Preparations for math functions on traces

Software/PC_Application/Application.pro

@@ -25,6 +25,8 @@ HEADERS += \
     SpectrumAnalyzer/tracewidgetsa.h \
     Tools/eseries.h \
     Tools/impedancematchdialog.h \
+    Traces/Math/tracemath.h \
+    Traces/Math/tracematheditdialog.h \
     Traces/fftcomplex.h \
     Traces/markerwidget.h \
     Traces/trace.h \
@@ -77,6 +79,8 @@ SOURCES += \
     SpectrumAnalyzer/tracewidgetsa.cpp \
     Tools/eseries.cpp \
     Tools/impedancematchdialog.cpp \
+    Traces/Math/tracemath.cpp \
+    Traces/Math/tracematheditdialog.cpp \
     Traces/fftcomplex.cpp \
     Traces/markerwidget.cpp \
     Traces/trace.cpp \
@@ -121,6 +125,7 @@ FORMS += \
     Device/manualcontroldialog.ui \
     Generator/signalgenwidget.ui \
     Tools/impedancematchdialog.ui \
+    Traces/Math/tracematheditdialog.ui \
     Traces/markerwidget.ui \
     Traces/smithchartdialog.ui \
     Traces/traceeditdialog.ui \

Software/PC_Application/Calibration/calibration.cpp

@@ -599,21 +599,21 @@ std::vector<Trace *> Calibration::getErrorTermTraces()
     }
     for(auto p : points) {
         Trace::Data d;
-        d.frequency = p.frequency;
+        d.x = p.frequency;
         for(int i=0;i<12;i++) {
             switch(i) {
-            case 0: d.S = p.fe00; break;
+            case 0: d.y = p.fe00; break;
-            case 1: d.S = p.fe11; break;
+            case 1: d.y = p.fe11; break;
-            case 2: d.S = p.fe10e01; break;
+            case 2: d.y = p.fe10e01; break;
-            case 3: d.S = p.fe10e32; break;
+            case 3: d.y = p.fe10e32; break;
-            case 4: d.S = p.fe22; break;
+            case 4: d.y = p.fe22; break;
-            case 5: d.S = p.fe30; break;
+            case 5: d.y = p.fe30; break;
-            case 6: d.S = p.re33; break;
+            case 6: d.y = p.re33; break;
-            case 7: d.S = p.re11; break;
+            case 7: d.y = p.re11; break;
-            case 8: d.S = p.re23e32; break;
+            case 8: d.y = p.re23e32; break;
-            case 9: d.S = p.re23e01; break;
+            case 9: d.y = p.re23e01; break;
-            case 10: d.S = p.re22; break;
+            case 10: d.y = p.re22; break;
-            case 11: d.S = p.re03; break;
+            case 11: d.y = p.re03; break;
             }
             traces[i]->addData(d);
         }

Software/PC_Application/Traces/Math/tracemath.cpp

@@ -0,0 +1,61 @@
+#include "tracemath.h"
+
+TraceMath::TraceMath()
+{
+    input = nullptr;
+    dataType = DataType::Invalid;
+}
+
+TraceMath::Data TraceMath::getSample(unsigned int index)
+{
+    return data.at(index);
+}
+
+unsigned int TraceMath::numSamples()
+{
+    return data.size();
+}
+
+void TraceMath::removeInput()
+{
+    if(input) {
+        // disconnect everything from the input
+        disconnect(input, nullptr, this, nullptr);
+        input = nullptr;
+        data.clear();
+        dataType = DataType::Invalid;
+        emit outputTypeChanged(dataType);
+    }
+}
+
+void TraceMath::assignInput(TraceMath *input)
+{
+    Q_ASSERT(input != nullptr);
+    if(input != this->input) {
+        removeInput();
+        this->input = input;
+        inputTypeChanged(input->dataType);
+        // do initial calculation
+        inputDataChanged();
+        // connect to input
+        connect(input, &TraceMath::outputDataChanged, this, &TraceMath::inputDataChanged);
+        connect(input, &TraceMath::outputSampleChanged, this, &TraceMath::inputSampleChanged);
+        connect(input, &TraceMath::outputTypeChanged, this, &TraceMath::inputTypeChanged);
+    }
+}
+
+void TraceMath::inputTypeChanged(TraceMath::DataType type)
+{
+    auto newType = outputType(type);
+    if(newType != dataType) {
+        dataType = newType;
+        data.clear();
+        inputDataChanged();
+        emit outputTypeChanged(dataType);
+    }
+}
+
+TraceMath::DataType TraceMath::getDataType() const
+{
+    return dataType;
+}

Software/PC_Application/Traces/Math/tracemath.h

@@ -0,0 +1,60 @@
+#ifndef TRACEMATH_H
+#define TRACEMATH_H
+
+#include <QObject>
+#include <vector>
+#include <complex>
+
+class TraceMath : public QObject {
+    Q_OBJECT
+public:
+    TraceMath();
+
+    class Data {
+    public:
+        double x;
+        std::complex<double> y;
+    };
+
+    enum class DataType {
+        Frequency,
+        Time,
+        Invalid,
+    };
+
+    Data getSample(unsigned int index);
+    unsigned int numSamples();
+
+    // indicate whether this function produces time or frequency domain data
+    virtual DataType outputType(DataType inputType) = 0;
+
+    virtual QString description() = 0;
+
+    void removeInput();
+    void assignInput(TraceMath *input);
+
+    DataType getDataType() const;
+    std::vector<Data>& rData() { return data;};
+
+public slots:
+    // a single value of the input data has changed, index determines which sample has changed
+    virtual void inputSampleChanged(unsigned int index){Q_UNUSED(index)};
+    // the complete input data has changed (e.g. cleared or all data modified by some operation)
+    virtual void inputDataChanged(){};
+
+    void inputTypeChanged(DataType type);
+
+signals:
+    // emit this whenever a sample changed (alternatively, if all samples are about to change, emit outputDataChanged after they have changed)
+    void outputSampleChanged(unsigned int index);
+    void outputDataChanged();
+    // emit when the output type changed
+    void outputTypeChanged(DataType type);
+
+protected:
+    std::vector<Data> data;
+    TraceMath *input;
+    DataType dataType;
+};
+
+#endif // TRACEMATH_H

