From 16b27f9c7c6ab4d02f7d90ef2632229c305f7cc0 Mon Sep 17 00:00:00 2001
From: "szewczyk.franciszek02" <szewczyk.franciszek02@gmail.com>
Date: Wed, 8 Nov 2023 17:58:01 +0100
Subject: [PATCH 1/4] Constant Iterator of vector

---
 include/core/Vector.hpp       | 39 +++++++++++++++++++++++++++++++++++
 include/nn/layers/Dropout.hpp |  4 ++--
 2 files changed, 41 insertions(+), 2 deletions(-)

diff --git a/include/core/Vector.hpp b/include/core/Vector.hpp
index b13783a..fdaa4e2 100644
--- a/include/core/Vector.hpp
+++ b/include/core/Vector.hpp
@@ -15,6 +15,7 @@
 namespace shkyera {
 
 template <typename T> class Vector;
+
 using Vec32 = Vector<Type::float32>;
 using Vec64 = Vector<Type::float64>;
 
@@ -43,6 +44,21 @@ template <typename T> class Vector {
     Vector<T> &operator*=(ValuePtr<T> val);
 
     ValuePtr<T> operator[](size_t index) const;
+
+    class ConstIterator {
+      private:
+        size_t _index;
+        const Vector<T> &_vector;
+
+      public:
+        ConstIterator(size_t index, const Vector<T> &vector);
+        const ValuePtr<T> operator*();
+        ConstIterator &operator++();
+        bool operator!=(const ConstIterator &other);
+    };
+
+    ConstIterator begin() const;
+    ConstIterator end() const;
 };
 
 template <typename T> Vector<T>::Vector(std::vector<ValuePtr<T>> values) { _values = values; }
@@ -141,4 +157,27 @@ template <typename T> std::ostream &operator<<(std::ostream &os, const Vector<T>
     return os;
 }
 
+template <typename T> typename Vector<T>::ConstIterator Vector<T>::begin() const { return ConstIterator(0, *this); }
+template <typename T> typename Vector<T>::ConstIterator Vector<T>::end() const { return ConstIterator(size(), *this); }
+
+template <typename T>
+Vector<T>::ConstIterator::ConstIterator(size_t index, const Vector<T> &vector) : _index(index), _vector(vector) {}
+
+template <typename T> const ValuePtr<T> Vector<T>::ConstIterator::operator*() {
+    if (_index < _vector.size()) {
+        return _vector[_index];
+    }
+    throw std::out_of_range("Vector iterator out of range. Tried to access index " + std::to_string(_index) +
+                            " in a Vector of size " + std::to_string(_vector.size()) + ".");
+}
+
+template <typename T> typename Vector<T>::ConstIterator &Vector<T>::ConstIterator::operator++() {
+    ++_index;
+    return *this;
+}
+
+template <typename T> bool Vector<T>::ConstIterator::operator!=(const ConstIterator &other) {
+    return _index != other._index;
+}
+
 } // namespace shkyera
diff --git a/include/nn/layers/Dropout.hpp b/include/nn/layers/Dropout.hpp
index c3a6063..be3966a 100644
--- a/include/nn/layers/Dropout.hpp
+++ b/include/nn/layers/Dropout.hpp
@@ -45,8 +45,8 @@ template <typename T> DropoutPtr<T> Dropout<T>::create(size_t input, size_t size
 template <typename T> Vector<T> Dropout<T>::operator()(const Vector<T> &x) const {
     std::vector<ValuePtr<T>> alteredInput;
     alteredInput.reserve(x.size());
-    for (size_t i = 0; i < x.size(); ++i)
-        alteredInput.push_back(x[i]);
+    for (const ValuePtr<T> &val : x)
+        alteredInput.push_back(val);
 
     std::vector<size_t> indicesToRemove = utils::sample<size_t>(0, x.size() - 1, _dropout * x.size(), false);
     for (size_t idxToRemove : indicesToRemove)

From 006f3f157893545e5bd5cc0a256d84961cd57a7e Mon Sep 17 00:00:00 2001
From: "szewczyk.franciszek02" <szewczyk.franciszek02@gmail.com>
Date: Wed, 8 Nov 2023 18:08:57 +0100
Subject: [PATCH 2/4] Iterating while printing

