OK pretend that was a decimal point for the state machine
c = TEXT('.');
buffer--;
}
else
{
// Backup that was no decimal point
buffer -= (dp-1);
c = *buffer++;
}
}
switch ( c )
{
case TEXT('-'):
case TEXT('+'):
state=machine[state][SG];
break;
case TEXT('.'):
state=machine[state][DP];
break;
case TEXT('0'):
state=machine[state][ZR];
break;
case TEXT('^'):
case TEXT('e'):
if ( ( c == TEXT('^') ) || ( nRadix == 10 ) )
{
state=machine[state][EX];
break;
}
// WARNING tricky dropthrough in the TEXT('e') as a digit case!!!
default:
state=machine[state][NZ];
break;
}
switch ( state )
{
case MANTS:
pnumret->sign = ( ( c == TEXT('-') ) ? -1 : 1);
break;
case EXPSZ:
case EXPS:
exps = ( ( c == TEXT('-') ) ? -1 : 1);
break;
case EXPDZ:
case EXPD:
{
TCHAR *ptr; // offset into digit table.
if ( ( nRadix <= 36 ) && ( nRadix > 10 ) )
{
c = toupper( c );
}
ptr = _tcschr( digits, (TCHAR)c );
if ( ptr != NULL )
{
expt *= nRadix;
expt += (long)(ptr - digits);
}
else
{
state=ERR;
}
}
break;
case LD:
pnumret->exp++;
case DD:
{
TCHAR *ptr; // offset into digit table.
if ( ( nRadix <= 36 ) && ( nRadix > 10 ) )
{
// Allow upper and lower case letters as equivalent, base
// is in the range where this is not ambiguous.
c = toupper( c );
}
ptr = _tcschr( digits, (TCHAR)c );
if ( ptr != NULL && ( (ptr - digits) < nRadix ) )
{
*pmant-- = (MANTTYPE)(ptr - digits);
pnumret->exp--;
pnumret->cdigit++;
}
else
{
state=ERR;
// set global flag for parse error just in case anyone cares.
fparserror=TRUE;
}
}
break;
case DZ:
pnumret->exp--;
break;
case LZ:
case LZDP:
case DDP:
break;
}
buffer++;
}
if ( state == DZ || state == EXPDZ )
{
pnumret->cdigit = 1;
pnumret->exp=0;
pnumret->sign=1;
}
else
{
while ( pnumret->cdigit < length )
{
pnumret->cdigit++;
pnumret->exp--;
}
pnumret->exp += exps*expt;
}
if ( pnumret->cdigit == 0 )
{
destroynum( pnumret );
pnumret = NULL;
}
stripzeroesnum( pnumret, maxout );
return( pnumret );
}
//-----------------------------------------------------------------------------
//
// FUNCTION: longtorat
//
// ARGUMENTS: long
//
// RETURN: Rational representation of long input.
//
// DESCRIPTION: Converts long input to rational (p over q)
// form, where q is 1 and p is the long.
//
//-----------------------------------------------------------------------------
PRAT longtorat( IN long inlong )
{
PRAT pratret=NULL;
createrat( pratret );
pratret->pp = longtonum(inlong, BASEX );
pratret->pq = longtonum(1L, BASEX );
return( pratret );
}
//-----------------------------------------------------------------------------
//
// FUNCTION: realtorat
//
// ARGUMENTS: double real value.
//
// RETURN: Rational representation of the double
//
// DESCRIPTION: returns the rational (p over q)
// representation of the double.
