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authorChris Dyer <redpony@gmail.com>2009-12-14 20:35:11 -0500
committerChris Dyer <redpony@gmail.com>2009-12-14 20:35:11 -0500
commit851e389dffdd6996ea32d70defb8906de80b9edc (patch)
tree8c68ee77205badc056b8ab5b332e67e3e98017df /decoder/logval.h
parentdc6930c00b4b276883280cff1ed6dcd9ddef03c7 (diff)
few small fixes of alignment tools, add new orthographic similarity feature for word aligner, final naming of directories, libraries in cdec
Diffstat (limited to 'decoder/logval.h')
-rw-r--r--decoder/logval.h136
1 files changed, 136 insertions, 0 deletions
diff --git a/decoder/logval.h b/decoder/logval.h
new file mode 100644
index 00000000..a8ca620c
--- /dev/null
+++ b/decoder/logval.h
@@ -0,0 +1,136 @@
+#ifndef LOGVAL_H_
+#define LOGVAL_H_
+
+#include <cmath>
+#include <limits>
+
+template <typename T>
+class LogVal {
+ public:
+ LogVal() : v_(-std::numeric_limits<T>::infinity()) {}
+ explicit LogVal(double x) : v_(std::log(x)) {}
+ LogVal<T>(const LogVal<T>& o) : v_(o.v_) {}
+ static LogVal<T> One() { return LogVal(1); }
+ static LogVal<T> Zero() { return LogVal(); }
+
+ void logeq(const T& v) { v_ = v; }
+
+ LogVal& operator+=(const LogVal& a) {
+ if (a.v_ == -std::numeric_limits<T>::infinity()) return *this;
+ if (a.v_ < v_) {
+ v_ = v_ + log1p(std::exp(a.v_ - v_));
+ } else {
+ v_ = a.v_ + log1p(std::exp(v_ - a.v_));
+ }
+ return *this;
+ }
+
+ LogVal& operator*=(const LogVal& a) {
+ v_ += a.v_;
+ return *this;
+ }
+
+ LogVal& operator*=(const T& a) {
+ v_ += log(a);
+ return *this;
+ }
+
+ LogVal& operator/=(const LogVal& a) {
+ v_ -= a.v_;
+ return *this;
+ }
+
+ LogVal& poweq(const T& power) {
+ if (power == 0) v_ = 0; else v_ *= power;
+ return *this;
+ }
+
+ LogVal pow(const T& power) const {
+ LogVal res = *this;
+ res.poweq(power);
+ return res;
+ }
+
+ operator T() const {
+ return std::exp(v_);
+ }
+
+ T v_;
+};
+
+template<typename T>
+LogVal<T> operator+(const LogVal<T>& o1, const LogVal<T>& o2) {
+ LogVal<T> res(o1);
+ res += o2;
+ return res;
+}
+
+template<typename T>
+LogVal<T> operator*(const LogVal<T>& o1, const LogVal<T>& o2) {
+ LogVal<T> res(o1);
+ res *= o2;
+ return res;
+}
+
+template<typename T>
+LogVal<T> operator*(const LogVal<T>& o1, const T& o2) {
+ LogVal<T> res(o1);
+ res *= o2;
+ return res;
+}
+
+template<typename T>
+LogVal<T> operator*(const T& o1, const LogVal<T>& o2) {
+ LogVal<T> res(o2);
+ res *= o1;
+ return res;
+}
+
+template<typename T>
+LogVal<T> operator/(const LogVal<T>& o1, const LogVal<T>& o2) {
+ LogVal<T> res(o1);
+ res /= o2;
+ return res;
+}
+
+template<typename T>
+T log(const LogVal<T>& o) {
+ return o.v_;
+}
+
+template <typename T>
+LogVal<T> pow(const LogVal<T>& b, const T& e) {
+ return b.pow(e);
+}
+
+template <typename T>
+bool operator<(const LogVal<T>& lhs, const LogVal<T>& rhs) {
+ return (lhs.v_ < rhs.v_);
+}
+
+template <typename T>
+bool operator<=(const LogVal<T>& lhs, const LogVal<T>& rhs) {
+ return (lhs.v_ <= rhs.v_);
+}
+
+template <typename T>
+bool operator>(const LogVal<T>& lhs, const LogVal<T>& rhs) {
+ return (lhs.v_ > rhs.v_);
+}
+
+template <typename T>
+bool operator>=(const LogVal<T>& lhs, const LogVal<T>& rhs) {
+ return (lhs.v_ >= rhs.v_);
+}
+
+template <typename T>
+bool operator==(const LogVal<T>& lhs, const LogVal<T>& rhs) {
+ return (lhs.v_ == rhs.v_);
+}
+
+template <typename T>
+bool operator!=(const LogVal<T>& lhs, const LogVal<T>& rhs) {
+ return (lhs.v_ != rhs.v_);
+}
+
+#endif