---
 include/core/Vector.hpp | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/include/core/Vector.hpp b/include/core/Vector.hpp
index fdaa4e2..e730cb9 100644
--- a/include/core/Vector.hpp
+++ b/include/core/Vector.hpp
@@ -150,7 +150,7 @@ template <typename T> ValuePtr<T> Vector<T>::operator[](size_t index) const { re
 template <typename T> std::ostream &operator<<(std::ostream &os, const Vector<T> &vector) {
     os << "Vector(size=" << vector.size() << ", data={";
 
-    for (const ValuePtr<T> val : vector._values)
+    for (auto val : vector)
         os << val << ' ';
 
     os << "})";

From 71bca9be91958b73a671115aac324ad0cf7ca0de Mon Sep 17 00:00:00 2001
From: "szewczyk.franciszek02" <szewczyk.franciszek02@gmail.com>
Date: Wed, 8 Nov 2023 18:31:45 +0100
Subject: [PATCH 3/4] More iterators!

---
 examples/xor_classification.cpp   |  4 ++--
 include/nn/activation/Exp.hpp     |  5 ++---
 include/nn/activation/ReLU.hpp    |  5 ++---
 include/nn/activation/Sigmoid.hpp |  4 ++--
 include/nn/activation/Softmax.hpp | 10 +++++-----
 include/nn/activation/Tanh.hpp    |  5 ++---
 6 files changed, 15 insertions(+), 18 deletions(-)

diff --git a/examples/xor_classification.cpp b/examples/xor_classification.cpp
index d4961c5..e8cd162 100644
--- a/examples/xor_classification.cpp
+++ b/examples/xor_classification.cpp
@@ -16,7 +16,7 @@ int main() {
     auto mlp = SequentialBuilder<Type::float32>::begin()
                 .add(Linear32::create(2, 15))
                 .add(ReLU32::create())
-                .add(Dropout32::create(15, 5, 0.2))
+                .add(Dropout32::create(15, 5, 0.3))
                 .add(Tanh32::create())
                 .add(Linear32::create(5, 2))
                 .add(Softmax32::create())
@@ -27,7 +27,7 @@ int main() {
     Loss::Function32 lossFunction = Loss::CrossEntropy<Type::float32>;
 
     // ------ TRAINING THE NETWORK ------- //
-    for (size_t epoch = 0; epoch < 200; epoch++) {
+    for (size_t epoch = 0; epoch < 500; epoch++) {
         auto epochLoss = Val32::create(0);
 
         optimizer.reset();
diff --git a/include/nn/activation/Exp.hpp b/include/nn/activation/Exp.hpp
index 8ec7a43..15521cf 100644
--- a/include/nn/activation/Exp.hpp
+++ b/include/nn/activation/Exp.hpp
@@ -28,9 +28,8 @@ template <typename T> Vector<T> Exp<T>::operator()(const Vector<T> &x) const {
     std::vector<ValuePtr<T>> out;
     out.reserve(x.size());
 
-    for (size_t i = 0; i < x.size(); ++i) {
-        out.emplace_back(x[i]->exp());
-    }
+    for (auto entry : x)
+        out.emplace_back(entry->exp());
 
     return Vector<T>(out);
 }
diff --git a/include/nn/activation/ReLU.hpp b/include/nn/activation/ReLU.hpp
index b1757c7..dfdce01 100644
--- a/include/nn/activation/ReLU.hpp
+++ b/include/nn/activation/ReLU.hpp
@@ -28,9 +28,8 @@ template <typename T> Vector<T> ReLU<T>::operator()(const Vector<T> &x) const {
     std::vector<ValuePtr<T>> out;
     out.reserve(x.size());
 
-    for (size_t i = 0; i < x.size(); ++i) {
-        out.emplace_back(x[i]->relu());
-    }
+    for (auto entry : x)
+        out.emplace_back(entry->relu());
 
     return Vector<T>(out);
 }
diff --git a/include/nn/activation/Sigmoid.hpp b/include/nn/activation/Sigmoid.hpp
index 8648cfe..6679421 100644
--- a/include/nn/activation/Sigmoid.hpp
+++ b/include/nn/activation/Sigmoid.hpp
@@ -30,8 +30,8 @@ template <typename T> Vector<T> Sigmoid<T>::operator()(const Vector<T> &x) const
     std::vector<ValuePtr<T>> out;
     out.reserve(x.size());
 