//
//-----------------------------------------------------------------------------
PRAT realtorat( IN double real )
{
#if !defined( CLEVER )
// get clever later, right now hack something to work
TCHAR *ptr;
PNUMBER pnum=NULL;
PRAT prat=NULL;
if ( ( ptr = (TCHAR*)zmalloc( 60 * sizeof(TCHAR) ) ) != NULL )
{
_stprintf( ptr, TEXT("%20.20le"), real );
pnum=innum( ptr );
prat = numtorat( pnum, nRadix );
destroynum( pnum );
zfree( ptr );
return( prat );
}
else
{
return( NULL );
}
#else
int i;
union {
double real;
BYTE split[8];
} unpack;
long expt;
long ratio;
MANTTYPE *pmant;
PNUMBER pnumret = NULL;
PRAT pratret = NULL;
createrat( pratret );
if ( real == 0.0 )
{
pnumret=longtonum( 0L, 2L );
}
else
{
unpack.real=real;
expt=unpack.split[7]*0x100+(unpack.split[6]>>4)-1023;
createnum( pnumret, 52 );
pmant = MANT(pnumret);
for ( i = 63; i > 10; i-- )
{
*pmant++ = (MANTTYPE)((unpack.split[i/8]&(1<<(i%8)))!=0);
}
pnumret->exp=expt-52;
pnumret->cdigit=52;
}
ratio = 1;
while ( ratio > BASEX )
{
ratio *= 2;
}
pratret->pp = numtonRadixx( pnumret, 2, ratio );
destroynum( pnumret );
pratret->pq=longtonum( 1L, BASEX );
if ( pratret->pp->exp < 0 )
{
pratret->pq->exp -= pratret->pp->exp;
pratret->pp->exp = 0;
}
return( pratret );
#endif
}
//-----------------------------------------------------------------------------
//
// FUNCTION: longtonum
//
// ARGUMENTS: long input and nRadix requested.
//
// RETURN: number
//
// DESCRIPTION: Returns a number representation in the
// base requested of the long value passed in.
//
//-----------------------------------------------------------------------------
PNUMBER longtonum( IN long inlong, IN unsigned long nRadix )
{
MANTTYPE *pmant;
PNUMBER pnumret=NULL;
createnum( pnumret, MAX_LONG_SIZE );
pmant = MANT(pnumret);
pnumret->cdigit = 0;
pnumret->exp = 0;
if ( inlong < 0 )
{
pnumret->sign = -1;
inlong *= -1;
}
else
{
pnumret->sign = 1;
}
do {
*pmant++ = (MANTTYPE)(inlong % nRadix);
inlong /= nRadix;
pnumret->cdigit++;
} while ( inlong );
return( pnumret );
}
//-----------------------------------------------------------------------------
//
// FUNCTION: rattolong
//
// ARGUMENTS: rational number in internal base.
//
// RETURN: long
//
// DESCRIPTION: returns the long representation of the
// number input. Assumes that the number is in the internal
// base.
//
//-----------------------------------------------------------------------------
long rattolong( IN PRAT prat )
{
long lret;
PRAT pint = NULL;
if ( rat_gt( prat, rat_dword ) || rat_lt( prat, rat_min_long ) )
{
// Don't attempt rattolong of anything too big or small
throw( CALC_E_DOMAIN );
}
DUPRAT(pint,prat);
intrat( &pint );
divnumx( &(pint->pp), pint->pq );
DUPNUM( pint->pq, num_one );
lret = numtolong( pint->pp, BASEX );
destroyrat(pint);
return( lret );
}
//-----------------------------------------------------------------------------
//
// FUNCTION: numtolong
//
// ARGUMENTS: number input and base of that number.
//
// RETURN: long
//
// DESCRIPTION: returns the long representation of the
// number input. Assumes that the number is really in the
// base claimed.
//
//-----------------------------------------------------------------------------
long numtolong( IN PNUMBER pnum, IN unsigned long nRadix )
{
long lret;
long expt;
long length;
MANTTYPE *pmant;
lret = 0;
pmant = MANT( pnum );
pmant += pnum->cdigit - 1;
expt = pnum->exp;
length = pnum->cdigit;
while ( length > 0 && length + expt > 0 )
{
lret *= nRadix;
lret += *(pmant--);
length--;
}
while ( expt-- > 0 )
{
lret *= (long)nRadix;
}
lret *= pnum->sign;
return( lret );
}
//-----------------------------------------------------------------------------
//
// FUNCTION: BOOL stripzeroesnum
//
// ARGUMENTS: a number representation
//
// RETURN: TRUE if stripping done, modifies number in place.
//
// DESCRIPTION: Strips off trailing zeroes.
