From b4b729a15e577c68f64e0ac69fb299de6f5f706c Mon Sep 17 00:00:00 2001
From: Joseph Redmon <pjreddie@gmail.com>
Date: Thu, 17 Apr 2014 16:58:24 +0000
Subject: [PATCH] Merge branch 'master' of pjreddie.com:jnet

---
 src/softmax_layer.c |   40 ++++++++++++++++++++++++++++++++--------
 1 files changed, 32 insertions(+), 8 deletions(-)

diff --git a/src/softmax_layer.c b/src/softmax_layer.c
index 28696b7..1268423 100644
--- a/src/softmax_layer.c
+++ b/src/softmax_layer.c
@@ -3,20 +3,22 @@
 #include <stdlib.h>
 #include <stdio.h>
 
-softmax_layer *make_softmax_layer(int inputs)
+softmax_layer *make_softmax_layer(int batch, int inputs)
 {
-    printf("Softmax Layer: %d inputs\n", inputs);
+    fprintf(stderr, "Softmax Layer: %d inputs\n", inputs);
     softmax_layer *layer = calloc(1, sizeof(softmax_layer));
+    layer->batch = batch;
     layer->inputs = inputs;
-    layer->output = calloc(inputs, sizeof(double));
-    layer->delta = calloc(inputs, sizeof(double));
+    layer->output = calloc(inputs*batch, sizeof(float));
+    layer->delta = calloc(inputs*batch, sizeof(float));
     return layer;
 }
 
-void forward_softmax_layer(const softmax_layer layer, double *input)
+/* UNSTABLE!
+void forward_softmax_layer(const softmax_layer layer, float *input)
 {
     int i;
-    double sum = 0;
+    float sum = 0;
     for(i = 0; i < layer.inputs; ++i){
         sum += exp(input[i]);
     }
@@ -24,11 +26,33 @@
         layer.output[i] = exp(input[i])/sum;
     }
 }
+*/
+void forward_softmax_layer(const softmax_layer layer, float *input)
+{
+    int i,b;
+    for(b = 0; b < layer.batch; ++b){
+        float sum = 0;
+        float largest = 0;
+        for(i = 0; i < layer.inputs; ++i){
+            if(input[i+b*layer.inputs] > largest) largest = input[i+b*layer.inputs];
+        }
+        for(i = 0; i < layer.inputs; ++i){
+            sum += exp(input[i+b*layer.inputs]-largest);
+            //printf("%f, ", input[i]);
+        }
+        //printf("\n");
+        if(sum) sum = largest+log(sum);
+        else sum = largest-100;
+        for(i = 0; i < layer.inputs; ++i){
+            layer.output[i+b*layer.inputs] = exp(input[i+b*layer.inputs]-sum);
+        }
+    }
+}
 
-void backward_softmax_layer(const softmax_layer layer, double *input, double *delta)
+void backward_softmax_layer(const softmax_layer layer, float *input, float *delta)
 {
     int i;
-    for(i = 0; i < layer.inputs; ++i){
+    for(i = 0; i < layer.inputs*layer.batch; ++i){
         delta[i] = layer.delta[i];
     }
 }

--
Gitblit v1.10.0