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C++

/* HMath: C++ high precision math routines
Copyright (C) 2004 Ariya Hidayat <ariya.hidayat@gmail.com>
2007 Helder Correia <helder.pereira.correia@gmail.com>
This program is free software; you can redistribute it and/or
modify it under the terms of the GNU General Public License
as published by the Free Software Foundation; either version 2
of the License, or (at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; see the file COPYING. If not, write to
the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
Boston, MA 02110-1301, USA.
*/
#include "hmath.h"
#include "number.h"
#include <ctype.h>
#include <stdlib.h>
#include <string.h>
#include <stdio.h>
#include <sstream>
#include <iostream>
// internal number of decimal digits
#define HMATH_MAX_PREC 150
// digits used for number comparison
// (not all are used, to work around propagated error problem)
#define HMATH_COMPARE_PREC 70
// maximum shown digits if prec is negative
#define HMATH_MAX_SHOWN 10
// from number.c, need to be freed somehow
extern bc_num _zero_;
extern bc_num _one_;
extern bc_num _two_;
class HNumberPrivate
{
public:
bc_num num;
bool nan;
char format;
};
void out_of_memory(void){
return;
}
void rt_warn(char * ,...){
return;
}
void rt_error(char * ,...){
return;
}
static bc_num h_create( int len = 1, int scale = 0 )
{
bc_num temp;
temp = (bc_num) malloc( sizeof(bc_struct) );
temp->n_sign = PLUS;
temp->n_len = len;
temp->n_scale = scale;
temp->n_refs = 1;
temp->n_ptr = (char*) malloc( len+scale+1 );
temp->n_value = temp->n_ptr;
temp->n_next = 0;
memset (temp->n_ptr, 0, len+scale+1);
return temp;
}
static void h_destroy( bc_num n )
{
free( n->n_ptr );
free( n );
}
// reclaim and free one bc_num from the freelist
// workaround for number.c, because it doesn't really free a number
// but instead put it in the pool of unused numbers
// this function will take it back from that pool and set it really free
static void h_grabfree()
{
bc_num t = bc_new_num( 1, 0 );
h_destroy( t );
}
// make an exact (explicit) copy
static bc_num h_copy( bc_num n )
{
int len = n->n_len;
int scale = n->n_scale;
bc_num result = h_create( len, scale );
memcpy( result->n_ptr, n->n_value, len+scale+1 );
result->n_sign = n->n_sign;
result->n_value = result->n_ptr;
h_grabfree();
return result;
}
// same as copy, but readjust decimal digits
static bc_num h_rescale( bc_num n, int sc )
{
int len = n->n_len;
int scale = MIN( sc, n->n_scale );
bc_num result = h_create( len, scale );
memcpy( result->n_ptr, n->n_value, len+scale+1 );
result->n_sign = n->n_sign;
result->n_value = result->n_ptr;
h_grabfree();
return result;
}
// add two numbers, return newly allocated number
static bc_num h_add( bc_num n1, bc_num n2 )
{
bc_num r = h_create();
bc_add( n1, n2, &r, 1 );
h_grabfree();
return r;
}
// multiply two numbers, return newly allocated number
static bc_num h_mul( bc_num n1, bc_num n2 )
{
bc_num r = h_create();
bc_multiply( n1, n2, &r, HMATH_MAX_PREC );
h_grabfree();
return r;
}
enum Base {Decimal, Hexadec, Octal, Binary};
static bool isValidDigit(const char c, const Base b)
{
switch (b)
{
case Hexadec:
return ((c >= '0' && c <= '9') || (c >= 'A' && c < 'G') || (c >= 'a' && c < 'g'));
case Octal:
return (c >= '0' && c < '8');
case Binary:
return ( c == '0' || c == '1' );
case Decimal:
default:
break;
}
return (c >= '0' && c <= '9');
}
// convert simple string to number
static bc_num h_str2num( const char* str, int scale = HMATH_MAX_PREC )
{
int digits, strscale;
const char *ptr;
char *nptr;
bool zero_int;
/* Check for valid number and count digits. */
ptr = str;
digits = 0;
strscale = 0;
zero_int = false;
Base base = Decimal;
if (*ptr == '+' || *ptr == '-') ptr++; /* Sign */
if ( *ptr == '0' ) //leadeing 0, could be hexadec etc.
{
ptr++;
if (*ptr == 'x') { base = Hexadec; ptr++; }
else if (*ptr == 'o') { base = Octal; ptr++; }
else if (*ptr == 'b') { base = Binary; ptr++; }
else if (*ptr == 'd') ptr++;
}
while (*ptr == '0') ptr++; /* Skip leading zeros. */
while (isValidDigit((int)*ptr, base)) ptr++, digits++; /* digits, maybe non decimal base */
if (*ptr == '.') { if (base == Decimal) ptr++; else return h_create(); } /* decimal point */
while (isdigit((int)*ptr)) ptr++, strscale++; /* digits, must be decimal, we had a period ; */
if ((*ptr != '\0') || (digits+strscale == 0))
return h_create();
bc_num num;
switch (base)
{
case Hexadec:
{
int chr;
bc_num _16 = h_create(); bc_int2num( &_16, 16 );
bc_num factor = h_create(); bc_int2num( &factor, 1 );
bc_num tmp1, tmp2;
num = h_create(); bc_int2num( &num, 0 );
for (;digits > 0; --digits) // n = n+f*x;
{
--ptr;
chr = CH_HEX(*ptr);
if (chr) // skip increment if digit is '0'
{
tmp1 = h_create();
bc_int2num( &tmp1, chr ); // x
tmp2 = h_mul( factor, tmp1 ); // f*x
h_destroy( tmp1 );
tmp1 = h_add( num, tmp2 ); // n+f*x;
h_destroy( num ); h_destroy( tmp2 );
num = h_copy( tmp1 ); // n = n+f*x;
h_destroy( tmp1 );
}
tmp1 = h_mul( factor, _16 ); // f*16
h_destroy( factor );
factor = h_copy( tmp1 ); // f = f*16;
h_destroy( tmp1 );
}
if (*str == '-') num->n_sign = MINUS; else num->n_sign = PLUS;
break;
}
case Octal:
{
int chr;
bc_num _8 = h_create(); bc_int2num( &_8, 8 );
bc_num factor = h_create(); bc_int2num( &factor, 1 );
bc_num tmp1, tmp2;
num = h_create(); bc_int2num( &num, 0 );