//
//-----------------------------------------------------------------------------
BOOL stripzeroesnum( IN OUT PNUMBER pnum, long starting )
{
MANTTYPE *pmant;
long cdigits;
BOOL fstrip = FALSE;
// point pmant to the LeastCalculatedDigit
pmant=MANT(pnum);
cdigits=pnum->cdigit;
// point pmant to the LSD
if ( cdigits > starting )
{
pmant += cdigits - starting;
cdigits = starting;
}
// Check we haven't gone too far, and we are still looking at zeroes.
while ( ( cdigits > 0 ) && !(*pmant) )
{
// move to next significant digit and keep track of digits we can
// ignore later.
pmant++;
cdigits--;
fstrip = TRUE;
}
// If there are zeroes to remove.
if ( fstrip )
{
// Remove them.
memcpy( MANT(pnum), pmant, (int)(cdigits*sizeof(MANTTYPE)) );
// And adjust exponent and digit count accordingly.
pnum->exp += ( pnum->cdigit - cdigits );
pnum->cdigit = cdigits;
}
return( fstrip );
}
//-----------------------------------------------------------------------------
//
// FUNCTION: putnum
//
// ARGUMENTS: number representation
// fmt, one of FMT_FLOAT FMT_SCIENTIFIC or
// FMT_ENGINEERING
//
// RETURN: String representation of number.
//
// DESCRIPTION: Converts a number to it's string
// representation. Returns a string that should be
// zfree'd after use.
//
//-----------------------------------------------------------------------------
TCHAR *putnum( IN PNUMBER *ppnum, IN int fmt )
{
TCHAR *psz;
TCHAR *pret;
long expt; // Actual number of digits to the left of decimal
long eout; // Displayed exponent.
long cexp; // the size of the exponent needed.
long elen;
long length;
MANTTYPE *pmant;
int fsciform=0; // If true scientific form is called for.
PNUMBER pnum;
PNUMBER round=NULL;
long oldfmt = fmt;
pnum=*ppnum;
stripzeroesnum( pnum, maxout+2 );
length = pnum->cdigit;
expt = pnum->exp+length;
if ( ( expt > maxout ) && ( fmt == FMT_FLOAT ) )
{
// Force scientific mode to prevent user from assuming 33rd digit is
// exact.
fmt = FMT_SCIENTIFIC;
}
// Make length small enough to fit in pret.
if ( length > maxout )
{
length = maxout;
}
eout=expt-1;
cexp = longlognRadix( expt );
// 2 for signs, 1 for 'e'(or leading zero), 1 for dp, 1 for null and
// 10 for maximum exponent size.
pret = (TCHAR*)zmalloc( (maxout + 16) * sizeof(TCHAR) );
psz = pret;
if (!psz)
{
fail( CALC_E_OUTOFMEMORY );
}
// If there is a chance a round has to occour, round.
if (
// if number is zero no rounding.
!zernum( pnum ) &&
// if number of digits is less than the maximum output no rounding.
pnum->cdigit >= maxout
)
{
// Otherwise round.
round=longtonum( nRadix, nRadix );
divnum(&round, num_two, nRadix );
// Make round number exponent one below the LSD for the number.
round->exp = pnum->exp + pnum->cdigit - round->cdigit - maxout;
round->sign = pnum->sign;
}
if ( fmt == FMT_FLOAT )
{
// cexp will now contain the size required by exponential.
// Figure out if the exponent will fill more space than the nonexponent field.
if ( ( length - expt > maxout + 2 ) || ( expt > maxout + 3 ) )
{
// Case where too many zeroes are to the right or left of the
// decimal pt. And we are forced to switch to scientific form.
fmt = FMT_SCIENTIFIC;
}
else
{
// Minimum loss of precision occours with listing leading zeros
// if we need to make room for zeroes sacrifice some digits.
if ( length + abs(expt) < maxout )
{
if ( round )
{
round->exp -= expt;
}
}
}
}
if ( round != NULL )
{
BOOL fstrip=FALSE;
long offset;
addnum( ppnum, round, nRadix );
pnum=*ppnum;
offset=(pnum->cdigit+pnum->exp) - (round->cdigit+round->exp);
fstrip = stripzeroesnum( pnum, offset );
destroynum( round );
if ( fstrip )
{
// WARNING: nesting/recursion, too much has been changed, need to
// refigure format.
return( putnum( &pnum, oldfmt ) );
}
}
else
{
stripzeroesnum( pnum, maxout );
}
// Set up all the post rounding stuff.
pmant = MANT(pnum)+pnum->cdigit-1;
if (
// Case where too many digits are to the left of the decimal or
// FMT_SCIENTIFIC or FMT_ENGINEERING was specified.