Software/PC_Application/Traces/Math/tracematheditdialog.cpp

@@ -0,0 +1,81 @@
+#include "tracematheditdialog.h"
+#include "ui_tracematheditdialog.h"
+
+TraceMathEditDialog::TraceMathEditDialog(Trace &t, QWidget *parent) :
+    QDialog(parent),
+    ui(new Ui::TraceMathEditDialog)
+{
+    auto model = new MathModel(t);
+    ui->setupUi(this);
+    ui->view->setModel(model);
+}
+
+TraceMathEditDialog::~TraceMathEditDialog()
+{
+    delete ui;
+}
+
+MathModel::MathModel(Trace &t, QObject *parent)
+    : QAbstractTableModel(parent),
+      t(t)
+{
+
+}
+
+int MathModel::rowCount(const QModelIndex &parent) const
+{
+    return t.getMath().size();
+}
+
+int MathModel::columnCount(const QModelIndex &parent) const
+{
+    return ColIndexLast;
+}
+
+QVariant MathModel::data(const QModelIndex &index, int role) const
+{
+    if(!index.isValid()) {
+        return QVariant();
+    }
+    auto math = t.getMath().at(index.row());
+    switch(index.column()) {
+    case ColIndexEnabled:
+        if(role == Qt::CheckStateRole) {
+            return math.enabled ? Qt::Checked : Qt::Unchecked;
+        }
+        break;
+    case ColIndexDescription:
+        if(role == Qt::DisplayRole) {
+            return math.math->description();
+        }
+        break;
+    }
+    return QVariant();
+}
+
+QVariant MathModel::headerData(int section, Qt::Orientation orientation, int role) const
+{
+    if(orientation == Qt::Horizontal && role == Qt::DisplayRole) {
+        switch(section) {
+        case ColIndexEnabled: return "Enabled"; break;
+        case ColIndexDescription: return "Description"; break;
+        default: break;
+        }
+    }
+    return QVariant();
+}
+
+Qt::ItemFlags MathModel::flags(const QModelIndex &index) const
+{
+    int flags = Qt::NoItemFlags;
+    if(index.row() > 1) {
+        // the first entry is always the trace itself and not enabled
+        flags |= Qt::ItemIsEnabled;
+    }
+    switch(index.column()) {
+    case ColIndexEnabled: flags |= Qt::ItemIsUserCheckable; break;
+    default:
+        break;
+    }
+    return (Qt::ItemFlags) flags;
+}

Software/PC_Application/Traces/Math/tracematheditdialog.h

@@ -0,0 +1,46 @@
+#ifndef TRACEMATHEDITDIALOG_H
+#define TRACEMATHEDITDIALOG_H
+
+#include <QDialog>
+#include <QAbstractTableModel>
+#include "Traces/trace.h"
+
+namespace Ui {
+class TraceMathEditDialog;
+}
+
+class MathModel : public QAbstractTableModel
+{
+    Q_OBJECT
+public:
+    MathModel(Trace &t, QObject *parent = 0);
+
+    enum {
+        ColIndexEnabled = 0,
+        ColIndexDescription = 1,
+        ColIndexLast,
+    };
+
+    int rowCount(const QModelIndex &parent = QModelIndex()) const override;
+    int columnCount(const QModelIndex &parent = QModelIndex()) const override;
+    QVariant data(const QModelIndex &index, int role) const override;
+    QVariant headerData(int section, Qt::Orientation orientation, int role = Qt::DisplayRole) const override;
+    Qt::ItemFlags flags(const QModelIndex &index) const override;
+
+private:
+    Trace &t;
+};
+
+class TraceMathEditDialog : public QDialog
+{
+    Q_OBJECT
+
+public:
+    explicit TraceMathEditDialog(Trace &t, QWidget *parent = nullptr);
+    ~TraceMathEditDialog();
+
+private:
+    Ui::TraceMathEditDialog *ui;
+};
+
+#endif // TRACEMATHEDITDIALOG_H

Software/PC_Application/Traces/Math/tracematheditdialog.ui

@@ -0,0 +1,130 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<ui version="4.0">
+ <class>TraceMathEditDialog</class>
+ <widget class="QDialog" name="TraceMathEditDialog">
+  <property name="geometry">
+   <rect>
+    <x>0</x>
+    <y>0</y>
+    <width>411</width>
+    <height>302</height>
+   </rect>
+  </property>
+  <property name="windowTitle">
+   <string>Math functions</string>
+  </property>
+  <property name="modal">
+   <bool>true</bool>
+  </property>
+  <layout class="QVBoxLayout" name="verticalLayout_2">
+   <item>
+    <layout class="QHBoxLayout" name="horizontalLayout">
+     <item>
+      <widget class="QTableView" name="view">
+       <property name="selectionBehavior">
+        <enum>QAbstractItemView::SelectRows</enum>
+       </property>
+       <attribute name="horizontalHeaderMinimumSectionSize">
+        <number>20</number>
+       </attribute>
+       <attribute name="horizontalHeaderDefaultSectionSize">
+        <number>70</number>
+       </attribute>
+       <attribute name="horizontalHeaderStretchLastSection">
+        <bool>true</bool>
+       </attribute>
+       <attribute name="verticalHeaderVisible">
+        <bool>false</bool>
+       </attribute>
+      </widget>
+     </item>
+     <item>
+      <layout class="QVBoxLayout" name="verticalLayout">
+       <item>
+        <widget class="QPushButton" name="bAdd">
+         <property name="sizePolicy">
+          <sizepolicy hsizetype="Fixed" vsizetype="Fixed">
+           <horstretch>0</horstretch>
+           <verstretch>0</verstretch>
+          </sizepolicy>
+         </property>
+         <property name="toolTip">
+          <string>Add</string>
+         </property>
+         <property name="text">
+          <string/>
+         </property>
+         <property name="icon">
+          <iconset theme="list-add" resource="../../icons.qrc">
+           <normaloff>:/icons/add.png</normaloff>:/icons/add.png</iconset>
+         </property>
+        </widget>
+       </item>
+       <item>
+        <widget class="QPushButton" name="bDelete">
+         <property name="sizePolicy">
+          <sizepolicy hsizetype="Fixed" vsizetype="Fixed">
+           <horstretch>0</horstretch>
+           <verstretch>0</verstretch>
+          </sizepolicy>
+         </property>
+         <property name="toolTip">
+          <string>Delete</string>
+         </property>
+         <property name="text">
+          <string/>
+         </property>
+         <property name="icon">
+          <iconset theme="list-remove" resource="../../icons.qrc">
+           <normaloff>:/icons/remove.png</normaloff>:/icons/remove.png</iconset>
+         </property>
+        </widget>
+       </item>
+       <item>
+        <spacer name="verticalSpacer">
+         <property name="orientation">
+          <enum>Qt::Vertical</enum>
+         </property>
+         <property name="sizeHint" stdset="0">
+          <size>
+           <width>18</width>
+           <height>186</height>
+          </size>
+         </property>
+        </spacer>
+       </item>
+      </layout>
+     </item>
+    </layout>
+   </item>
+   <item>
+    <widget class="QDialogButtonBox" name="buttonBox">
+     <property name="standardButtons">
+      <set>QDialogButtonBox::Ok</set>
+     </property>
+    </widget>
+   </item>
+  </layout>
+ </widget>
+ <resources>
+  <include location="../../icons.qrc"/>
+ </resources>
+ <connections>
+  <connection>
+   <sender>buttonBox</sender>
+   <signal>accepted()</signal>
+   <receiver>TraceMathEditDialog</receiver>
+   <slot>accept()</slot>
+   <hints>
+    <hint type="sourcelabel">
+     <x>216</x>
+     <y>280</y>
+    </hint>
+    <hint type="destinationlabel">
+     <x>216</x>
+     <y>150</y>
+    </hint>
+   </hints>
+  </connection>
+ </connections>
+</ui>

