From b77060abac695c36156eea650efb04dff2c98396 Mon Sep 17 00:00:00 2001
From: lisyarus <lisyarus@gmail.com>
Date: Fri, 17 Jun 2022 18:51:39 +0300
Subject: [PATCH] Support retrieving geom::matrix row or column as a vector

---
 libs/geom/include/psemek/geom/matrix.hpp | 18 ++++++++++++++++++
 1 file changed, 18 insertions(+)

diff --git a/libs/geom/include/psemek/geom/matrix.hpp b/libs/geom/include/psemek/geom/matrix.hpp
index a30e2cb5..2f5ff777 100644
--- a/libs/geom/include/psemek/geom/matrix.hpp
+++ b/libs/geom/include/psemek/geom/matrix.hpp
@@ -288,6 +288,24 @@ namespace psemek::geom
 		return result;
 	}
 
+	template <typename T, std::size_t R, std::size_t C>
+	vector<T, C> row(matrix<T, R, C> const & m, std::size_t i)
+	{
+		vector<T, C> r;
+		for (std::size_t j = 0; j < C; ++j)
+			r[j] = m[i][j];
+		return r;
+	}
+
+	template <typename T, std::size_t R, std::size_t C>
+	vector<T, R> column(matrix<T, R, C> const & m, std::size_t j)
+	{
+		vector<T, R> r;
+		for (std::size_t i = 0; i < R; ++i)
+			r[i] = m[i][j];
+		return r;
+	}
+
 	template <typename T, std::size_t R, std::size_t C>
 	T frobenius_norm_sqr(matrix<T, R, C> const & m)
 	{