( fmt == FMT_SCIENTIFIC ) ||
( fmt == FMT_ENGINEERING ) )
{
fsciform=1;
if ( eout != 0 )
{
if ( fmt == FMT_ENGINEERING )
{
expt = (eout % 3);
eout -= expt;
expt++;
// Fix the case where 0.02e-3 should really be 2.e-6 etc.
if ( expt < 0 )
{
expt += 3;
eout -= 3;
}
}
else
{
expt = 1;
}
}
}
else
{
fsciform=0;
eout=0;
}
// Make sure negative zeroes aren't allowed.
if ( ( pnum->sign == -1 ) && ( length > 0 ) )
{
*psz++ = TEXT('-');
}
if ( ( expt <= 0 ) && ( fsciform == 0 ) )
{
*psz++ = TEXT('0');
*psz++ = szDec[0];
// Used up a digit unaccounted for.
}
while ( expt < 0 )
{
*psz++ = TEXT('0');
expt++;
}
while ( length > 0 )
{
expt--;
*psz++ = digits[ *pmant-- ];
length--;
// Be more regular in using a decimal point.
if ( expt == 0 )
{
*psz++ = szDec[0];
}
}
while ( expt > 0 )
{
*psz++ = TEXT('0');
expt--;
// Be more regular in using a decimal point.
if ( expt == 0 )
{
*psz++ = szDec[0];
}
}
if ( fsciform )
{
if ( nRadix == 10 )
{
*psz++ = TEXT('e');
}
else
{
*psz++ = TEXT('^');
}
*psz++ = ( eout < 0 ? TEXT('-') : TEXT('+') );
eout = abs( eout );
elen=0;
do
{
// should this be eout % nRadix? or is that insane?
*psz++ = digits[ eout % nRadix ];
elen++;
eout /= nRadix;
} while ( eout > 0 );
*psz = TEXT('\0');
_tcsrev( &(psz[-elen]) );
}
*psz = TEXT('\0');
return( pret );
}
//-----------------------------------------------------------------------------
//
// FUNCTION: putrat
//
// ARGUMENTS:
// PRAT *representation of a number.
// long representation of base to dump to screen.
// fmt, one of FMT_FLOAT FMT_SCIENTIFIC or FMT_ENGINEERING
//
// RETURN: string
//
// DESCRIPTION: returns a string representation of rational number passed
// in, at least to the maxout digits. String returned should be zfree'd
// after use.
//
// NOTE: It may be that doing a GCD() could shorten the rational form
// And it may eventually be worthwhile to keep the result. That is
// why a pointer to the rational is passed in.
//
//-----------------------------------------------------------------------------
TCHAR *putrat( IN OUT PRAT *pa, IN unsigned long nRadix, IN int fmt )
{
TCHAR *psz;
PNUMBER p=NULL;
PNUMBER q=NULL;
long scaleby=0;
// Convert p and q of rational form from internal base to requested base.
// Scale by largest power of BASEX possible.
scaleby=min((*pa)->pp->exp,(*pa)->pq->exp);
if ( scaleby < 0 )
{
scaleby = 0;
}
(*pa)->pp->exp -= scaleby;
(*pa)->pq->exp -= scaleby;
p = nRadixxtonum( (*pa)->pp, nRadix );
q = nRadixxtonum( (*pa)->pq, nRadix );
// finally take the time hit to actually divide.
divnum( &p, q, nRadix );
psz = putnum( &p, fmt );
destroynum( p );
destroynum( q );
return( psz );
}
//-----------------------------------------------------------------------------
//
// FUNCTION: gcd
//
// ARGUMENTS:
// PNUMBER representation of a number.
// PNUMBER representation of a number.
//
// RETURN: Greatest common divisor in internal BASEX PNUMBER form.
//
// DESCRIPTION: gcd uses remainders to find the greatest common divisor.
//
// ASSUMPTIONS: gcd assumes inputs are integers.
//
// NOTE: Before GregSte and TimC proved the TRIM macro actually kept the
// size down cheaper than GCD, this routine was used extensively.
// now it is not used but might be later.