for (;digits > 0; --digits) // n = n+f*x;
{
--ptr;
chr = CH_VAL(*ptr);
if (chr) // skip increment if digit is '0'
{
tmp1 = h_create();
bc_int2num( &tmp1, chr ); // x
tmp2 = h_mul( factor, tmp1 ); // f*x
h_destroy( tmp1 );
tmp1 = h_add( num, tmp2 ); // n+f*x;
h_destroy( num ); h_destroy( tmp2 );
num = h_copy( tmp1 ); // n = n+f*x;
h_destroy( tmp1 );
}
tmp1 = h_mul( factor, _8 ); // f*8
h_destroy( factor );
factor = h_copy( tmp1 ); // f = f*8;
h_destroy( tmp1 );
}
if (*str == '-') num->n_sign = MINUS; else num->n_sign = PLUS;
break;
}
case Binary:
{
bc_num _2 = h_create(); bc_int2num( &_2, 2 );
bc_num factor = h_create(); bc_int2num( &factor, 1 );
bc_num tmp;
num = h_create(); bc_int2num( &num, 0 );
for (;digits > 0; --digits) // n = n+f;
{
--ptr;
if (CH_VAL(*ptr)) // only increment if bit is set
{
tmp = h_add( num, factor ); // n+f;
h_destroy( num ); num = h_copy( tmp ); // n = n+f;
h_destroy( tmp );
}
tmp = h_mul( factor, _2 ); // f*2
factor = h_copy( tmp ); // f = f*2;
h_destroy( tmp );
}
if (*str == '-') num->n_sign = MINUS; else num->n_sign = PLUS;
break;
}
case Decimal:
default:
{
/* Adjust numbers and allocate storage and initialize fields. */
strscale = MIN(strscale, scale);
if (digits == 0)
{
zero_int = true;
digits = 1;
}
num = h_create( digits, strscale );
ptr = str;
if (*ptr == '-')
{
num->n_sign = MINUS;
ptr++;
}
else
{
num->n_sign = PLUS;
if (*ptr == '+') ptr++;
}
while (*ptr == '0') ptr++;
nptr = num->n_value;
if (zero_int)
{
*nptr++ = 0;
digits = 0;
}
for (;digits > 0; digits--)
*nptr++ = (char)CH_VAL(*ptr++);
if (strscale > 0)
{
ptr++;
for (;strscale > 0; strscale--)
*nptr++ = (char)CH_VAL(*ptr++);
}
}
}
return num;
}
// subtract two numbers, return newly allocated number
static bc_num h_sub( bc_num n1, bc_num n2 )
{
bc_num r = h_create();
bc_sub( n1, n2, &r, 1 );
h_grabfree();
return r;
}
// divide two numbers, return newly allocated number
static bc_num h_div( bc_num n1, bc_num n2 )
{
bc_num r = h_create();
bc_divide( n1, n2, &r, HMATH_MAX_PREC );
h_grabfree();
return r;
}
// find 10 raise to num
// e.g.: when num is 5, it results 100000
static bc_num h_raise10( int n )
{
// calculate proper factor
int len = abs(n)+2;
char* sf = new char[len+1];
sf[len] = '\0';
if( n >= 0 )
{
sf[0] = '1';
sf[len-1] = '\0';
sf[len-2] = '\0';
for( int i = 0; i < n; i++ )
sf[i+1] = '0';
}
else
{
sf[0] = '0'; sf[1] = '.';
for( int i = 0; i < -n; i++ )
sf[i+2] = '0';
sf[len-1] = '1';
}
bc_num factor = h_str2num( sf, abs(n) );
delete[] sf;
return factor;
}
// round up to certain decimal digits
static bc_num h_round( bc_num n, int prec )
{
// no need to round?
if( prec >= n->n_scale )
return h_copy( n );
// example: rounding "3.14159" to 4 decimal digits means
// adding 0.5e-4 to 3.14159, it becomes 3.14164
// taking only 4 decimal digits, so it's now 3.1416
if( prec < 0 ) prec = 0;
bc_num x = h_raise10( -prec-1 );
bc_num y = 0;
bc_int2num( &y, 5 );
bc_num z = h_mul( x, y );
z->n_sign = n->n_sign;
bc_num r = h_add( n, z );
h_destroy( x );
h_destroy( y );
h_destroy( z );
// only digits we are interested in
bc_num v = h_rescale( r, prec );
h_destroy( r );
return v;
}
// trunc up to certain decimal digits
static bc_num h_trunc( bc_num n, int prec )
{
// no need to truncate?
if( prec >= n->n_scale )
return h_copy( n );
if( prec < 0 )
prec = 0;
// only digits we are interested in
bc_num v = h_rescale( n, prec );
return v;
}
// remove trailing zeros
static void h_trimzeros( bc_num num )
{
while( ( num->n_scale > 0 ) && ( num->n_len+num->n_scale > 0 ) )
if( num->n_value[num->n_len+num->n_scale-1] == 0 )
num->n_scale--;
else break;
}
static void h_init()
{
static bool h_initialized = false;
if( !h_initialized )
{
h_initialized = true;
bc_init_numbers();
}
}
HNumber::HNumber(): d(0)
{
h_init();
d = new HNumberPrivate;
d->nan = false;
d->format = 0;
d->num = h_create();
}
HNumber::HNumber( const HNumber& hn ): d(0)
{
h_init();
d = new HNumberPrivate;
d->nan = false;
d->num = h_create();
operator=( hn );
}
HNumber::HNumber( int i ): d(0)
{
h_init();
d = new HNumberPrivate;
d->nan = false;
d->num = h_create();
d->format = 0;
bc_int2num( &d->num, i );
}
HNumber::HNumber( const char* str ): d(0)
{
h_init();
d = new HNumberPrivate;
d->nan = false;
d->num = h_create();
d->format = 0;
if( str )
if( strlen(str) == 3 )
if( tolower(str[0])=='n' )
if( tolower(str[1])=='a' )
if( tolower(str[2])=='n' )
d->nan = true;
if( str && !d->nan )
{
char* s = new char[ strlen(str)+1 ];
strcpy( s, str );
bool isHex = false, isDecimal = true;
char* p = s;
for( ;; p++ )
{
if (*p == 'x' && *(p-1) == '0')
{
isHex = true;
isDecimal = false;
continue;
}
if ((*p == 'b' || *p == 'o') && *(p-1) == '0')
{
isDecimal = false;
continue;
}
if( *p != '+' )
if( *p != '-' )
if( *p != '.' )
if( !isdigit(*p) )
if(!(isHex && *p >= 'a' && *p < 'g'))
break;
}
int expd = 0;
if (isDecimal)
{
if( ( *p == 'e' ) || ( *p == 'E' ) )
{
*p = '\0';
expd = atoi( p+1 );
}
}
h_destroy( d->num );
d->num = h_str2num( s );
delete [] s;
if (isDecimal)
{
if( expd >= HMATH_MAX_PREC ) // too large
{
d->nan = true;
}
else
if( expd <= -HMATH_MAX_PREC ) // too small
{
d->nan = true;
}
else
if( expd != 0 )
{
bc_num factor = h_raise10( expd );
bc_num nn = h_copy( d->num );
h_destroy( d->num );
d->num = h_mul( nn, factor );
h_destroy( nn );
h_destroy( factor );
}
}
h_trimzeros( d->num );
}
}
