now creating a linkable library

1 files changed, 36 insertions, 0 deletions

diff --git a/vowpalwabbit/loss_functions.h b/vowpalwabbit/loss_functions.h
new file mode 100644
index 00000000..59ebeae4
--- /dev/null
+++ b/vowpalwabbit/loss_functions.h
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+/*
+Copyright (c) 2009 Yahoo! Inc.  All rights reserved.  The copyrights
+embodied in the content of this file are licensed under the BSD
+(revised) open source license
+ */
+
+#ifndef LOSSFUNCTIONS_H_
+#define LOSSFUNCTIONS_H_
+
+#include <string>
+
+class loss_function {
+
+public :
+	/*
+	 * getLoss evaluates the example loss.
+	 * The function returns the loss value
+	 */
+	//virtual float getLoss(example *&ec, gd_vars &vars) = 0;
+	virtual float getLoss(float prediction, float label) = 0;
+
+	/*
+	 * getUpdate evaluates the update scalar
+	 * The function return the update scalar
+	 */
+	virtual float getUpdate(float prediction, float label, float eta_t, float norm) = 0;
+	virtual float getRevertingWeight(float prediction, float eta_t) = 0;
+	virtual float getSquareGrad(float prediction, float label) = 0;
+	virtual float first_derivative(float prediction, float label) = 0;
+	virtual float second_derivative(float prediction, float label) = 0;
+	virtual ~loss_function() {};
+};
+
+loss_function* getLossFunction(std::string funcName, double loss_parameter = 0);
+
+#endif /* LOSSFUNCTIONS_H_ */