From e7688a05a194e3c8baf3c11fbf09b7f5e8640a77 Mon Sep 17 00:00:00 2001
From: Joseph Redmon <pjreddie@gmail.com>
Date: Wed, 06 May 2015 21:08:16 +0000
Subject: [PATCH] no idea

---
 src/dropout_layer.c |   43 ++++++++++++++++++++++++++++++++++++-------
 1 files changed, 36 insertions(+), 7 deletions(-)

diff --git a/src/dropout_layer.c b/src/dropout_layer.c
index fcad7b9..7fbf8ff 100644
--- a/src/dropout_layer.c
+++ b/src/dropout_layer.c
@@ -1,6 +1,9 @@
 #include "dropout_layer.h"
-#include "stdlib.h"
-#include "stdio.h"
+#include "params.h"
+#include "utils.h"
+#include "cuda.h"
+#include <stdlib.h>
+#include <stdio.h>
 
 dropout_layer *make_dropout_layer(int batch, int inputs, float probability)
 {
@@ -9,18 +12,44 @@
     layer->probability = probability;
     layer->inputs = inputs;
     layer->batch = batch;
+    layer->rand = calloc(inputs*batch, sizeof(float));
+    layer->scale = 1./(1.-probability);
+    #ifdef GPU
+    layer->rand_gpu = cuda_make_array(layer->rand, inputs*batch);
+    #endif
     return layer;
 } 
 
-void forward_dropout_layer(dropout_layer layer, float *input)
+void resize_dropout_layer(dropout_layer *layer, int inputs)
+{
+    layer->rand = realloc(layer->rand, layer->inputs*layer->batch*sizeof(float));
+    #ifdef GPU
+    cuda_free(layer->rand_gpu);
+
+    layer->rand_gpu = cuda_make_array(layer->rand, inputs*layer->batch);
+    #endif
+}
+
+void forward_dropout_layer(dropout_layer layer, network_state state)
 {
     int i;
+    if (!state.train) return;
     for(i = 0; i < layer.batch * layer.inputs; ++i){
-        if((float)rand()/RAND_MAX < layer.probability) input[i] = 0;
-        else input[i] /= (1-layer.probability);
+        float r = rand_uniform();
+        layer.rand[i] = r;
+        if(r < layer.probability) state.input[i] = 0;
+        else state.input[i] *= layer.scale;
     }
 }
-void backward_dropout_layer(dropout_layer layer, float *input, float *delta)
+
+void backward_dropout_layer(dropout_layer layer, network_state state)
 {
-    // Don't do shit LULZ
+    int i;
+    if(!state.delta) return;
+    for(i = 0; i < layer.batch * layer.inputs; ++i){
+        float r = layer.rand[i];
+        if(r < layer.probability) state.delta[i] = 0;
+        else state.delta[i] *= layer.scale;
+    }
 }
+

--
Gitblit v1.10.0