Software/PC_Application/Traces/trace.cpp

@@ -14,9 +14,12 @@ Trace::Trace(QString name, QColor color, LiveParameter live)
       visible(true),
       paused(false),
       touchstone(false),
-      calibration(false)
+      calibration(false),
+      lastMath(nullptr)
 {
-
+    MathInfo self = {.math = this, .enabled = true};
+    math.push_back(self);
+    updateLastMath(math.rbegin());
 }
 
 Trace::~Trace()
@@ -28,21 +31,21 @@ void Trace::clear() {
     if(paused) {
         return;
     }
-    _data.clear();
+    data.clear();
     settings.valid = false;
     emit cleared(this);
-    emit dataChanged();
+    emit outputDataChanged();
 }
 
 void Trace::addData(const Trace::Data& d) {
     // add or replace data in vector while keeping it sorted with increasing frequency
-    auto lower = lower_bound(_data.begin(), _data.end(), d, [](const Data &lhs, const Data &rhs) -> bool {
+    auto lower = lower_bound(data.begin(), data.end(), d, [](const Data &lhs, const Data &rhs) -> bool {
-        return lhs.frequency < rhs.frequency;
+        return lhs.x < rhs.x;
     });
-    if(lower == _data.end()) {
+    if(lower == data.end()) {
         // highest frequency yet, add to vector
-        _data.push_back(d);
+        data.push_back(d);
-    } else if(lower->frequency == d.frequency) {
+    } else if(lower->x == d.x) {
         switch(_liveType) {
         case LivedataType::Overwrite:
             // replace this data element
@@ -50,13 +53,13 @@ void Trace::addData(const Trace::Data& d) {
             break;
         case LivedataType::MaxHold:
             // replace this data element
-            if(abs(d.S) > abs(lower->S)) {
+            if(abs(d.y) > abs(lower->y)) {
                 *lower = d;
             }
             break;
         case LivedataType::MinHold:
             // replace this data element
-            if(abs(d.S) < abs(lower->S)) {
+            if(abs(d.y) < abs(lower->y)) {
                 *lower = d;
             }
             break;
@@ -64,11 +67,10 @@ void Trace::addData(const Trace::Data& d) {
 
     } else {
         // insert at this position
-        _data.insert(lower, d);
+        data.insert(lower, d);
     }
-    emit dataAdded(this, d);
+    emit outputSampleChanged(lower - data.begin());
-    emit dataChanged();
+    if(lower == data.begin()) {
-    if(lower == _data.begin()) {
         // received the first point, which means the last sweep just finished
         if(tdr_users) {
             updateTimeDomainData();
@@ -106,8 +108,8 @@ void Trace::fillFromTouchstone(Touchstone &t, unsigned int parameter, QString fi
     for(unsigned int i=0;i<t.points();i++) {
         auto tData = t.point(i);
         Data d;
-        d.frequency = tData.frequency;
+        d.x = tData.frequency;
-        d.S = t.point(i).S[parameter];
+        d.y = t.point(i).S[parameter];
         addData(d);
     }
     // check if parameter is square (e.i. S11/S22/S33/...)
@@ -174,7 +176,7 @@ void Trace::updateTimeDomainData()
     auto firstStep = minFreq();
     if(firstStep == 0) {
         // zero as first step would result in infinite number of points, skip and start with second
-        firstStep = _data[1].frequency;
+        firstStep = lastMath->rData()[1].x;
         steps--;
     }
     if(firstStep * steps != maxFreq()) {
@@ -226,7 +228,34 @@ void Trace::updateTimeDomainData()
 //    auto duration = duration_cast< milliseconds >(
 //        system_clock::now().time_since_epoch()
 //    ).count() - starttime;
-//    cout << "TDR: " << this << " (took " << duration << "ms)" <<endl;
+    //    cout << "TDR: " << this << " (took " << duration << "ms)" <<endl;
+}
+
+const std::vector<Trace::MathInfo>& Trace::getMath() const
+{
+    return math;
+}
+
+void Trace::updateLastMath(vector<MathInfo>::reverse_iterator start)
+{
+    TraceMath *newLast = nullptr;
+    for(auto it = start;it != math.rend();it++) {
+        if(it->enabled) {
+            newLast = it->math;
+            break;
+        }
+    }
+    Q_ASSERT(newLast != nullptr);
+    if(newLast != lastMath) {
+        if(lastMath != nullptr) {
+            disconnect(lastMath, &TraceMath::outputDataChanged, this, nullptr);
+            disconnect(lastMath, &TraceMath::outputSampleChanged, this, nullptr);
+        }
+        lastMath = newLast;
+        // relay signals of end of math chain
+        connect(lastMath, &TraceMath::outputDataChanged, this, &Trace::dataChanged);
+        connect(lastMath, &TraceMath::outputSampleChanged, this, &Trace::dataChanged);
+    }
 }
 
 void Trace::setReflection(bool value)
@@ -305,6 +334,11 @@ Trace::TimedomainData Trace::getTDR(double position)
     }
 }
 
