From cae538d7a50d36a884d0f0361d1ee14c73e2429d Mon Sep 17 00:00:00 2001
From: lisyarus <lisyarus@gmail.com>
Date: Thu, 30 Dec 2021 17:21:10 +0300
Subject: [PATCH] Add geom::matrix::diagonal

---
 libs/geom/include/psemek/geom/matrix.hpp | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/libs/geom/include/psemek/geom/matrix.hpp b/libs/geom/include/psemek/geom/matrix.hpp
index 55dad440..a30e2cb5 100644
--- a/libs/geom/include/psemek/geom/matrix.hpp
+++ b/libs/geom/include/psemek/geom/matrix.hpp
@@ -48,6 +48,7 @@ namespace psemek::geom
 		static matrix zero();
 		static matrix identity();
 		static matrix scalar(T const & s);
+		static matrix diagonal(vector<T, std::min(R, C)> const & d);
 	};
 
 	template <typename T, std::size_t R, std::size_t C>
@@ -74,6 +75,15 @@ namespace psemek::geom
 		return m;
 	}
 
+	template <typename T, std::size_t R, std::size_t C>
+	matrix<T, R, C> matrix<T, R, C>::diagonal(vector<T, std::min(R, C)> const & d)
+	{
+		matrix<T, R, C> m = zero();
+		for (std::size_t i = 0; i < std::min(R, C); ++i)
+			m[i][i] = d[i];
+		return m;
+	}
+
 	template <typename T, std::size_t R, std::size_t C>
 	bool operator == (matrix<T, R, C> const & m1, matrix<T, R, C> const & m2)
 	{