HNumber::~HNumber()
{
h_destroy( d->num );
delete d;
}
bool HNumber::isNan() const
{
return d->nan;
}
bool HNumber::isZero() const
{
return !d->nan && ( bc_is_zero( d->num )!=0 );
}
bool HNumber::isPositive() const
{
return !d->nan && !isNegative() && !isZero();
}
bool HNumber::isNegative() const
{
return !d->nan && ( bc_is_neg( d->num )!=0 );
}
bool HNumber::isInteger() const
{
return *this == HMath::integer( *this );
}
char HNumber::format() const
{
return d->format;
}
void HNumber::setFormat(char c) const
{
d->format = d->nan?0:c;
}
HNumber HNumber::nan()
{
HNumber n;
n.d->nan = true;
return n;
}
int HNumber::toInt()
{
char* str = HMath::formatFixed( *this );
std::string s( str );
delete[] str;
std::istringstream iss( s );
int i;
iss >> i;
return i;
}
HNumber& HNumber::operator=( const HNumber& hn )
{
d->nan = hn.d->nan;
h_destroy( d->num );
d->num = h_copy( hn.d->num );
d->format = hn.format();
return *this;
}
HNumber HNumber::operator+( const HNumber& num ) const
{
if( isNan() ) return HNumber( *this );
if( num.isNan() ) return HNumber( num );
HNumber result;
h_destroy( result.d->num );
result.d->num = h_add( d->num, num.d->num );
return result;
}
HNumber& HNumber::operator+=( const HNumber& num )
{
HNumber n = HNumber(*this) + num;
operator=( n );
return *this;
}
HNumber HNumber::operator-( const HNumber& num ) const
{
if( isNan() ) return HNumber( *this );
if( num.isNan() ) return HNumber( num );
HNumber result;
h_destroy( result.d->num );
result.d->num = h_sub( d->num, num.d->num );
return result;
}
HNumber& HNumber::operator-=( const HNumber& num )
{
HNumber n = HNumber(*this) - num;
operator=( n );
return *this;
}
HNumber HNumber::operator*( const HNumber& num ) const
{
if( isNan() ) return HNumber( *this );
if( num.isNan() ) return HNumber( num );
HNumber result;
h_destroy( result.d->num );
result.d->num = h_mul( d->num, num.d->num );
return result;
}
HNumber& HNumber::operator*=( const HNumber& num )
{
HNumber n = HNumber(*this) * num;
operator=( n );
return *this;
}
HNumber HNumber::operator/( const HNumber& num ) const
{
if( isNan() ) return HNumber( *this );
if( num.isNan() ) return HNumber( num );
if( num == 0 ) return HNumber::nan();
HNumber result;
h_destroy( result.d->num );
result.d->num = h_div( d->num, num.d->num );
return result;
}
HNumber& HNumber::operator/=( const HNumber& num )
{
HNumber n = HNumber(*this) / num;
operator=( n );
return *this;
}
HNumber HNumber::operator%( const HNumber& num ) const
{
if( isNan() ) return HNumber( *this );
if( num.isNan() ) return HNumber( num );
HNumber result;
bc_modulo (d->num, num.d->num, &result.d->num, 0);
return result;
}
bool HNumber::operator>( const HNumber& n ) const
{
return HMath::compare( *this, n ) > 0;
}
bool HNumber::operator<( const HNumber& n ) const
{
return HMath::compare( *this, n ) < 0;
}
bool HNumber::operator>=( const HNumber& n ) const
{
return HMath::compare( *this, n ) >= 0;
}
bool HNumber::operator<=( const HNumber& n ) const
{
return HMath::compare( *this, n ) <= 0;
}
bool HNumber::operator==( const HNumber& n ) const
{
return HMath::compare( *this, n ) == 0;
}
bool HNumber::operator!=( const HNumber& n ) const
{
return HMath::compare( *this, n ) != 0;
}
// format number in engineering notation
char* HMath::formatEngineering( const HNumber& hn, int prec )
{
if( hn.isNan() )
{
char* str = (char*)malloc( 4 );
str[0] = 'N';
str[1] = 'a';
str[2] = 'N';
str[3] = '\0';
return str;
}
int nIntDigs = hn.d->num->n_len;
int nFracDigs = hn.d->num->n_scale;
char * digs = hn.d->num->n_value;
int tenExp;
// find the exponent and the factor
int tzeros = 0;
for( int c=0; c<hn.d->num->n_len+hn.d->num->n_scale; c++, tzeros++ )
if( hn.d->num->n_value[c]!= 0 ) break;
int expd = hn.d->num->n_len - tzeros - 1;
if ( hn >= 1 || hn <= -1 )
{
// point must be shifted to the left, if needed
if ( nIntDigs % 3 == 0 )
{
// 3n digits to the left
if ( hn > 999 || hn < -999 )
// n > 1
tenExp = nIntDigs - 3;
else
// n = 1
tenExp = 0;
}
else
// non-3n digits to the left
tenExp = nIntDigs - nIntDigs % 3;
}
else
{
// point must be shifted to the right
// find first non-zero digit to the right of the point
int startDigIdx = nIntDigs;
int endDigIdx = nIntDigs + nFracDigs - 1;
int idx;
for ( idx = startDigIdx; idx <= endDigIdx; idx++ )
if ( digs[idx] != 0 )
break;
// calculate exponent to shift right
while ( idx % 3 != 0 )
idx++;
tenExp = -idx;
}
// scale the number by a new factor
HNumber nn = hn * HMath::raise( 10, -tenExp );
// too close to zero?
if( hn.isZero() || ( expd <= -HMATH_COMPARE_PREC ) )
{
nn = HNumber( 0 );
tenExp = 0;
}
// build result expression string with E notation
char* str = formatFixed( nn, prec );
std::string resString = std::string( str ) + "e";
free( str );
std::stringstream ss;
ss << tenExp;
resString += ss.str();
char * result = (char *) malloc( resString.size() + 1 );
strcpy( result, resString.c_str() );
return result;
}
// format number with fixed number of decimal digits
char* HMath::formatFixed( const HNumber& hn, int prec )
{
if( hn.isNan() )
{
char* str = (char*)malloc( 4 );
str[0] = 'N';
str[1] = 'a';
str[2] = 'N';
str[3] = '\0';
return str;
}
bc_num n = h_copy( hn.d->num );
h_trimzeros( n );
int oprec = prec;
if( prec < 0 )
{
prec = HMATH_MAX_SHOWN;
if( n->n_scale < HMATH_MAX_SHOWN )
prec = n->n_scale;
}
// yes, this is necessary!