//
//-----------------------------------------------------------------------------
PNUMBER gcd( IN PNUMBER a, IN PNUMBER b )
{
PNUMBER r=NULL;
PNUMBER tmpa=NULL;
PNUMBER tmpb=NULL;
if ( lessnum( a, b ) )
{
DUPNUM(tmpa,b);
if ( zernum(a) )
{
return(tmpa);
}
DUPNUM(tmpb,a);
}
else
{
DUPNUM(tmpa,a);
if ( zernum(b) )
{
return(tmpa);
}
DUPNUM(tmpb,b);
}
remnum( &tmpa, tmpb, nRadix );
while ( !zernum( tmpa ) )
{
// swap tmpa and tmpb
r = tmpa;
tmpa = tmpb;
tmpb = r;
remnum( &tmpa, tmpb, nRadix );
}
destroynum( tmpa );
return( tmpb );
}
//-----------------------------------------------------------------------------
//
// FUNCTION: longfactnum
//
// ARGUMENTS:
// long integer to factorialize.
// long integer representing base of answer.
//
// RETURN: Factorial of input in nRadix PNUMBER form.
//
// NOTE: Not currently used.
//
//-----------------------------------------------------------------------------
PNUMBER longfactnum( IN long inlong, IN unsigned long nRadix )
{
PNUMBER lret=NULL;
PNUMBER tmp=NULL;
PNUMBER tmp1=NULL;
lret = longtonum( 1, nRadix );
while ( inlong > 0 )
{
tmp = longtonum( inlong--, nRadix );
mulnum( &lret, tmp, nRadix );
destroynum( tmp );
}
return( lret );
}
//-----------------------------------------------------------------------------
//
// FUNCTION: longprodnum
//
// ARGUMENTS:
// long integer to factorialize.
// long integer representing base of answer.
//
// RETURN: Factorial of input in base PNUMBER form.
//
//-----------------------------------------------------------------------------
PNUMBER longprodnum( IN long start, IN long stop, IN unsigned long nRadix )
{
PNUMBER lret=NULL;
PNUMBER tmp=NULL;
lret = longtonum( 1, nRadix );
while ( start <= stop )
{
if ( start )
{
tmp = longtonum( start, nRadix );
mulnum( &lret, tmp, nRadix );
destroynum( tmp );
}
start++;
}
return( lret );
}
//-----------------------------------------------------------------------------
//
// FUNCTION: numpowlong
//
// ARGUMENTS: root as number power as long and nRadix of
// number.
//
// RETURN: None root is changed.
//
// DESCRIPTION: changes numeric representation of root to
// root ** power. Assumes nRadix is the nRadix of root.
//
//-----------------------------------------------------------------------------
void numpowlong( IN OUT PNUMBER *proot, IN long power,
IN unsigned long nRadix )
{
PNUMBER lret=NULL;
lret = longtonum( 1, nRadix );
while ( power > 0 )
{
if ( power & 1 )
{
mulnum( &lret, *proot, nRadix );
}
mulnum( proot, *proot, nRadix );
TRIMNUM(*proot);
power >>= 1;
}
destroynum( *proot );
*proot=lret;
}
//-----------------------------------------------------------------------------
//
// FUNCTION: ratpowlong
//
// ARGUMENTS: root as rational, power as long.
//
// RETURN: None root is changed.
//
// DESCRIPTION: changes rational representation of root to
// root ** power.
//
//-----------------------------------------------------------------------------
void ratpowlong( IN OUT PRAT *proot, IN long power )
{
if ( power < 0 )
{
// Take the positive power and invert answer.
PNUMBER pnumtemp = NULL;
ratpowlong( proot, -power );
pnumtemp = (*proot)->pp;
(*proot)->pp = (*proot)->pq;
(*proot)->pq = pnumtemp;
}
else
{
PRAT lret=NULL;
lret = longtorat( 1 );
while ( power > 0 )
{
if ( power & 1 )
{
mulnumx( &(lret->pp), (*proot)->pp );
mulnumx( &(lret->pq), (*proot)->pq );
}
mulrat( proot, *proot );
trimit(&lret);
trimit(proot);
power >>= 1;
}
destroyrat( *proot );
*proot=lret;
}
}
//-----------------------------------------------------------------------------
//
// FUNCTION: longlog10
//
// ARGUMENTS: number as long.
//
// RETURN: returns int(log10(abs(number)+1)), useful in formatting output
//
//-----------------------------------------------------------------------------
long longlognRadix( long x )
{
long ret = 0;
x--;
if ( x < 0 )
{
x = -x;
}
while ( x )
{
ret++;
x /= nRadix;
}
return( ret );
}