From 86d2b8b48abe6c9d586cb226e8f428043cd4efd8 Mon Sep 17 00:00:00 2001
From: Bert Peters <bert@bertptrs.nl>
Date: Thu, 22 Feb 2018 16:20:59 +0100
Subject: [PATCH] Implement some visualisation for ReLU layers.

---
 src/LayerInfo.hpp      |  1 -
 src/visualisations.cpp | 50 +++++++++++++++++++++++++++++++++++++++++-
 2 files changed, 49 insertions(+), 2 deletions(-)

diff --git a/src/LayerInfo.hpp b/src/LayerInfo.hpp
index 9f55886..2261300 100644
--- a/src/LayerInfo.hpp
+++ b/src/LayerInfo.hpp
@@ -16,7 +16,6 @@ namespace fmri
             Convolutional,
             ReLU,
             Pooling,
-            Output,
             InnerProduct,
             DropOut,
             Other
diff --git a/src/visualisations.cpp b/src/visualisations.cpp
index 06201d9..210268e 100644
--- a/src/visualisations.cpp
+++ b/src/visualisations.cpp
@@ -1,5 +1,5 @@
+#include <algorithm>
 #include <numeric>
-#include <utility>
 #include "visualisations.hpp"
 #include "DummyLayerVisualisation.hpp"
 #include "MultiImageVisualisation.hpp"
@@ -41,6 +41,29 @@ static inline int getNodeNormalizer(const LayerData& layer) {
     }
 }
 
+/**
+ * Deduplicate interaction entries.
+ *
+ * For duplicate interactions, the interaction strengths are summed.
+ *
+ * @param entries
+ * @return the deduplicated entries.
+ */
+static EntryList deduplicate(const EntryList& entries)
+{
+    map<pair<size_t, size_t>, float> combiner;
+    for (auto entry : entries) {
+        combiner[entry.second] += entry.first;
+    }
+
+    EntryList result;
+    transform(combiner.begin(), combiner.end(), back_inserter(result), [](const auto& item) {
+        return make_pair(item.second, item.first);
+    });
+
+    return result;
+}
+
 fmri::LayerVisualisation *fmri::getVisualisationForLayer(const fmri::LayerData &layer)
 {
     switch (layer.shape().size()) {
@@ -105,6 +128,29 @@ static Animation *getDropOutAnimation(const fmri::LayerData &prevState,
         }
     }
 
+    results = deduplicate(results);
+
+    return new ActivityAnimation(results, prevPositions.data(), curPositions.data(), -10);
+}
+
+static Animation *getReLUAnimation(const fmri::LayerData &prevState,
+                                   const fmri::LayerData &curState,
+                                   const vector<float> &prevPositions,
+                                   const vector<float> &curPositions) {
+    CHECK_EQ(curState.numEntries(), prevState.numEntries()) << "Layers should be of same size!";
+
+    const auto prevData = prevState.data(), curData = curState.data();
+    const auto sourceNormalize = getNodeNormalizer(prevState);
+    const auto sinkNormalize = getNodeNormalizer(curState);
+
+    EntryList results;
+
+    for (auto i : Range(curState.numEntries())) {
+        results.emplace_back(curData[i] - prevData[i], make_pair(i / sourceNormalize, i / sinkNormalize));
+    }
+
+    results = deduplicate(results);
+
     return new ActivityAnimation(results, prevPositions.data(), curPositions.data(), -10);
 }
 
@@ -126,6 +172,8 @@ Animation * fmri::getActivityAnimation(const fmri::LayerData &prevState, const f
         case LayerInfo::Type::DropOut:
             return getDropOutAnimation(prevState, curState, prevPositions, curPositions);
 
+        case LayerInfo::Type::ReLU:
+            return getReLUAnimation(prevState, curState, prevPositions, curPositions);
 
         default:
             return nullptr;