From 4b9f352ea1bedd83a775a5623215a360d563186d Mon Sep 17 00:00:00 2001
From: fdai7848 <jan.heidekrueger@informatik.hs-fulda.de>
Date: Sat, 3 Feb 2024 19:42:50 +0100
Subject: [PATCH] add tests for radians function

---
 src/reihen.c       |  2 +-
 src/reihen.h       |  1 +
 test/test_reihen.c | 19 +++++++++++++++++++
 3 files changed, 21 insertions(+), 1 deletion(-)

diff --git a/src/reihen.c b/src/reihen.c
index b31d063..258638c 100644
--- a/src/reihen.c
+++ b/src/reihen.c
@@ -38,7 +38,7 @@ double squashDegreesTo360(double x){
 }
 
 double radians(double d){
-    return d / PI * 180;
+    return d * PI / 180;
 }
 
 double pi(double eps){
diff --git a/src/reihen.h b/src/reihen.h
index 36d8468..19f4b35 100644
--- a/src/reihen.h
+++ b/src/reihen.h
@@ -4,5 +4,6 @@
 double exponential(double x);
 double euler();
 double pi();
+double radians(double d);
 
 #endif // reihen.h
\ No newline at end of file
diff --git a/test/test_reihen.c b/test/test_reihen.c
index 1329b6f..2a30593 100644
--- a/test/test_reihen.c
+++ b/test/test_reihen.c
@@ -44,4 +44,23 @@ void test_pi(void){
     TEST_ASSERT_DOUBLE_WITHIN(0.0000001, 3.14159265, r1);
 }
 
+void test_degrees_to_radians(){
+    double r1, r2, r3, r4;
+
+    r1 = radians(90.0);
+    r2 = radians(180.0);
+    r3 = radians(51.6);
+    r4 = radians(36.97);
+
+    printf("%lf\n", r1);
+    printf("%lf\n", r2);
+    printf("%lf\n", r3);
+    printf("%lf\n", r4);
+
+    TEST_ASSERT_DOUBLE_WITHIN(0.000001, 1.570796, r1);
+    TEST_ASSERT_DOUBLE_WITHIN(0.000001, pi(1e-8), r2);
+    TEST_ASSERT_DOUBLE_WITHIN(0.000001, 0.900589, r3);
+    TEST_ASSERT_DOUBLE_WITHIN(0.000001, 0.645248, r4);
+}
+
 #endif // TEST
\ No newline at end of file