+QString Trace::description()
+{
+    return name() + ": measured data";
+}
+
 void Trace::setCalibration(bool value)
 {
     calibration = value;
@@ -363,16 +397,55 @@ bool Trace::isReflection()
     return reflection;
 }
 
+bool Trace::mathEnabled()
+{
+    return lastMath != this;
+}
+
+bool Trace::hasMathOperations()
+{
+    return math.size() > 1;
+}
+
+void Trace::enableMath(bool enable)
+{
+    auto start = enable ? math.rbegin() : make_reverse_iterator(math.begin());
+    updateLastMath(start);
+}
+
+unsigned int Trace::size()
+{
+    return lastMath->numSamples();
+}
+
+double Trace::minFreq()
+{
+    if(size() > 0) {
+        return data.front().x;
+    } else {
+        return 0.0;
+    }
+}
+
+double Trace::maxFreq()
+{
+    if(size() > 0) {
+        return data.back().x;
+    } else {
+        return 0.0;
+    }
+}
+
 double Trace::findExtremumFreq(bool max)
 {
     double compare = max ? numeric_limits<double>::min() : numeric_limits<double>::max();
     double freq = 0.0;
-    for(auto d : _data) {
+    for(auto sample : lastMath->rData()) {
-        double amplitude = abs(d.S);
+        double amplitude = abs(sample.y);
         if((max && (amplitude > compare)) || (!max && (amplitude < compare))) {
             // higher/lower extremum found
             compare = amplitude;
-            freq = d.frequency;
+            freq = sample.x;
         }
     }
     return freq;
@@ -388,11 +461,11 @@ std::vector<double> Trace::findPeakFrequencies(unsigned int maxPeaks, double min
     double frequency = 0.0;
     double max_dbm = -200.0;
     double min_dbm = 200.0;
-    for(auto d : _data) {
+    for(auto d : lastMath->rData()) {
-        double dbm = 20*log10(abs(d.S));
+        double dbm = 20*log10(abs(d.y));
         if((dbm >= max_dbm) && (min_dbm <= dbm - minValley)) {
             // potential peak frequency
-            frequency = d.frequency;
+            frequency = d.x;
             max_dbm = dbm;
         }
         if(dbm <= min_dbm) {
@@ -430,6 +503,11 @@ std::vector<double> Trace::findPeakFrequencies(unsigned int maxPeaks, double min
     return frequencies;
 }
 
+Trace::Data Trace::sample(unsigned int index)
+{
+    return lastMath->getSample(index);
+}
+
 QString Trace::getTouchstoneFilename() const
 {
     return touchstoneFilename;
@@ -447,19 +525,19 @@ unsigned int Trace::getTouchstoneParameter() const
 
 std::complex<double> Trace::getData(double frequency)
 {
-    if(_data.size() == 0 || frequency < minFreq() || frequency > maxFreq()) {
+    if(lastMath->numSamples() == 0 || frequency < minFreq() || frequency > maxFreq()) {
         return std::numeric_limits<std::complex<double>>::quiet_NaN();
     }
 
     auto i = index(frequency);
-    if(_data.at(i).frequency == frequency) {
+    if(lastMath->getSample(i).x == frequency) {
-        return _data[i].S;
+        return lastMath->getSample(i).y;
     } else {
         // no exact frequency match, needs to interpolate
-        auto high = _data[i];
+        auto high = lastMath->getSample(i);
-        auto low = _data[i-1];
+        auto low = lastMath->getSample(i - 1);
-        double alpha = (frequency - low.frequency) / (high.frequency - low.frequency);
+        double alpha = (frequency - low.x) / (high.x - low.x);
-        return low.S * (1 - alpha) + high.S * alpha;
+        return low.y * (1 - alpha) + high.y * alpha;
     }
 }
 
@@ -478,10 +556,10 @@ double Trace::getNoise(double frequency)
 
 int Trace::index(double frequency)
 {
-    auto lower = lower_bound(_data.begin(), _data.end(), frequency, [](const Data &lhs, const double freq) -> bool {
+    auto lower = lower_bound(lastMath->rData().begin(), lastMath->rData().end(), frequency, [](const Data &lhs, const double freq) -> bool {
-        return lhs.frequency < freq;
+        return lhs.x < freq;
     });
-    return lower - _data.begin();
+    return lower - lastMath->rData().begin();
 }
 
 void Trace::setTouchstoneParameter(int value)

Software/PC_Application/Traces/trace.h

@@ -8,19 +8,16 @@
 #include <set>
 #include "touchstone.h"
 #include "Device/device.h"
+#include "Math/tracemath.h"
 
 class TraceMarker;
 
-class Trace : public QObject
+class Trace : public TraceMath
 {
     Q_OBJECT
 public:
 
-    class Data {
+    using Data = TraceMath::Data;
-    public:
-        double frequency;
-        std::complex<double> S;
-    };
 
     class TimedomainData {
     public:
@@ -67,11 +64,14 @@ public:
     bool isCalibration();
     bool isLive();
     bool isReflection();
+    bool mathEnabled(); // check if math operations are enabled
+    bool hasMathOperations(); // check if math operations are set up (not necessarily enabled)
+    void enableMath(bool enable);
     LiveParameter liveParameter() { return _liveParam; }
     LivedataType liveType() { return _liveType; }
-    unsigned int size() { return _data.size(); }
+    unsigned int size();
-    double minFreq() { return size() > 0 ? _data.front().frequency : 0.0; };
+    double minFreq();
-    double maxFreq() { return size() > 0 ? _data.back().frequency : 0.0; };
+    double maxFreq();
     double findExtremumFreq(bool max);
     /* Searches for peaks in the trace data and returns the peak frequencies in ascending order.
      * Up to maxPeaks will be returned, with higher level peaks taking priority over lower level peaks.
@@ -79,7 +79,7 @@ public:
      * To detect the next peak, the signal first has to drop at least minValley below the peak level.
      */
     std::vector<double> findPeakFrequencies(unsigned int maxPeaks = 100, double minLevel = -100.0, double minValley = 3.0);
-    Data sample(unsigned int index) { return _data.at(index); }
+    Data sample(unsigned int index);
     QString getTouchstoneFilename() const;
     unsigned int getTouchstoneParameter() const;
     std::complex<double> getData(double frequency);
@@ -103,6 +103,16 @@ public:
     // Since the usual delay values are way smaller than the distance values this should work
     TimedomainData getTDR(double position);
 