bc_num m = h_round( n, prec );
h_trimzeros( m );
h_destroy( n );
n = m;
if( oprec < 0 )
{
prec = HMATH_MAX_SHOWN;
if( n->n_scale < HMATH_MAX_SHOWN )
prec = n->n_scale;
}
// how many to allocate?
int len = n->n_len + prec;
if( n->n_sign != PLUS ) len++;
if( prec > 0 ) len++;
char* str = (char*)malloc( len+1 );
char* p = str;
// the sign and the integer part
// but avoid printing "-0"
if( n->n_sign != PLUS )
if( !bc_is_zero( n ) ) *p++ = '-';
for( int c=0; c<n->n_len; c++ )
*p++ = (char)BCD_CHAR( n->n_value[c] );
// the fraction part
if( prec > 0 )
{
*p++ = '.';
int k = (prec < n->n_scale) ? prec : n->n_scale;
for( int d=0; d<k; d++ )
*p++ = (char)BCD_CHAR( n->n_value[n->n_len+d] );
for( int r=n->n_scale; r<prec; r++ )
*p++ = '0';
}
*p = '\0';
h_destroy( n );
return str;
}
// format number in scientific notation
char* HMath::formatScientific( const HNumber& hn, int prec )
{
if( hn.isNan() )
{
char* str = (char*)malloc( 4 );
str[0] = 'N';
str[1] = 'a';
str[2] = 'N';
str[3] = '\0';
return str;
}
// find the exponent and the factor
int tzeros = 0;
for( int c=0; c<hn.d->num->n_len+hn.d->num->n_scale; c++, tzeros++ )
if( hn.d->num->n_value[c]!= 0 ) break;
int expd = hn.d->num->n_len - tzeros - 1;
// extra digits needed for the exponent part
int expn = 0;
for( int e = ::abs(expd); e > 0; e/=10 ) expn++;
if( expd <= 0 ) expn++;
// scale the number by a new factor
HNumber nn = hn * HMath::raise( 10, -expd );
// too close to zero?
if( hn.isZero() || ( expd <= -HMATH_COMPARE_PREC ) )
{
nn = HNumber(0);
expd = 0;
expn = 1;
}
char* str = formatFixed( nn, prec );
char* result = (char*) malloc( strlen(str)+expn+2 );
strcpy( result, str );
free( str );
// the exponential part
char* p = result + strlen(result);
*p++ = 'e'; p[expn] = '\0';
if( expd < 0 ) *p = '-';
for( int k=expn; k>0; k-- )
{
int digit = expd % 10;
p[k-1] = (char)('0' + ::abs( digit ));
expd = expd / 10;
if( expd == 0 ) break;
}
return result;
}
char* HMath::formatGeneral( const HNumber& hn, int prec )
{
if( hn.isNan() )
{
char* str = (char*)malloc( 4 );
str[0] = 'N';
str[1] = 'a';
str[2] = 'N';
str[3] = '\0';
return str;
}
// find the exponent and the factor
int tzeros = 0;
for( int c=0; c<hn.d->num->n_len+hn.d->num->n_scale; c++, tzeros++ )
if( hn.d->num->n_value[c]!= 0 ) break;
int expd = hn.d->num->n_len - tzeros - 1;
char* str;
if( expd > 5 )
str = formatScientific( hn, prec );
else if( ( expd < -4 ) && (expd>-HMATH_COMPARE_PREC ) )
str = formatScientific( hn, prec );
else if ( (expd < 0) && (prec>0) && (expd < -prec) )
str = formatScientific( hn, prec );
else
str = formatFixed( hn, prec );
return str;
}
char* HMath::formatHexadec( const HNumber& hn )
{
char* str;
if( hn.isNan() || !hn.isInteger())
{
str = (char*)malloc( 4 );
str[0] = 'N';
str[1] = 'a';
str[2] = 'N';
str[3] = '\0';
return str;
}
int digits = 1; HNumber _16(16);
bool negative = (hn < 0);
HNumber tmp = negative ? HNumber(0)-hn : hn;
while (integer(tmp/=_16) > 0) ++digits; // how many digits
str = (char*)malloc( digits+3+negative );
char* ptr = &str[digits+2+negative]; *ptr = '\0';
HNumber val;
int i;
tmp = negative ? HNumber(0)-hn : hn;
HNumber f;
HNumber f_old(1);
while (digits--)
{
f = f_old*_16;
val = tmp % (f); tmp -= val;
val /= f_old; f_old = f; i = bc_num2long( val.d->num);
*--ptr = (i < 10) ? '0'+i : 'A'+i-10;
}
*--ptr = 'x'; *--ptr = '0'; if (negative) *--ptr = '-';
return str;
}
char* HMath::formatOctal( const HNumber& hn )
{
char* str;
if( hn.isNan() || !hn.isInteger())
{
str = (char*)malloc( 4 );
str[0] = 'N';
str[1] = 'a';
str[2] = 'N';
str[3] = '\0';
return str;
}
int digits = 1; HNumber _8(8);
bool negative = (hn < 0);
HNumber tmp = negative ? HNumber(0)-hn : hn;
while (integer(tmp/=_8) > 0) ++digits; // how many digits
str = (char*)malloc( digits+3+negative );
char* ptr = &str[digits+2+negative]; *ptr = '\0';
HNumber val;
tmp = negative ? HNumber(0)-hn : hn;
HNumber f;
HNumber f_old(1);
while (digits--)
{
f = f_old*_8;
val = tmp % (f); tmp -= val;
val /= f_old; f_old = f;
*--ptr = '0'+bc_num2long( val.d->num);
}
*--ptr = 'o'; *--ptr = '0'; if (negative) *--ptr = '-';
return str;
}
char* HMath::formatBinary( const HNumber& hn )
{
char* str;
if( hn.isNan() || !hn.isInteger())
{
str = (char*)malloc( 4 );
str[0] = 'N';
str[1] = 'a';
str[2] = 'N';
str[3] = '\0';
return str;
}
int digits = 1; HNumber _2(2);
bool negative = (hn < 0);
HNumber tmp = negative ? HNumber(0)-hn : hn;
while (integer(tmp/=_2) > 0) ++digits; // how many digits
str = (char*)malloc( digits+3+negative );
char* ptr = &str[digits+2+negative]; *ptr = '\0';
HNumber val;
HNumber _0(0);
tmp = negative ? _0-hn : hn;
HNumber f;
HNumber f_old(1);
while (digits--)
{
f = f_old*_2;
val = tmp % (f); tmp -= val;
val /= f_old; f_old = f;
*--ptr = (val == _0) ?'0':'1';
}
*--ptr = 'b'; *--ptr = '0'; if (negative) *--ptr = '-';
return str;
}
char* HMath::format( const HNumber& hn, char format, int prec )
{
if( hn.isNan() )
{
char* str = (char*)malloc( 4 );
str[0] = 'N';
str[1] = 'a';
str[2] = 'N';
str[3] = '\0';
return str;
}
if ( format=='g' ) return formatGeneral ( hn, prec );
else if( format=='f' ) return formatFixed ( hn, prec );
else if( format=='n' ) return formatEngineering( hn, prec );
else if( format=='e' ) return formatScientific ( hn, prec );
else if( format=='h' ) return formatHexadec ( hn );
else if( format=='o' ) return formatOctal ( hn );
else if( format=='b' ) return formatBinary ( hn );
// fallback to 'g'
return formatGeneral( hn, prec );
}
HNumber HMath::phi()
{
return HNumber("1.61803398874989484820458683436563811772030917980576"