-    for (size_t i = 0; i < x.size(); ++i) {
-        out.emplace_back(x[i]->sigmoid());
+    for (auto entry : x) {
+        out.emplace_back(entry->sigmoid());
     }
 
     return Vector<T>(out);
diff --git a/include/nn/activation/Softmax.hpp b/include/nn/activation/Softmax.hpp
index 6f80c09..eb581b7 100644
--- a/include/nn/activation/Softmax.hpp
+++ b/include/nn/activation/Softmax.hpp
@@ -31,13 +31,13 @@ template <typename T> Vector<T> Softmax<T>::operator()(const Vector<T> &x) const
     out.reserve(x.size());
 
     auto maxValue = Value<T>::create(x[0]->getValue());
-    for (size_t i = 1; i < x.size(); ++i)
-        if (x[i] > maxValue)
-            maxValue = x[i];
+    for (auto entry : x)
+        if (entry > maxValue)
+            maxValue = entry;
 
     auto sumExponentiated = Value<T>::create(0);
-    for (size_t i = 0; i < x.size(); ++i) {
-        auto exponentiated = (x[i] - maxValue)->exp();
+    for (auto entry : x) {
+        auto exponentiated = (entry - maxValue)->exp();
         out.emplace_back(exponentiated);
         sumExponentiated = sumExponentiated + exponentiated;
     }
diff --git a/include/nn/activation/Tanh.hpp b/include/nn/activation/Tanh.hpp
index 1bed7ed..ad77677 100644
--- a/include/nn/activation/Tanh.hpp
+++ b/include/nn/activation/Tanh.hpp
@@ -28,9 +28,8 @@ template <typename T> Vector<T> Tanh<T>::operator()(const Vector<T> &x) const {
     std::vector<ValuePtr<T>> out;
     out.reserve(x.size());
 
-    for (size_t i = 0; i < x.size(); ++i) {
-        out.emplace_back(x[i]->tanh());
-    }
+    for (auto entry : x)
+        out.emplace_back(entry->tanh());
 
     return Vector<T>(out);
 }

From e30b15e43b3206b76964d8b78489e561a8b672ce Mon Sep 17 00:00:00 2001
From: "szewczyk.franciszek02" <szewczyk.franciszek02@gmail.com>
Date: Wed, 8 Nov 2023 19:27:33 +0100
Subject: [PATCH 4/4] Iterating with references

---
 examples/xor_classification.cpp   | 4 ++--
 include/nn/Neuron.hpp             | 4 ++--
 include/nn/activation/Exp.hpp     | 2 +-
 include/nn/activation/ReLU.hpp    | 2 +-
 include/nn/activation/Sigmoid.hpp | 2 +-
 include/nn/activation/Softmax.hpp | 4 ++--
 include/nn/activation/Tanh.hpp    | 2 +-
 7 files changed, 10 insertions(+), 10 deletions(-)

diff --git a/examples/xor_classification.cpp b/examples/xor_classification.cpp
index e8cd162..30ff5fa 100644
--- a/examples/xor_classification.cpp
+++ b/examples/xor_classification.cpp
@@ -16,7 +16,7 @@ int main() {
     auto mlp = SequentialBuilder<Type::float32>::begin()
                 .add(Linear32::create(2, 15))
                 .add(ReLU32::create())
-                .add(Dropout32::create(15, 5, 0.3))
+                .add(Dropout32::create(15, 5, 0.2))
                 .add(Tanh32::create())
                 .add(Linear32::create(5, 2))
                 .add(Softmax32::create())
@@ -27,7 +27,7 @@ int main() {
     Loss::Function32 lossFunction = Loss::CrossEntropy<Type::float32>;
 