+    DataType outputType(DataType inputType) override { Q_UNUSED(inputType) return DataType::Frequency;};
+    QString description() override;
+
+    class MathInfo {
+    public:
+        TraceMath *math;
+        bool enabled;
+    };
+    const std::vector<MathInfo>& getMath() const;
+
 public slots:
     void setTouchstoneParameter(int value);
     void setTouchstoneFilename(const QString &value);
@@ -115,7 +125,6 @@ private:
 signals:
     void cleared(Trace *t);
     void typeChanged(Trace *t);
-    void dataAdded(Trace *t, Data d);
     void deleted(Trace *t);
     void visibilityChanged(Trace *t);
     void dataChanged();
@@ -128,7 +137,7 @@ signals:
 private:
     void updateTimeDomainData();
     void printTimeDomain();
-    std::vector<Data> _data;
+//    std::vector<Data> _data;
     std::vector<TimedomainData> timeDomain;
     unsigned int tdr_users;
     QString _name;
@@ -150,6 +159,10 @@ private:
         };
         bool valid;
     } settings;
+
+    std::vector<MathInfo> math;
+    TraceMath *lastMath;
+    void updateLastMath(std::vector<MathInfo>::reverse_iterator start);
 };
 
 #endif // TRACE_H

Software/PC_Application/Traces/traceeditdialog.cpp

@@ -2,6 +2,7 @@
 #include "ui_traceeditdialog.h"
 #include <QColorDialog>
 #include <QFileDialog>
+#include "Math/tracematheditdialog.h"
 
 TraceEditDialog::TraceEditDialog(Trace &t, QWidget *parent) :
     QDialog(parent),
@@ -92,6 +93,10 @@ TraceEditDialog::TraceEditDialog(Trace &t, QWidget *parent) :
     connect(ui->GSource, qOverload<int>(&QButtonGroup::buttonClicked), updateFileStatus);
     connect(ui->touchstoneImport, &TouchstoneImport::statusChanged, updateFileStatus);
     connect(ui->touchstoneImport, &TouchstoneImport::filenameChanged, updateFileStatus);
+    connect(ui->mathSetup, &QPushButton::clicked, [&](){
+        auto dialog = new TraceMathEditDialog(t);
+        dialog->show();
+    });
 
     updateFileStatus();
 }

Software/PC_Application/Traces/traceeditdialog.ui

@@ -37,6 +37,8 @@
       </widget>
      </item>
      <item row="1" column="1">
+      <layout class="QHBoxLayout" name="horizontalLayout_3">
+       <item>
         <widget class="ColorPickerButton" name="color">
          <property name="sizePolicy">
           <sizepolicy hsizetype="Fixed" vsizetype="Fixed">
@@ -49,6 +51,15 @@
          </property>
         </widget>
        </item>
+       <item>
+        <widget class="QPushButton" name="mathSetup">
+         <property name="text">
+          <string>Math</string>
+         </property>
+        </widget>
+       </item>
+      </layout>
+     </item>
     </layout>
    </item>
    <item>

Software/PC_Application/Traces/traceexportdialog.cpp

@@ -72,9 +72,9 @@ void TraceExportDialog::on_buttonBox_accepted()
                     } else {
                         Trace *t = qvariant_cast<Trace*>(cTraces[i][j]->itemData(cTraces[i][j]->currentIndex()));
                         // extract frequency (will overwrite for each trace but all traces have the same frequency points anyway)
-                        tData.frequency = t->sample(s).frequency;
+                        tData.frequency = t->sample(s).x;
                         // add S parameter from trace to touchstone
-                        tData.S.push_back(t->sample(s).S);
+                        tData.S.push_back(t->sample(s).y);
                     }
                 }
             }

Software/PC_Application/Traces/tracemarker.cpp

@@ -695,11 +695,11 @@ void TraceMarker::update()
             setPosition(peakFreq);
             // find the cutoff frequency
             auto index = parentTrace->index(peakFreq);
-            auto peakAmplitude = 20*log10(abs(parentTrace->sample(index).S));
+            auto peakAmplitude = 20*log10(abs(parentTrace->sample(index).y));
             auto cutoff = peakAmplitude + cutoffAmplitude;
             int inc = type == Type::Lowpass ? 1 : -1;
             while(index >= 0 && index < (int) parentTrace->size()) {
-                auto amplitude = 20*log10(abs(parentTrace->sample(index).S));
+                auto amplitude = 20*log10(abs(parentTrace->sample(index).y));
                 if(amplitude <= cutoff) {
                     break;
                 }
@@ -711,7 +711,7 @@ void TraceMarker::update()
                 index = parentTrace->size() - 1;
             }
             // set position of cutoff marker
-            helperMarkers[0]->setPosition(parentTrace->sample(index).frequency);
+            helperMarkers[0]->setPosition(parentTrace->sample(index).x);
         }
         break;
     case Type::Bandpass:
@@ -725,12 +725,12 @@ void TraceMarker::update()
             setPosition(peakFreq);
             // find the cutoff frequencies
             auto index = parentTrace->index(peakFreq);
-            auto peakAmplitude = 20*log10(abs(parentTrace->sample(index).S));
+            auto peakAmplitude = 20*log10(abs(parentTrace->sample(index).y));
             auto cutoff = peakAmplitude + cutoffAmplitude;
 
             auto low_index = index;
             while(low_index >= 0) {
-                auto amplitude = 20*log10(abs(parentTrace->sample(low_index).S));
+                auto amplitude = 20*log10(abs(parentTrace->sample(low_index).y));
                 if(amplitude <= cutoff) {
                     break;
                 }
@@ -740,11 +740,11 @@ void TraceMarker::update()
                 low_index = 0;
             }
             // set position of cutoff marker
-            helperMarkers[0]->setPosition(parentTrace->sample(low_index).frequency);
+            helperMarkers[0]->setPosition(parentTrace->sample(low_index).x);
 