"28621354486227052604628189024497072072041893911374"
"84754088075386891752126633862223536931793180060766"
"72635443338908659593958290563832266131992829026788"
"06752087668925017116962070322210432162695486262963"
"13614438149758701220340805887954454749246185695364"
"86444924104432077134494704956584678850987433944221"
"25448770664780915884607499887124007652170575179788"
"34166256249407589069704000281210427621771117778053"
"15317141011704666599146697987317613560067087480710"
"13179523689427521948435305678300228785699782977834"
"78458782289110976250030269615617002504643382437764"
"86102838312683303724292675263116533924731671112115"
"88186385133162038400522216579128667529465490681131"
"71599343235973494985090409476213222981017261070596"
"11645629909816290555208524790352406020172799747175"
"34277759277862561943208275051312181562855122248093"
"94712341451702237358057727861600868838295230459264"
"78780178899219902707769038953219681986151437803149"
"97411069260886742962267575605231727775203536139362");
}
HNumber HMath::pi()
{
return HNumber("3.14159265358979323846264338327950288419716939937510"
"58209749445923078164062862089986280348253421170679"
"82148086513282306647093844609550582231725359408128"
"48111745028410270193852110555964462294895493038196"
"44288109756659334461284756482337867831652712019091"
"45648566923460348610454326648213393607260249141273"
"72458700660631558817488152092096282925409171536436"
"78925903600113305305488204665213841469519415116094"
"33057270365759591953092186117381932611793105118548"
"07446237996274956735188575272489122793818301194912"
"98336733624406566430860213949463952247371907021798"
"60943702770539217176293176752384674818467669405132"
"00056812714526356082778577134275778960917363717872"
"14684409012249534301465495853710507922796892589235"
"42019956112129021960864034418159813629774771309960"
"51870721134999999837297804995105973173281609631859"
"50244594553469083026425223082533446850352619311881"
"71010003137838752886587533208381420617177669147303"
"59825349042875546873115956286388235378759375195778"
"1857780532171226806613001927876611195909216420198" );
}
HNumber HMath::add( const HNumber& n1, const HNumber& n2 )
{
HNumber result = n1 + n2;
return result;
}
HNumber HMath::sub( const HNumber& n1, const HNumber& n2 )
{
HNumber result = n1 - n2;
return result;
}
HNumber HMath::mul( const HNumber& n1, const HNumber& n2 )
{
HNumber result = n1 * n2;
return result;
}
HNumber HMath::div( const HNumber& n1, const HNumber& n2 )
{
HNumber result = n1 / n2;
return result;
}
int HMath::compare( const HNumber& n1, const HNumber& n2 )
{
if( n1.isNan() && n2.isNan() ) return 0;
HNumber delta = sub( n1, n2 );
delta = HMath::round( delta, HMATH_COMPARE_PREC );
if( delta.isZero() ) return 0;
else if( delta.isNegative() ) return -1;
return 1;
}
HNumber HMath::max( const HNumber& n1, const HNumber& n2 )
{
if ( n1.isNan() || n2.isNan() )
return HNumber::nan();
if ( n1 >= n2 )
return n1;
else
return n2;
}
HNumber HMath::min( const HNumber& n1, const HNumber& n2 )
{
if ( n1.isNan() || n2.isNan() )
return HNumber::nan();
if ( n1 <= n2 )
return n1;
else
return n2;
}
HNumber HMath::abs( const HNumber& n )
{
HNumber r( n );
r.d->num->n_sign = PLUS;
return r;
}
HNumber HMath::negate( const HNumber& n )
{
if( n.isNan() || n.isZero() )
return HNumber( n );
HNumber result( n );
result.d->num->n_sign = ( n.d->num->n_sign == PLUS ) ? MINUS : PLUS;
return result;
}
HNumber HMath::round( const HNumber& n, int prec )
{
if( n.isNan() )
return HNumber::nan();
HNumber result;
h_destroy( result.d->num );
result.d->num = h_round( n.d->num, prec );
return result;
}
HNumber HMath::trunc( const HNumber& n, int prec )
{
if( n.isNan() )
return HNumber::nan();
HNumber result;
h_destroy( result.d->num );
result.d->num = h_trunc( n.d->num, prec );
return result;
}
HNumber HMath::integer( const HNumber& n )
{
if( n.isNan() )
return HNumber::nan();
if( n.isZero() )
return HNumber( 0 );
HNumber result;
h_destroy( result.d->num );
result.d->num = h_rescale( n.d->num, 0 );
return result;
}
HNumber HMath::frac( const HNumber& n )
{
if( n.isNan() )
return HNumber::nan();
return n - integer(n);
}
HNumber HMath::floor( const HNumber& n )
{
if( n.isNan() )
return HNumber::nan();
if( n.isInteger() )
return n;
else if( n.isPositive() )
return n - frac(n);
else
return n - HNumber(1) - frac(n);
}
HNumber HMath::ceil( const HNumber& n )
{
if( n.isNan() )
return HNumber::nan();
if( n.isInteger() )
return n;
else if( n.isPositive() )
return n + HNumber(1) - frac(n);
else
return n - frac(n);
}
HNumber HMath::gcd( const HNumber& n1, const HNumber& n2 )
{
if( n1.isNan() || n2.isNan() )
return HNumber::nan();
HNumber a = abs( n1 );
HNumber b = abs( n2 );
if ( a == 0 )
return b;
if ( b == 0 )
return a;
// run Euclidean algorithm
while ( true )
{
a = a % b;
if ( a == 0 )
return b;
b = b % a;
if ( b == 0 )
return a;
}
}
HNumber HMath::sqrt( const HNumber& n )
{
if( n.isNan() )
return HNumber::nan();
if( n.isZero() )
return n;
if( n.isNegative() )
return HNumber::nan();
// useful constant
HNumber half("0.5");
// Use Netwon-Raphson algorithm
HNumber r( 1 );
for( int i = 0; i < HMATH_MAX_PREC; i++ )
{
HNumber q = n / r;
if( r == q ) break;
HNumber s = r + q;
r = s * half;
}
return r;
}
HNumber HMath::cbrt( const HNumber& n )
{
if( n.isNan() )
return HNumber::nan();
if( n.isZero() )
return n;
// useful constants
HNumber three = HNumber("3");
HNumber twoThirds = HNumber("2") / three;
// iterations to approximate result
// X[i+1] = (2/3)X[i] + n / (3 * X[i]^2))
// initial guess = sqrt( n )
