From ccf733ac95b9340308fcc37968e06676067bd724 Mon Sep 17 00:00:00 2001
From: hazohelet <shimizu2486@bk.ru>
Date: Sun, 7 Jul 2019 23:13:17 +0900
Subject: [PATCH] add angle func

---
 vlib/math/complex.v      |  7 ++++++-
 vlib/math/complex_test.v | 17 ++++++++++++++++-
 2 files changed, 22 insertions(+), 2 deletions(-)

diff --git a/vlib/math/complex.v b/vlib/math/complex.v
index 8925a7021a..87782410b9 100644
--- a/vlib/math/complex.v
+++ b/vlib/math/complex.v
@@ -26,6 +26,11 @@ pub fn (c Complex) str() string {
 	return out
 }
 
+// Complex Angle
+pub fn (c Complex) angle() f64 { 
+	return atan2(c.im, c.re)
+}
+
 // Complex Addition c1 + c2
 pub fn (c1 Complex) + (c2 Complex) Complex {
 	return Complex{c1.re+c2.re,c1.im+c2.im}
@@ -90,4 +95,4 @@ pub fn (c1 Complex) conjugate() Complex{
 // Complex Equals
 pub fn (c1 Complex) equals(c2 Complex) bool {
 	return (c1.re == c2.re) && (c1.im == c2.im)
-}
\ No newline at end of file
+}
diff --git a/vlib/math/complex_test.v b/vlib/math/complex_test.v
index 0407c16dc2..0f2c637d32 100644
--- a/vlib/math/complex_test.v
+++ b/vlib/math/complex_test.v
@@ -101,4 +101,19 @@ fn test_complex_equals() {
 	c1 = math.complex(-3,19)
 	c2 = math.complex(-3,19)
 	assert c1.equals(c2)
-}
\ No newline at end of file
+}
+
+fn test_complex_angle(){
+	mut c := math.complex(1, 0)
+	assert c.angle() * 180 / math.Pi == 0
+	c = math.complex(1, 1)
+	assert c.angle() * 180 / math.Pi == 45
+	c = math.complex(0, 1)
+	assert c.angle() * 180 / math.Pi == 90
+	c = math.complex(-1, 1)
+	assert c.angle() * 180 / math.Pi == 135
+	c = math.complex(-1, -1)
+	assert c.angle() * 180 / math.Pi == -135
+	mut cc := c.conjugate()
+	assert cc.angle() + c.angle() == 0
+}