             auto high_index = index;
             while(high_index < (int) parentTrace->size()) {
-                auto amplitude = 20*log10(abs(parentTrace->sample(high_index).S));
+                auto amplitude = 20*log10(abs(parentTrace->sample(high_index).y));
                 if(amplitude <= cutoff) {
                     break;
                 }
@@ -754,7 +754,7 @@ void TraceMarker::update()
                 high_index = parentTrace->size() - 1;
             }
             // set position of cutoff marker
-            helperMarkers[1]->setPosition(parentTrace->sample(high_index).frequency);
+            helperMarkers[1]->setPosition(parentTrace->sample(high_index).x);
             // set center marker inbetween cutoff markers
             helperMarkers[2]->setPosition((helperMarkers[0]->position + helperMarkers[1]->position) / 2);
         }

Software/PC_Application/Traces/tracemodel.cpp

@@ -52,7 +52,7 @@ void TraceModel::toggleVisibility(unsigned int index)
 {
     if (index < traces.size()) {
         traces[index]->setVisible(!traces[index]->isVisible());
-        emit dataChanged(createIndex(index, 0), createIndex(index, 0));
+        emit dataChanged(createIndex(index, ColIndexVisible), createIndex(index, ColIndexVisible));
     }
 }
 
@@ -64,11 +64,23 @@ void TraceModel::togglePause(unsigned int index)
         } else {
             traces[index]->pause();
         }
-        emit dataChanged(createIndex(index, 1), createIndex(index, 1));
+        emit dataChanged(createIndex(index, ColIndexPlayPause), createIndex(index, ColIndexPlayPause));
         emit requiredExcitation(PortExcitationRequired(1), PortExcitationRequired(2));
     }
 }
 
+void TraceModel::toggleMath(unsigned int index)
+{
+    if (index >= traces.size()) {
+        return;
+    }
+    auto trace = traces[index];
+    if(trace->hasMathOperations()) {
+        trace->enableMath(!trace->mathEnabled());
+        emit dataChanged(createIndex(index, ColIndexMath), createIndex(index, ColIndexMath));
+    }
+}
+
 int TraceModel::rowCount(const QModelIndex &) const
 {
     return traces.size();
@@ -76,7 +88,7 @@ int TraceModel::rowCount(const QModelIndex &) const
 
 int TraceModel::columnCount(const QModelIndex &) const
 {
-    return 3;
+    return ColIndexLast;
 }
 
 QVariant TraceModel::data(const QModelIndex &index, int role) const
@@ -86,37 +98,47 @@ QVariant TraceModel::data(const QModelIndex &index, int role) const
 
     if ((unsigned int) index.row() >= traces.size())
         return QVariant();
-    if (index.column() == 0) {
+
+    auto trace = traces[index.row()];
+    switch(index.column()) {
+    case ColIndexVisible:
         if (role == Qt::DecorationRole) {
-            if (traces[index.row()]->isVisible()) {
+            if (trace->isVisible()) {
                 return QIcon(":/icons/visible.svg");
             } else {
                 return QIcon(":/icons/invisible.svg");
             }
-        } else {
-            return QVariant();
         }
-    } else if (index.column() == 1) {
+        break;
-        if (role == Qt::DecorationRole && !traces[index.row()]->isTouchstone()) {
+    case ColIndexPlayPause:
-            if (traces[index.row()]->isPaused()) {
+        if (role == Qt::DecorationRole && !trace->isTouchstone()) {
+            if (trace->isPaused()) {
                 return QIcon(":/icons/pause.svg");
             } else {
                 return QIcon(":/icons/play.svg");
             }
-        } else {
-            return QVariant();
         }
-    } else if (index.column() == 2) {
+        break;
+    case ColIndexMath:
+        if (role == Qt::DecorationRole && trace->hasMathOperations()) {
+            if(trace->mathEnabled()) {
+                return QIcon(":icons/math_enabled");
+            } else {
+                return QIcon(":icons/math_disabled");
+            }
+        }
+        break;
+    case ColIndexName:
         if (role == Qt::DisplayRole) {
-            return traces[index.row()]->name();
+            return trace->name();
         } else if (role == Qt::ForegroundRole) {
-            return traces[index.row()]->color();
+            return trace->color();
-        } else {
-            return QVariant();
         }
-    } else {
+        break;
-        return QVariant();
+    default:
+        break;
     }
+    return QVariant();
 }
 
 std::vector<Trace *> TraceModel::getTraces()
@@ -156,12 +178,12 @@ void TraceModel::addVNAData(const Protocol::Datapoint &d, const Protocol::SweepS
     for(auto t : traces) {
         if (t->isLive() && !t->isPaused()) {
             Trace::Data td;
-            td.frequency = d.frequency;
+            td.x = d.frequency;
             switch(t->liveParameter()) {
-            case Trace::LiveParameter::S11: td.S = complex<double>(d.real_S11, d.imag_S11); break;
+            case Trace::LiveParameter::S11: td.y = complex<double>(d.real_S11, d.imag_S11); break;
-            case Trace::LiveParameter::S12: td.S = complex<double>(d.real_S12, d.imag_S12); break;
+            case Trace::LiveParameter::S12: td.y = complex<double>(d.real_S12, d.imag_S12); break;
-            case Trace::LiveParameter::S21: td.S = complex<double>(d.real_S21, d.imag_S21); break;
+            case Trace::LiveParameter::S21: td.y = complex<double>(d.real_S21, d.imag_S21); break;
-            case Trace::LiveParameter::S22: td.S = complex<double>(d.real_S22, d.imag_S22); break;
+            case Trace::LiveParameter::S22: td.y = complex<double>(d.real_S22, d.imag_S22); break;
             default:
                 // not a VNA trace, skip
                 continue;
@@ -176,10 +198,10 @@ void TraceModel::addSAData(const Protocol::SpectrumAnalyzerResult& d, const Prot
     for(auto t : traces) {
         if (t->isLive() && !t->isPaused()) {
             Trace::Data td;
-            td.frequency = d.frequency;
+            td.x = d.frequency;
             switch(t->liveParameter()) {
-            case Trace::LiveParameter::Port1: td.S = complex<double>(d.port1, 0); break;
+            case Trace::LiveParameter::Port1: td.y = complex<double>(d.port1, 0); break;
-            case Trace::LiveParameter::Port2: td.S = complex<double>(d.port2, 0); break;
+            case Trace::LiveParameter::Port2: td.y = complex<double>(d.port2, 0); break;
             default:
                 // not a SA trace, skip
                 continue;

