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Diffstat (limited to 'mgizapp/src/logprob.h')
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1 files changed, 0 insertions, 217 deletions
diff --git a/mgizapp/src/logprob.h b/mgizapp/src/logprob.h deleted file mode 100644 index 14696ac..0000000 --- a/mgizapp/src/logprob.h +++ /dev/null @@ -1,217 +0,0 @@ -/* - -EGYPT Toolkit for Statistical Machine Translation -Written by Yaser Al-Onaizan, Jan Curin, Michael Jahr, Kevin Knight, John Lafferty, Dan Melamed, David Purdy, Franz Och, Noah Smith, and David Yarowsky. - -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; if not, write to the Free Software -Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, -USA. - -*/ -#ifndef _LOGPROB_H -#define _LOGPROB_H - -// Routines to perform integer exponential arithmetic. -// A number x is represented as n, where x = b**n -// It is assumed that b > 1, something like b = 1.001 - -#include <iostream> -#include <math.h> -#include <algorithm> - -//#define MAX(A,B) ((A) > (B) ? (A) : (B)) -//#define MIN(A,B) ((A) > (B) ? (B) : (A)) - - -class LogProb { -public: - // mj for cross entropy - double base2() const { - return (logr * logb2 / log(2)); - } - - // Constructors - LogProb() : logr(zeron) {} - LogProb(const LogProb &obj) : logr(obj.logr) {} - LogProb(double x) : logr(x == 0.0 ? zeron : round(log(x)/logb2)) {} - // destructor - ~LogProb() {} // default destructor - - operator double() const // converts logr to (double) b**logr - { - if (logr < nmin) return ntof[0]; - if (logr > nmax) return ntof[nmax-nmin]; - return ntof[logr-nmin]; - } - - LogProb &operator=(const LogProb &obj) { logr = obj.logr; return *this; } - int operator!() const { return logr == zeron; } - - // iostream friend specifications - friend std::ostream& operator<<(std::ostream& os, const LogProb &obj); - friend std::istream& operator>>(std::istream& is, LogProb &obj); - friend std::ostream& operator<<=(std::ostream& os, const LogProb &obj); - friend std::istream& operator>>=(std::istream& is, LogProb &obj); - - // arithmetic operators - LogProb &operator+=(const LogProb &add) // logr2 = logb ( b**logr2 + b**logr1 ) - // Add two numbers represented as logarithms. Use the following method: - // b**n + b**m = b**n(1 + b**(m-n)), assuming n >= m. - { - if (add.logr == zeron) - return *this; - if (logr == zeron) - { - logr = add.logr; - return *this; - } - int a = add.logr - logr; - if (a > 0) - { - a = -a; - logr = add.logr; - } - if (a < tblbnd) - return *this; - logr += addtbl[a-tblbnd]; - return *this; - } - - LogProb &operator-=(const LogProb &); // logr2 = logb ( b**logr2 + b**logr1 ) - LogProb operator*(const LogProb &mul) const // logr3 = logr2 + logr1 - { - LogProb result; // start out with result == 0 - if ((logr != zeron) && (mul.logr != zeron)) - result.logr = std::max(logr+mul.logr, zeron); - return result; - } - LogProb operator*(double x) const // logr3 = logr2 + logr1 - { - return (*this)*(LogProb)x; - } - LogProb operator^(const int i) const // logr2 = logr1 * i - { - LogProb result; // start out with result == 0 - // if ((logr != zeron) && (mul.logr != zeron)) - result.logr = logr * i ; - return result; - } - LogProb &operator*=(const LogProb &mul) // logr2 += logr1 - { - if ((logr == zeron) || (mul.logr == zeron)) - logr = zeron; - else - logr = std::max(logr+mul.logr, zeron); - return *this; - } - LogProb operator/(const LogProb &div) const // logr3 = logr2 -logr1 - { - LogProb result; - if (logr != zeron) - result.logr = std::max(logr - div.logr, zeron); - return result; - } - LogProb &operator/=(const LogProb &div) // logr2 -= logr1 - { - if (logr != zeron) - logr = std::max(logr - div.logr, zeron); - return *this; - } - LogProb operator+(const LogProb &l) const // logr3 = logb ( b**logr2 + b**logr1 ) - { LogProb result(*this); result += l; return result; } - LogProb operator-(const LogProb &l) const // logr3 = logb ( b**logr2 - b**logr1 ) - { LogProb result(*this); result -= l; return result; } - LogProb power(const int n) const // logr2 = logr1 * int - { LogProb result(*this); result.logr *= n; return result; } - - // Conditional operators - int operator<(const LogProb &obj) const { return logr < obj.logr; } - int operator<=(const LogProb &obj) const { return logr <= obj.logr; } - int operator>(const LogProb &obj) const { return logr > obj.logr; } - int operator>=(const LogProb &obj) const { return logr >= obj.logr; } - int operator==(const LogProb &obj) const { return logr == obj.logr; } - int operator!=(const LogProb &obj) const { return logr != obj.logr; } - int operator<(double d) const { return ((double)*this) < d; } - int operator<=(double d) const { return ((double)*this) <= d; } - int operator>(double d) const { return ((double)*this) > d; } - int operator>=(double d) const { return ((double)*this) >= d; } - int operator==(double d) const { return ((double)*this) == d; } - int operator!=(double d) const { return ((double)*this) != d; } - - - LogProb &SetZero() { logr = zeron; return *this; } // representation of 0, - LogProb &SetOne() { logr = onen; return *this; } // 1, and - LogProb &SetInf() { logr = infn; return *this; } // inf in logarithm domain - -private: - int logr; // a representation of logarithm - // static constants - static const int initialized; // initialization flag - static const double b; - static const double logb2; - static const int nmin, nmax; - static const int tblbnd; - static const int zeron, onen, infn; // zero, one, and inf in log domain - static const int max_2byte_integer, min_2byte_integer; - - // Arithmetic computation Tables - static double *ntof; - static int *addtbl; - static int *subtbl; - - static int Initialize(); - -public: - static void FreeTables(); - // constants for initializing LogProbs to 0 or 1 - static const LogProb zero; - static const LogProb one; - static const LogProb minus2; - static const LogProb minus4; - static const LogProb minus6; - static const LogProb minus8; - static const LogProb minus10; - static const LogProb minus12; - static const LogProb minus14; - static const LogProb minus16; -}; - -// iostream friend operators -inline std::ostream &operator<<(std::ostream& os, const LogProb &obj) -{ - return os << (double) obj; // output in linear domain, b**logr -} - -inline std::istream &operator>>(std::istream& is, LogProb &obj) -{ - double d; - is >> d; - obj = d; - return is; -} - -inline std::ostream &operator<<=(std::ostream& os, const LogProb &obj) // write binary -{ - os.write((const char *)&obj.logr, sizeof(obj.logr)); - return os; -} - -inline std::istream &operator>>=(std::istream& is, LogProb &obj) -{ - is.read((char *)&obj.logr, sizeof(obj.logr)); - return is; -} - -#endif - |