// r = X[i], q = X[i+1], a = n
HNumber a = n.isNegative() ? n * HNumber("-1") : n;
HNumber r = sqrt( a );
for( int i = 0; i < HMATH_MAX_PREC; i++ )
{
HNumber q = (twoThirds * r) + (a / (three * r * r));
if( r == q )
break;
r = q;
}
if( n.isNegative())
return r * HNumber("-1");
else
return r;
}
HNumber HMath::raise( const HNumber& n1, int n )
{
if( n1.isNan() ) return n1;
// http://en.wikipedia.org/wiki/Exponentiation#Powers_of_zero
if( n1.isZero() )
{
if( n < 0 )
return HNumber::nan();
if( n > 0 )
return HNumber(0);
// debatable, see http://en.wikipedia.org/wiki/Empty_product#0_raised_to_the_0th_power
// vs http://mathworld.wolfram.com/Power.html
if( n == 0 )
return HNumber(1);
}
if( n1 == HNumber(1) ) return n1;
if( n == 0 ) return HNumber(1);
if( n == 1 ) return n1;
if(n > 0)
{
// squaring algorithm to find exponentiation
// see http://en.wikipedia.org/wiki/Exponentiation_by_squaring
HNumber result = HNumber(1);
HNumber x = n1;
while(n > 0)
{
if(n & 1)
{
result = result * x;
n--;
}
x = x * x;
n = n >> 1;
}
return result;
}
HNumber result = n1;
for( ; n < 1; n++ )
result /= n1;
return result;
}
HNumber HMath::raise( const HNumber& n1, const HNumber& n2 )
{
if( n1.isNan() ) return HNumber::nan();
if( n2.isNan() ) return HNumber::nan();
// see previous function
if( n1.isZero() )
{
if( n2.isNegative() )
return HNumber::nan();
if( n2.isPositive() )
return HNumber(0);
if( n2.isZero() )
return HNumber(1);
}
if( n1 == HNumber(1) ) return n1;
if( n2.isZero() ) return HNumber(1);
if( n2 == HNumber(1) ) return n1;
HNumber result;
// n1 is negative, n2 must be integer
if( n1.isNegative() )
{
if( HMath::integer(n2) != n2)
result = HNumber::nan();
else
{
// use integer raise function
HNumber nn = n2;
result = raise( n1, atoi( HMath::formatFixed(nn, 0) ) );
}
}
else
{
// n2 integer? use the integer raise version
if( HMath::integer(n2) == n2)
{
// use integer raise function
HNumber nn = n2;
result = raise( n1, atoi( HMath::formatFixed(nn, 0) ) );
}
else
{
// x^y = exp( y*ln(x) )
result = n2 * HMath::ln(n1);
result = HMath::exp( result );
}
}
return result;
}
HNumber HMath::exp( const HNumber& x )
{
if( x.isNan() )
return HNumber::nan();
bool negative = x.isNegative();
HNumber xs = HMath::abs( x );
// adjust so that x is less than 1
// use the fact that e^x = (e^(x/2))^2
HNumber one(1);
HNumber half("0.5");
unsigned factor = 0;
while( xs > one )
{
factor ++;
xs = xs * half;
}
// Taylor expansion: e^x = 1 + x + x^2/2! + x^3/3! + ...
HNumber num = xs;
HNumber den = 1;
HNumber sum = xs + 1;
// now loop to sum the series
for( int i = 2; i < HMATH_MAX_PREC; i++ )
{
num *= xs;
den *= HNumber(i);
if( num.isZero() ) break;
HNumber s = HMath::div( num, den );
if( s.isZero() ) break;
sum += s;
}
HNumber result = sum;
if( factor > 0 )
while( factor > 0 )
{
factor--;
result *= result;
}
if( negative )
result = HMath::div( HNumber(1), result );
return result;
};
HNumber HMath::ln( const HNumber& x )
{
if ( x.isNan() || x <= 0 )
return HNumber::nan();
// short circuit
if( x == HNumber(10) )
return HNumber("2.30258509299404568401799145468436420760110148862877"
"29760333279009675726102948650438303813865953227795"
"49054520440916779445247118780973037711833599749301"
"72118016928228381938415404059160910960135436620869" );
// useful constants
HNumber two(2);
HNumber one(1);
HNumber half("0.5");
// adjust so that x is between 0.5 and 2.0
// use the fact that ln(x^2) = 2*ln(x)
HNumber xs( x );
unsigned factor = 2;
while( xs >= two )
{
factor *= 2;
xs = HMath::sqrt( xs );
}
while( xs <= half )
{
factor *= 2;
xs = HMath::sqrt( xs );
}
// Taylor expansion: ln(x) = 2(a+a^3/3+a^5/5+...)
// where a=(x-1)/(x+1)
HNumber p = xs - 1;
HNumber q = xs + 1;
HNumber a = p / q;
HNumber as = a*a;
HNumber t = a;
HNumber sum = a;
// loop for the series (limited to avoid nasty cases)
for( int i = 3; i < HMATH_MAX_PREC; i+= 2 )
{
t *= as;
if( t.isZero() ) break;
HNumber s = HMath::div( t, HNumber(i) );
if( s.isZero() ) break;
sum += s;
}
HNumber result = sum * HNumber( factor );
return result;
}
HNumber HMath::log( const HNumber& x )
{
if ( x.isNan() || x <= 0 )
return HNumber::nan();
return HMath::ln( x ) / HMath::ln(10);
}
HNumber HMath::lg( const HNumber& x )
{
if ( x.isNan() || x <= 0 )
return HNumber::nan();
return HMath::ln( x ) / HMath::ln(2);
}
// ensure angle is within 0 to 2*pi
// useful for sin, cos
static HNumber simplifyAngle( const HNumber& x )
{
if( x.isNan() )
return HNumber::nan();
#if 1
// using simple method
HNumber pi2 = HMath::pi() * 2;
HNumber nn = x / pi2;
HNumber xs = x - HMath::integer(nn)*pi2;
if( xs.isNegative() ) xs += pi2;
return xs;
#else
// using argument reduction method
// see http://www.derekroconnor.net/Software/Ng--ArgReduction.pdf
HNumber factor = HNumber(2) / HMath::pi();
HNumber y = x * factor;
HNumber f = HMath::frac(y);
HNumber r = f * HMath::pi()/HNumber(2);
// find int(y) mod 4
HNumber n = HMath::integer( y );
HNumber m = n - HNumber(4)*HMath::integer( n / HNumber(4) );
HNumber halfpi = HMath::pi() / HNumber(2);
if(m == HNumber(1))
r += halfpi;
if(m == HNumber(2))
r += HMath::pi();
if(m == HNumber(3))
r += halfpi + HMath::pi();
return r;
#endif
}
HNumber HMath::sin( const HNumber& x )
{
if( x.isNan() )
return HNumber::nan();
// adjust to small angle for speedup
HNumber xs = simplifyAngle( x );
// limits shortcut
if ( x == 0 || x == HMath::pi() || x == HMath::pi() * 2 )
return HNumber( 0 );
else if( x == HMath::pi() / 2 )
return HNumber( 1 );
else if( x == HMath::pi() * 3 / 2 )
return HNumber( -1 );
// Taylor expansion: sin(x) = x - x^3/3! + x^5/5! - x^7/7! ...