     // ------ TRAINING THE NETWORK ------- //
-    for (size_t epoch = 0; epoch < 500; epoch++) {
+    for (size_t epoch = 0; epoch < 100; epoch++) {
         auto epochLoss = Val32::create(0);
 
         optimizer.reset();
diff --git a/include/nn/Neuron.hpp b/include/nn/Neuron.hpp
index a4cefa5..6d148de 100644
--- a/include/nn/Neuron.hpp
+++ b/include/nn/Neuron.hpp
@@ -46,8 +46,8 @@ template <typename T> std::vector<ValuePtr<T>> Neuron<T>::parameters() const {
     std::vector<ValuePtr<T>> params;
     params.reserve(_weights.size() + 1);
 
-    for (size_t i = 0; i < _weights.size(); ++i)
-        params.push_back(_weights[i]);
+    for (auto &w : _weights)
+        params.push_back(w);
 
     params.push_back(_bias);
 
diff --git a/include/nn/activation/Exp.hpp b/include/nn/activation/Exp.hpp
index 15521cf..b97bd1d 100644
--- a/include/nn/activation/Exp.hpp
+++ b/include/nn/activation/Exp.hpp
@@ -28,7 +28,7 @@ template <typename T> Vector<T> Exp<T>::operator()(const Vector<T> &x) const {
     std::vector<ValuePtr<T>> out;
     out.reserve(x.size());
 
-    for (auto entry : x)
+    for (auto &entry : x)
         out.emplace_back(entry->exp());
 
     return Vector<T>(out);
diff --git a/include/nn/activation/ReLU.hpp b/include/nn/activation/ReLU.hpp
index dfdce01..7c0f32b 100644
--- a/include/nn/activation/ReLU.hpp
+++ b/include/nn/activation/ReLU.hpp
@@ -28,7 +28,7 @@ template <typename T> Vector<T> ReLU<T>::operator()(const Vector<T> &x) const {
     std::vector<ValuePtr<T>> out;
     out.reserve(x.size());
 
-    for (auto entry : x)
+    for (auto &entry : x)
         out.emplace_back(entry->relu());
 
     return Vector<T>(out);
diff --git a/include/nn/activation/Sigmoid.hpp b/include/nn/activation/Sigmoid.hpp
index 6679421..cbc4ed7 100644
--- a/include/nn/activation/Sigmoid.hpp
+++ b/include/nn/activation/Sigmoid.hpp
@@ -30,7 +30,7 @@ template <typename T> Vector<T> Sigmoid<T>::operator()(const Vector<T> &x) const
     std::vector<ValuePtr<T>> out;
     out.reserve(x.size());
 
-    for (auto entry : x) {
+    for (auto &entry : x) {
         out.emplace_back(entry->sigmoid());
     }
 
diff --git a/include/nn/activation/Softmax.hpp b/include/nn/activation/Softmax.hpp
index eb581b7..004a99c 100644
--- a/include/nn/activation/Softmax.hpp
+++ b/include/nn/activation/Softmax.hpp
@@ -31,12 +31,12 @@ template <typename T> Vector<T> Softmax<T>::operator()(const Vector<T> &x) const
     out.reserve(x.size());
 
     auto maxValue = Value<T>::create(x[0]->getValue());
-    for (auto entry : x)
+    for (auto &entry : x)
         if (entry > maxValue)
             maxValue = entry;
 
     auto sumExponentiated = Value<T>::create(0);
-    for (auto entry : x) {
+    for (auto &entry : x) {
         auto exponentiated = (entry - maxValue)->exp();
         out.emplace_back(exponentiated);
         sumExponentiated = sumExponentiated + exponentiated;
diff --git a/include/nn/activation/Tanh.hpp b/include/nn/activation/Tanh.hpp
index ad77677..5066526 100644
--- a/include/nn/activation/Tanh.hpp
+++ b/include/nn/activation/Tanh.hpp
@@ -28,7 +28,7 @@ template <typename T> Vector<T> Tanh<T>::operator()(const Vector<T> &x) const {
     std::vector<ValuePtr<T>> out;
     out.reserve(x.size());
 
-    for (auto entry : x)
+    for (auto &entry : x)
         out.emplace_back(entry->tanh());
 
     return Vector<T>(out);