From d37edd207bf25e3344613206a96f8759f18b1ac2 Mon Sep 17 00:00:00 2001
From: lisyarus <lisyarus@gmail.com>
Date: Thu, 20 Jan 2022 13:52:13 +0300
Subject: [PATCH] Make ml::neural_net return spans

---
 libs/ml/include/psemek/ml/neural_net.hpp           | 12 +++++-------
 libs/ml/include/psemek/ml/neural_net_evaluator.hpp |  6 +++---
 2 files changed, 8 insertions(+), 10 deletions(-)

diff --git a/libs/ml/include/psemek/ml/neural_net.hpp b/libs/ml/include/psemek/ml/neural_net.hpp
index 4582f022..7a673283 100644
--- a/libs/ml/include/psemek/ml/neural_net.hpp
+++ b/libs/ml/include/psemek/ml/neural_net.hpp
@@ -1,6 +1,7 @@
 #pragma once
 
 #include <psemek/ml/activation.hpp>
+#include <psemek/util/span.hpp>
 
 #include <vector>
 #include <stdexcept>
@@ -52,19 +53,16 @@ namespace psemek::ml
 		// A non-empty neural net is basically unusable
 		bool empty() const { return layer_sizes_.empty(); }
 
-		std::size_t layer_count() const { return layer_sizes_.size(); }
-		std::size_t const * layer_sizes() const { return layer_sizes_.data(); }
+		util::span<std::size_t const> layer_sizes() const { return layer_sizes_; }
 
-		std::size_t activation_type_count() const { return activation_types_.size(); }
-		activation_type const * activation_types() const { return activation_types_.data(); }
+		util::span<activation_type const> activation_types() const { return activation_types_; }
 
 		// Weights are stored in a sequential manner, in the order in which they
 		//   appear in evalution of the neural net, i.e. first come the weights
 		//   between layers 0 and 1 (including the bias) in row-major order, then
 		//   1-2 in row-major order, etc.
-		std::size_t weight_count() const { return weights_.size(); }
-		T const * weights() const { return weights_.data(); }
-		T * weights() { return weights_.data(); }
+		util::span<T const> weights() const { return weights_; }
+		util::span<T> weights() { return weights_; }
 
 	private:
 		std::vector<std::size_t> layer_sizes_;
diff --git a/libs/ml/include/psemek/ml/neural_net_evaluator.hpp b/libs/ml/include/psemek/ml/neural_net_evaluator.hpp
index 9f74ecb3..e8ebebab 100644
--- a/libs/ml/include/psemek/ml/neural_net_evaluator.hpp
+++ b/libs/ml/include/psemek/ml/neural_net_evaluator.hpp
@@ -29,13 +29,13 @@ namespace psemek::ml
 	template <typename T>
 	std::vector<T> neural_net_evaluator<T>::evaluate(neural_net<T> const & nn, std::vector<T> input) const
 	{
-		std::size_t const * layer_sizes = nn.layer_sizes();
-		T const * weights = nn.weights();
+		auto layer_sizes = nn.layer_sizes();
+		auto weights = nn.weights().begin();
 
 		if (layer_sizes[0] != input.size())
 			throw wrong_neural_net_input_size{layer_sizes[0], input.size()};
 
-		for (std::size_t l = 0; l + 1 < nn.layer_count(); ++l)
+		for (std::size_t l = 0; l + 1 < layer_sizes.size(); ++l)
 		{
 			temp_.resize(layer_sizes[l + 1]);