HNumber xsq = xs*xs;
HNumber num = xs;
HNumber den = 1;
HNumber sum = xs;
// loop for the series (limited to avoid nasty cases)
for( int i = 3; i < HMATH_MAX_PREC; i+=2 )
{
num *= xsq;
if( num.isZero() ) break;
den *= HNumber(i-1);
den *= HNumber(i);
den = HMath::negate( den );
HNumber s = HMath::div( num, den );
if( s.isZero() ) break;
sum += s;
}
return sum;
}
HNumber HMath::cos( const HNumber& x )
{
if( x.isNan() )
return HNumber::nan();
// adjust to small angle for speedup
HNumber xs = simplifyAngle( x );
// limits shortcut
if ( x == 0 || x == HMath::pi() * 2 )
return HNumber( 1 );
else if( x == HMath::pi() / 2 || x == HMath::pi() * 3 / 2 )
return HNumber( 0 );
else if( x == HMath::pi() )
return HNumber( -1 );
// Taylor expansion: cos(x) = 1 - x^2/2! + x^4/4! - x^6/6! ...
HNumber xsq = xs*xs;
HNumber num = 1;
HNumber den = 1;
HNumber sum = 1;
// loop for the series (limited to avoid nasty cases)
for( int i = 2; i < HMATH_MAX_PREC; i+=2 )
{
num *= xsq;
if( num.isZero() ) break;
den *= HNumber(i-1);
den *= HNumber(i);
den = HMath::negate( den );
HNumber s = num / den;
if( s.isZero() ) break;
sum += s;
}
return sum;
}
HNumber HMath::tan( const HNumber& x )
{
return HMath::sin(x) / HMath::cos(x);
}
HNumber HMath::cot( const HNumber& x )
{
return HMath::cos(x) / HMath::sin(x);
}
HNumber HMath::sec( const HNumber& x )
{
return HNumber(1) / HMath::cos(x);
}
HNumber HMath::csc( const HNumber& x )
{
return HNumber(1) / HMath::sin(x);
}
HNumber HMath::atan( const HNumber& x )
{
if( x.isNan() )
return HNumber::nan();
// useful constants
HNumber one("1.0");
HNumber c( "0.2" );
// short circuit
if( x == c )
return HNumber("0.19739555984988075837004976519479029344758510378785"
"21015176889402410339699782437857326978280372880441"
"12628118073691360104456479886794239355747565495216"
"30327005221074700156450155600612861855266332573187" );
if( x == one )
// essentially equals to HMath::pi()/4;
return HNumber("0.78539816339744830961566084581987572104929234984377"
"64552437361480769541015715522496570087063355292669"
"95537021628320576661773461152387645557931339852032"
"12027936257102567548463027638991115573723873259549" );
bool negative = x.isNegative();
HNumber xs = HMath::abs( x );
// adjust so that x is less than c (we choose c = 0.2)
// use the fact that atan(x) = atan(c) + atan((x-c)/(1+xc))
HNumber factor(0);
HNumber base(0);
while( xs > c )
{
base = HMath::atan( c );
factor += one;
HNumber p = xs - c;
HNumber q = xs * c;
xs = p / (q+one);
}
// Taylor series: atan(x) = x - x^3/3 + x^5/5 - x^7/7 + ...
HNumber num = xs;
HNumber xsq = xs*xs;
HNumber den = 1;
HNumber sum = xs;
// loop for the series (limited to avoid nasty cases)
for( int i = 3; i < HMATH_MAX_PREC; i+=2 )
{
num *= xsq;
if( num.isZero() ) break;
den = HNumber(i);
int n = (i-1)/2;
if( n&1 ) den = HNumber(-i);
HNumber s = HMath::div( num, den );
if( s.isZero() ) break;
sum += s;
}
HNumber result = factor*base + sum;
if( negative ) result = HMath::negate( result );
return result;
};
HNumber HMath::asin( const HNumber & x )
{
if ( x.isNan() || x < -1 || x > 1 )
return HNumber::nan();
// shortcuts
if ( x == -1 )
return HMath::pi() / 2 * (-1);
if ( x == 0 )
return HNumber( 0 );
if ( x == 1 )
return HMath::pi() / 2;
// asin( x ) = atan( x / sqrt( 1 - x * x ) );
HNumber d = HMath::sqrt( HNumber( 1 ) - x * x );
if ( d == 0 )
{
HNumber result = HMath::pi() / 2;
if ( x < 0 )
result *= -1;
return result;
}
return HMath::atan( x / d );
};
HNumber HMath::acos( const HNumber & x )
{
if ( x.isNan() || x < -1 || x > 1 )
return HNumber::nan();
// shortcuts
if ( x == -1 )
return HMath::pi();
if ( x == 0 )
return HMath::pi()/2;
if ( x == 1 )
return 0;
// acos( x ) = atan( sqrt( 1 - x * x ) / x );
HNumber n = HMath::sqrt( HNumber( 1 ) - x * x );
return HMath::atan( n / x );
};
HNumber HMath::sinh( const HNumber& x )
{
if( x.isNan() )
return HNumber::nan();
// sinh(x) = 0.5*(e^x - e^(-x) )
HNumber result = HMath::exp(x) - HMath::exp( HMath::negate(x) );
result = result / 2;
return result;
}
HNumber HMath::cosh( const HNumber& x )
{
if( x.isNan() )
return HNumber::nan();
// cosh(x) = 0.5*(e^x - e^(-x) )
HNumber result = HMath::exp(x) + HMath::exp( HMath::negate(x) );
result = result / 2;
return result;
}
HNumber HMath::tanh( const HNumber& x )
{
if( x.isNan() )
return HNumber::nan();
// tanh(h) = sinh(x)/cosh(x)
HNumber c = HMath::cosh( x );
if( c.isZero() )
return HNumber::nan();
HNumber s = HMath::sinh( x );
HNumber result = s / c;
return result;
}
HNumber HMath::sign( const HNumber& x )
{
if( x.isNan() )
return HNumber::nan();
HNumber result( 0 );
if (x == result)
return result;
if (x < result)
result = HNumber(-1);
else
result = HNumber(1);
return result;
}
HNumber HMath::nCr( const HNumber & n,
const HNumber & r )
{
if ( n.isNan() || n < 0 ||
r.isNan() || r < 0 ||
