From 599af17a2a0cc574095f2ec50971928ef5ef3ead Mon Sep 17 00:00:00 2001
From: Frank Mutter <frank@fradcode.de>
Date: Fri, 13 Jul 2018 19:19:06 +0200
Subject: [PATCH] changed q1 and q2 according to the paper of P. Sysel and P.
 Rajmic

---
 c/goertzel/goertzel.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/c/goertzel/goertzel.c b/c/goertzel/goertzel.c
index 2cde63b..19bfdf5 100644
--- a/c/goertzel/goertzel.c
+++ b/c/goertzel/goertzel.c
@@ -29,8 +29,8 @@ float goertzel_mag(int numSamples,float TARGET_FREQUENCY,int SAMPLING_RATE, floa
 
     // calculate the real and imaginary results
     // scaling appropriately
-    real = (q1 - q2 * cosine) / scalingFactor;
-    imag = (q2 * sine) / scalingFactor;
+    real = (q2 - q1 * cosine) / scalingFactor;
+    imag = (q1 * sine) / scalingFactor;
 
     magnitude = sqrtf(real*real + imag*imag);
     return magnitude;
-- 
2.30.2