Software/PC_Application/Traces/tracemodel.h

@@ -13,11 +13,20 @@ public:
     TraceModel(QObject *parent = 0);
     ~TraceModel();
 
+    enum {
+        ColIndexVisible = 0,
+        ColIndexPlayPause = 1,
+        ColIndexMath = 2,
+        ColIndexName = 3,
+        ColIndexLast,
+    };
+
     void addTrace(Trace *t);
     void removeTrace(unsigned int index);
     Trace *trace(unsigned int index);
     void toggleVisibility(unsigned int index);
     void togglePause(unsigned int index);
+    void toggleMath(unsigned int index);
 
     int rowCount(const QModelIndex &parent = QModelIndex()) const override;
     int columnCount(const QModelIndex &parent = QModelIndex()) const override;

Software/PC_Application/Traces/tracesmithchart.cpp

@@ -41,10 +41,10 @@ void TraceSmithChart::axisSetupDialog()
 
 QPoint TraceSmithChart::dataToPixel(Trace::Data d)
 {
-    if(d.frequency < sweep_fmin || d.frequency > sweep_fmax) {
+    if(d.x < sweep_fmin || d.x > sweep_fmax) {
         return QPoint();
     }
-    return transform.map(QPoint(d.S.real() * smithCoordMax, -d.S.imag() * smithCoordMax));
+    return transform.map(QPoint(d.y.real() * smithCoordMax, -d.y.imag() * smithCoordMax));
 }
 
 std::complex<double> TraceSmithChart::pixelToData(QPoint p)
@@ -83,7 +83,7 @@ double TraceSmithChart::nearestTracePoint(Trace *t, QPoint pixel)
             closestIndex = i;
         }
     }
-    return t->sample(closestIndex).frequency;
+    return t->sample(closestIndex).x;
 }
 
 void TraceSmithChart::draw(QPainter &p) {
@@ -144,17 +144,17 @@ void TraceSmithChart::draw(QPainter &p) {
         for(int i=1;i<nPoints;i++) {
             auto last = trace->sample(i-1);
             auto now = trace->sample(i);
-            if (limitToSpan && (last.frequency < sweep_fmin || now.frequency > sweep_fmax)) {
+            if (limitToSpan && (last.x < sweep_fmin || now.x > sweep_fmax)) {
                 continue;
             }
-            if(isnan(now.S.real())) {
+            if(isnan(now.y.real())) {
                 break;
             }
             // scale to size of smith diagram
-            last.S *= smithCoordMax;
+            last.y *= smithCoordMax;
-            now.S *= smithCoordMax;
+            now.y *= smithCoordMax;
             // draw line
-            p.drawLine(std::real(last.S), -std::imag(last.S), std::real(now.S), -std::imag(now.S));
+            p.drawLine(std::real(last.y), -std::imag(last.y), std::real(now.y), -std::imag(now.y));
         }
         if(trace->size() > 0) {
             // only draw markers if the trace has at least one point

Software/PC_Application/Traces/tracewidget.cpp

@@ -109,7 +109,7 @@ void TraceWidget::on_edit_clicked()
 
 void TraceWidget::on_view_doubleClicked(const QModelIndex &index)
 {
-    if(index.column() == 2) {
+    if(index.column() == TraceModel::ColIndexName) {
         auto edit = new TraceEditDialog(*model.trace(index.row()));
         edit->show();
     }
@@ -117,9 +117,17 @@ void TraceWidget::on_view_doubleClicked(const QModelIndex &index)
 
 void TraceWidget::on_view_clicked(const QModelIndex &index)
 {
-    if(index.column()==0) {
+    switch(index.column()) {
+    case TraceModel::ColIndexVisible:
         model.toggleVisibility(index.row());
-    } else if(index.column()==1) {
+        break;
+    case TraceModel::ColIndexPlayPause:
         model.togglePause(index.row());
+        break;
+    case TraceModel::ColIndexMath:
+        model.toggleMath(index.row());
+        break;
+    default:
+        break;
     }
 }

Software/PC_Application/Traces/tracexyplot.cpp

@@ -654,8 +654,8 @@ QPointF TraceXYPlot::transformY(Trace *t, unsigned int sample, TraceXYPlot::YAxi
     case YAxisType::Phase:
     case YAxisType::VSWR: {
         auto d = t->sample(sample);
-        ret.setY(transformY(d.S, type));
+        ret.setY(transformY(d.y, type));
-        ret.setX(d.frequency);
+        ret.setX(d.x);
     }
         break;
     case YAxisType::Impulse:
@@ -702,12 +702,12 @@ unsigned int TraceXYPlot::numTraceSamples(Trace *t)
 
 QPoint TraceXYPlot::dataToPixel(Trace::Data d)
 {
-    if(d.frequency < XAxis.rangeMin || d.frequency > XAxis.rangeMax) {
+    if(d.x < XAxis.rangeMin || d.x > XAxis.rangeMax) {
         return QPoint();
     }
-    auto y = transformY(d.S, YAxis[0].type);
+    auto y = transformY(d.y, YAxis[0].type);
     QPoint p;
-    p.setX(Util::Scale<double>(d.frequency, XAxis.rangeMin, XAxis.rangeMax, plotAreaLeft, plotAreaLeft + plotAreaWidth));
+    p.setX(Util::Scale<double>(d.x, XAxis.rangeMin, XAxis.rangeMax, plotAreaLeft, plotAreaLeft + plotAreaWidth));
     p.setY(Util::Scale<double>(y, YAxis[0].rangeMin, YAxis[0].rangeMax, plotAreaBottom, 0));
     return p;
 }
@@ -842,5 +842,6 @@ QString TraceXYPlot::AxisUnit(TraceXYPlot::XAxisType type)
     case XAxisType::Frequency: return "Hz"; break;
     case XAxisType::Time: return "s"; break;
     case XAxisType::Distance: return "m"; break;
+    default: return ""; break;
     }
 }

