Diff: LowpassFilter.cpp

Revision:

1:d9e840c48b1e

Parent:

0:a9fe4ef404bf

Child:

2:592f01278db4

--- a/LowpassFilter.cpp	Wed Mar 07 14:06:19 2018 +0000
+++ b/LowpassFilter.cpp	Sat Mar 31 16:45:57 2018 +0000
@@ -1,8 +1,8 @@
-/*
- * LowpassFilter.cpp
- * Copyright (c) 2018, ZHAW
- * All rights reserved.
- */
+
+// LowpassFilter.cpp
+// Copyright (c) 2018, ZHAW
+// All rights reserved.
+
 
 #include <cmath>
 #include "LowpassFilter.h"
@@ -12,18 +12,19 @@
 /**
  * Creates a LowpassFilter object with a default cutoff frequency of 1000 [rad/s].
  */
-LowpassFilter::LowpassFilter() {
-    
+LowpassFilter::LowpassFilter()
+{
+
     period = 1.0f;
     frequency = 1000.0f;
-    
+
     a11 = (1.0f+frequency*period)*exp(-frequency*period);
     a12 = period*exp(-frequency*period);
     a21 = -frequency*frequency*period*exp(-frequency*period);
     a22 = (1.0f-frequency*period)*exp(-frequency*period);
     b1 = (1.0f-(1.0f+frequency*period)*exp(-frequency*period))/frequency/frequency;
     b2 = period*exp(-frequency*period);
-    
+
     x1 = 0.0f;
     x2 = 0.0f;
 }
@@ -36,8 +37,9 @@
 /**
  * Resets the filtered value to zero.
  */
-void LowpassFilter::reset() {
-    
+void LowpassFilter::reset()
+{
+
     x1 = 0.0f;
     x2 = 0.0f;
 }
@@ -46,8 +48,9 @@
  * Resets the filtered value to a given value.
  * @param value the value to reset the filter to.
  */
-void LowpassFilter::reset(float value) {
-    
+void LowpassFilter::reset(float value)
+{
+
     x1 = value/frequency/frequency;
     x2 = (x1-a11*x1-b1*value)/a12;
 }
@@ -57,10 +60,11 @@
  * This is typically the sampling period of the periodic task of a controller that uses this filter.
  * @param the sampling period, given in [s].
  */
-void LowpassFilter::setPeriod(float period) {
-    
+void LowpassFilter::setPeriod(float period)
+{
+
     this->period = period;
-    
+
     a11 = (1.0f+frequency*period)*exp(-frequency*period);
     a12 = period*exp(-frequency*period);
     a21 = -frequency*frequency*period*exp(-frequency*period);
@@ -73,10 +77,11 @@
  * Sets the cutoff frequency of this filter.
  * @param frequency the cutoff frequency of the filter in [rad/s].
  */
-void LowpassFilter::setFrequency(float frequency) {
-    
+void LowpassFilter::setFrequency(float frequency)
+{
+
     this->frequency = frequency;
-    
+
     a11 = (1.0f+frequency*period)*exp(-frequency*period);
     a12 = period*exp(-frequency*period);
     a21 = -frequency*frequency*period*exp(-frequency*period);
@@ -89,8 +94,9 @@
  * Gets the current cutoff frequency of this filter.
  * @return the current cutoff frequency in [rad/s].
  */
-float LowpassFilter::getFrequency() {
-    
+float LowpassFilter::getFrequency()
+{
+
     return frequency;
 }
 
@@ -99,13 +105,14 @@
  * @param value the original unfiltered value.
  * @return the filtered value.
  */
-float LowpassFilter::filter(float value) {
+float LowpassFilter::filter(float value)
+{
 
     float x1old = x1;
     float x2old = x2;
-    
+
     x1 = a11*x1old+a12*x2old+b1*value;
     x2 = a21*x1old+a22*x2old+b2*value;
-    
+
     return frequency*frequency*x1;
 }