r > n )
return HNumber::nan();
// shortcuts
HNumber one = HNumber( 1 );
if ( r == HNumber( 0 ) || r == n )
return one;
if ( r == one )
return n;
if ( r > n/2 )
return factorial( n, r+1 ) / factorial( n-r, 1 );
else
return factorial( n, n-r+1 ) / factorial( r, 1 );
}
HNumber HMath::nPr( const HNumber & n,
const HNumber & r )
{
if ( n.isNan() || n < 0 ||
r.isNan() || r < 0 ||
r > n )
return HNumber::nan();
// shortcuts
HNumber one = HNumber( 1 );
if ( r == HNumber( 0 ) )
return one;
if ( r == one )
return n;
if ( r == n )
return factorial( n );
return factorial( n, n-r+1 );
}
HNumber HMath::factorial( const HNumber& x, const HNumber& base )
{
if( x.isNan()
|| x < HNumber(0) || !x.isInteger()
|| base < HNumber(1) || !base.isInteger()
|| (x < base && x != HNumber(0)) )
return HNumber::nan();
if( x == HNumber(0) || x == HNumber(1) )
return HNumber(1);
if( x == base )
return x;
HNumber one(1);
HNumber result = one;
HNumber n = base - one;
do
{
n = n + one;
result = result * n;
}
while (n < x);
return result;
}
HNumber HMath::binomialPmf( const HNumber & k,
const HNumber & n,
const HNumber & p )
{
if ( k.isNan() || ! k.isInteger() || k < 0 || k > n
|| n.isNan() || ! n.isInteger() || n < 0
|| p.isNan() || p < 0 || p > 1 )
return HNumber::nan();
return HMath::nCr( n, k ) * HMath::raise( p, k ) *
HMath::raise( HNumber(1)-p, n-k );
}
HNumber HMath::binomialCdf( const HNumber & k,
const HNumber & n,
const HNumber & p )
{
if ( k.isNan() || ! k.isInteger() || k < 0 || k > n
|| n.isNan() || ! n.isInteger() || n < 0
|| p.isNan() || p < 0 || p > 1 )
return HNumber::nan();
HNumber result( 0 );
for ( HNumber i( 0 ); i <= k; i += 1 )
result += HMath::nCr( n, i ) * HMath::raise( p, i )
* HMath::raise( HNumber(1)-p, n-i );
return result;
}
HNumber HMath::binomialMean( const HNumber & n,
const HNumber & p )
{
if ( n.isNan() || ! n.isInteger() || n < 0
|| p.isNan() || p < 0 || p > 1 )
return HNumber::nan();
return n * p;
}
HNumber HMath::binomialVariance( const HNumber & n,
const HNumber & p )
{
if ( n.isNan() || ! n.isInteger() || n < 0
|| p.isNan() || p < 0 || p > 1 )
return HNumber::nan();
return n * p * ( HNumber(1) - p );
}
HNumber HMath::hypergeometricPmf( const HNumber & k,
const HNumber & N,
const HNumber & M,
const HNumber & n )
{
if ( k.isNan() || ! k.isInteger() || k < max( 0, M+n-N ) || k > min( M, n )
|| N.isNan() || ! N.isInteger() || N < 0
|| M.isNan() || ! M.isInteger() || M < 0 || M > N
|| n.isNan() || ! n.isInteger() || n < 0 || n > N )
return HNumber::nan();
return HMath::nCr( M, k ) * HMath::nCr( N-M, n-k ) / HMath::nCr( N, n );
}
HNumber HMath::hypergeometricCdf( const HNumber & k,
const HNumber & N,
const HNumber & M,
const HNumber & n )
{
if ( k.isNan() || ! k.isInteger() || k < max( 0, M+n-N ) || k > min( M, n )
|| N.isNan() || ! N.isInteger() || N < 0
|| M.isNan() || ! M.isInteger() || M < 0 || M > N
|| n.isNan() || ! n.isInteger() || n < 0 || n > N )
return HNumber::nan();
HNumber result( 0 );
for ( HNumber i( 0 ); i <= k; i += 1 )
result += HMath::nCr( M, i ) * HMath::nCr( N-M, n-i ) / HMath::nCr( N, n );
return result;
}
HNumber HMath::hypergeometricMean( const HNumber & N,
const HNumber & M,
const HNumber & n )
{
if ( N.isNan() || ! N.isInteger() || N < 0
|| M.isNan() || ! M.isInteger() || M < 0 || M > N
|| n.isNan() || ! n.isInteger() || n < 0 || n > N )
return HNumber::nan();
return n * M / N;
}
HNumber HMath::hypergeometricVariance( const HNumber & N,
const HNumber & M,
const HNumber & n )
{
if ( N.isNan() || ! N.isInteger() || N < 0
|| M.isNan() || ! M.isInteger() || M < 0 || M > N
|| n.isNan() || ! n.isInteger() || n < 0 || n > N )
return HNumber::nan();
return (n * (M/N) * (HNumber(1) - M/N) * (N-n)) / (N - HNumber(1));
}
HNumber HMath::poissonPmf( const HNumber & k,
const HNumber & l )
{
if ( k.isNan() || ! k.isInteger() || k < 0
|| l.isNan() || l < 0 )
return HNumber::nan();
return exp( l*(-1) ) * raise( l, k ) / factorial( k );
}
HNumber HMath::poissonCdf( const HNumber & k,
const HNumber & l )
{
if ( k.isNan() || ! k.isInteger() || k < 0
|| l.isNan() || l < 0 )
return HNumber::nan();
HNumber result( 0 );
for ( HNumber i( 0 ); i <= k; i += 1 )
result += exp( l*(-1) ) * raise( l, i ) / factorial( i );
return result;
}
HNumber HMath::poissonMean( const HNumber & l )
{
if ( l.isNan() || l < 0 )
return HNumber::nan();
return l;
}
HNumber HMath::poissonVariance( const HNumber & l )
{
if ( l.isNan() || l < 0 )
return HNumber::nan();
return l;
}
void HMath::finalize()
{
bc_free_num( &_zero_ );
bc_free_num( &_one_ );
bc_free_num( &_two_ );
free( _one_ );
free( _zero_ );
free( _two_ );
h_grabfree();
h_grabfree();
h_grabfree();
h_grabfree();
}
std::ostream& operator<<( std::ostream& s, const HNumber& n )
{
char* str = HMath::formatFixed( n );
s << str;
delete[] str;
return s;
}