Software/PC_Application/icons.qrc

@@ -33,5 +33,7 @@
         <file>icons/zoom-fit.png</file>
         <file>icons/zoom-in.png</file>
         <file>icons/zoom-out.png</file>
+        <file>icons/math_disabled.svg</file>
+        <file>icons/math_enabled.svg</file>
     </qresource>
 </RCC>

Software/PC_Application/icons/math_disabled.svg

@@ -0,0 +1,84 @@
+<?xml version="1.0" encoding="UTF-8" standalone="no"?>
+<!-- Created with Inkscape (http://www.inkscape.org/) -->
+
+<svg
+   xmlns:dc="http://purl.org/dc/elements/1.1/"
+   xmlns:cc="http://creativecommons.org/ns#"
+   xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#"
+   xmlns:svg="http://www.w3.org/2000/svg"
+   xmlns="http://www.w3.org/2000/svg"
+   xmlns:sodipodi="http://sodipodi.sourceforge.net/DTD/sodipodi-0.dtd"
+   xmlns:inkscape="http://www.inkscape.org/namespaces/inkscape"
+   width="17.410528mm"
+   height="9.36625mm"
+   viewBox="0 0 17.410529 9.3662499"
+   version="1.1"
+   id="svg8"
+   inkscape:version="0.92.3 (2405546, 2018-03-11)"
+   sodipodi:docname="math_disabled.svg">
+  <defs
+     id="defs2" />
+  <sodipodi:namedview
+     id="base"
+     pagecolor="#ffffff"
+     bordercolor="#666666"
+     borderopacity="1.0"
+     inkscape:pageopacity="0.0"
+     inkscape:pageshadow="2"
+     inkscape:zoom="5.6"
+     inkscape:cx="43.034455"
+     inkscape:cy="-5.145459"
+     inkscape:document-units="mm"
+     inkscape:current-layer="layer1"
+     showgrid="false"
+     inkscape:window-width="1853"
+     inkscape:window-height="1025"
+     inkscape:window-x="1147"
+     inkscape:window-y="867"
+     inkscape:window-maximized="1" />
+  <metadata
+     id="metadata5">
+    <rdf:RDF>
+      <cc:Work
+         rdf:about="">
+        <dc:format>image/svg+xml</dc:format>
+        <dc:type
+           rdf:resource="http://purl.org/dc/dcmitype/StillImage" />
+        <dc:title></dc:title>
+      </cc:Work>
+    </rdf:RDF>
+  </metadata>
+  <g
+     inkscape:label="Layer 1"
+     inkscape:groupmode="layer"
+     id="layer1"
+     transform="translate(-77.99312,-144.11468)">
+    <text
+       xml:space="preserve"
+       style="font-style:normal;font-variant:normal;font-weight:normal;font-stretch:normal;font-size:10.58333302px;line-height:125%;font-family:'Latin Modern Math';-inkscape-font-specification:'Latin Modern Math';letter-spacing:0px;word-spacing:0px;fill:#000000;fill-opacity:1;stroke:none;stroke-width:0.26458332px;stroke-linecap:butt;stroke-linejoin:miter;stroke-opacity:1"
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+       y="158.66071"
+       id="text817"><tspan
+         sodipodi:role="line"
+         id="tspan815"
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+    <text
+       xml:space="preserve"
+       style="font-style:normal;font-variant:normal;font-weight:normal;font-stretch:normal;font-size:10.58333302px;line-height:125%;font-family:'Latin Modern Math';-inkscape-font-specification:'Latin Modern Math';letter-spacing:0px;word-spacing:0px;fill:#000000;fill-opacity:1;stroke:none;stroke-width:0.26458332px;stroke-linecap:butt;stroke-linejoin:miter;stroke-opacity:1"
+       x="78.808037"
+       y="151.29018"
+       id="text825"><tspan
+         sodipodi:role="line"
+         id="tspan823"
+         x="78.808037"
+         y="151.29018"
+         style="font-style:italic;font-variant:normal;font-weight:normal;font-stretch:normal;font-family:FreeSerif;-inkscape-font-specification:'FreeSerif Italic';fill:#969696;fill-opacity:1;stroke-width:0.26458332px">f(x)</tspan></text>
+    <path
+       style="fill:none;fill-rule:evenodd;stroke:#969696;stroke-width:0.271;stroke-linecap:butt;stroke-linejoin:miter;stroke-miterlimit:4;stroke-dasharray:none;stroke-opacity:1"
+       d="m 78.040368,148.85072 h 17.36328"
+       id="path867"
+       inkscape:connector-curvature="0" />
+  </g>
+</svg>

Software/PC_Application/icons/math_enabled.svg

@@ -0,0 +1,79 @@
+<?xml version="1.0" encoding="UTF-8" standalone="no"?>
+<!-- Created with Inkscape (http://www.inkscape.org/) -->
+
+<svg
+   xmlns:dc="http://purl.org/dc/elements/1.1/"
+   xmlns:cc="http://creativecommons.org/ns#"
+   xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#"
+   xmlns:svg="http://www.w3.org/2000/svg"
+   xmlns="http://www.w3.org/2000/svg"
+   xmlns:sodipodi="http://sodipodi.sourceforge.net/DTD/sodipodi-0.dtd"
+   xmlns:inkscape="http://www.inkscape.org/namespaces/inkscape"
+   width="16.50322mm"
+   height="9.36625mm"
+   viewBox="0 0 16.50322 9.36625"
+   version="1.1"
+   id="svg8"
+   inkscape:version="0.92.3 (2405546, 2018-03-11)"
+   sodipodi:docname="math_enabled.svg">
+  <defs
+     id="defs2" />
+  <sodipodi:namedview
+     id="base"
+     pagecolor="#ffffff"
+     bordercolor="#666666"
+     borderopacity="1.0"
+     inkscape:pageopacity="0.0"
+     inkscape:pageshadow="2"
+     inkscape:zoom="11.2"
+     inkscape:cx="43.1742"
+     inkscape:cy="5.0657458"
+     inkscape:document-units="mm"
+     inkscape:current-layer="layer1"
+     showgrid="false"
+     inkscape:window-width="1853"
+     inkscape:window-height="1025"
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