From 3e502fb795a93c2f56bf78034c7ff92cc116aeb6 Mon Sep 17 00:00:00 2001
From: Yves Delley <delleyves@gmx.ch>
Date: Mon, 16 Sep 2024 20:34:12 +0200
Subject: [PATCH] increase tolerance for certain math tests to two epsilon

---
 test/runtime/almost_equals.h | 9 +++++----
 test/runtime/math_test.cpp   | 4 ++--
 2 files changed, 7 insertions(+), 6 deletions(-)

diff --git a/test/runtime/almost_equals.h b/test/runtime/almost_equals.h
index 0cc03e8e..4c2153a0 100644
--- a/test/runtime/almost_equals.h
+++ b/test/runtime/almost_equals.h
@@ -35,7 +35,7 @@ namespace mp_units {
 
 template<Quantity T>
 struct AlmostEqualsMatcher : Catch::Matchers::MatcherGenericBase {
-  explicit AlmostEqualsMatcher(const T& target) : target_{target} {}
+  explicit AlmostEqualsMatcher(const T& target, int n_eps) : target_{target}, n_eps_{n_eps} {}
 
   template<std::convertible_to<T> U>
     requires std::same_as<typename T::rep, typename U::rep>
@@ -48,7 +48,7 @@ struct AlmostEqualsMatcher : Catch::Matchers::MatcherGenericBase {
     const auto y = common(other).numerical_value_in(common::unit);
     if constexpr (treat_as_floating_point<rep>) {
       const auto maxXYOne = std::max({rep{1}, abs(x), abs(y)});
-      return abs(x - y) <= std::numeric_limits<rep>::epsilon() * maxXYOne;
+      return abs(x - y) <= (n_eps_ * std::numeric_limits<rep>::epsilon()) * maxXYOne;
     } else {
       if (x >= 0) {
         return x - 1 <= y && y - 1 <= x;
@@ -71,12 +71,13 @@ struct AlmostEqualsMatcher : Catch::Matchers::MatcherGenericBase {
 
 private:
   const T& target_;
+  int n_eps_;
 };
 
 template<Quantity T>
-AlmostEqualsMatcher<T> AlmostEquals(const T& target)
+AlmostEqualsMatcher<T> AlmostEquals(const T& target, int n_eps = 1)
 {
-  return AlmostEqualsMatcher<T>{target};
+  return AlmostEqualsMatcher<T>{target, n_eps};
 }
 
 
diff --git a/test/runtime/math_test.cpp b/test/runtime/math_test.cpp
index 2a59135b..79018bff 100644
--- a/test/runtime/math_test.cpp
+++ b/test/runtime/math_test.cpp
@@ -448,7 +448,7 @@ TEST_CASE("Angle trigonometric functions", "[trig][angle]")
 
     REQUIRE_THAT(sin(0 * angle[grad]), AlmostEquals(0. * one));
     REQUIRE_THAT(sin(100 * angle[grad]), AlmostEquals(1. * one));
-    REQUIRE_THAT(sin(200 * angle[grad]), AlmostEquals(0. * one));
+    REQUIRE_THAT(sin(200 * angle[grad]), AlmostEquals(0. * one, 2));
     REQUIRE_THAT(sin(300 * angle[grad]), AlmostEquals(-1. * one));
   }
 
@@ -475,7 +475,7 @@ TEST_CASE("Angle trigonometric functions", "[trig][angle]")
     REQUIRE_THAT(tan(0 * angle[grad]), AlmostEquals(0. * one));
     REQUIRE_THAT(tan(50 * angle[grad]), AlmostEquals(1. * one));
     REQUIRE_THAT(tan(150 * angle[grad]), AlmostEquals(-1. * one));
-    REQUIRE_THAT(tan(200 * angle[grad]), AlmostEquals(0. * one));
+    REQUIRE_THAT(tan(200 * angle[grad]), AlmostEquals(0. * one, 2));
   }
 }