various chart window updates and improvements

- charts are reset if the thermo style changes
- charts are reset if the timestep is reset (to a lower value)
- charts are not updated if thermo data is not valid (e.g. during setup)
- use integer format for Steps on the x-axis

tools/lammps-gui/chartviewer.cpp

@@ -49,6 +49,31 @@ ChartWindow::ChartWindow(const QString &_filename, QWidget *parent) :
     resize(settings.value("chartx", 500).toInt(), settings.value("charty", 320).toInt());
 }
 
+int ChartWindow::get_step() const
+{
+    if (charts.size() > 0) {
+        auto *v = charts[0];
+        return (int)v->get_step(v->get_count()-1);
+    } else {
+        return -1;
+    }
+}
+
+void ChartWindow::reset_charts()
+{
+    while (layout()->count() > 1) {
+        auto *item = layout()->takeAt(1);
+        if (item) {
+            layout()->removeItem(item);
+            delete item->widget();
+            delete item;
+        }
+    }
+    charts.clear();
+    columns->clear();
+    active_chart = 0;
+}
+
 void ChartWindow::add_chart(const QString &title, int index)
 {
     auto *chart = new ChartViewer(title, index);
@@ -182,6 +207,7 @@ ChartViewer::ChartViewer(const QString &title, int _index, QWidget *parent) :
     series->attachAxis(yaxis);
     xaxis->setTitleText("Time step");
     xaxis->setTickCount(5);
+    xaxis->setLabelFormat("%d");
     yaxis->setTickCount(5);
     xaxis->setMinorTickCount(5);
     yaxis->setMinorTickCount(5);

tools/lammps-gui/chartviewer.h

@@ -31,7 +31,13 @@ class ChartWindow : public QWidget {
 public:
     ChartWindow(const QString &filename, QWidget *parent = nullptr);
 
-    bool has_charts() const { return !charts.isEmpty(); }
+    int num_charts() const { return charts.size(); }
+    bool has_title(const QString &title, int index) const
+    {
+        return (columns->itemText(index) == title);
+    }
+    int get_step() const;
+    void reset_charts();
     void add_chart(const QString &title, int index);
     void add_data(int step, double data, int index);
 

tools/lammps-gui/lammpsgui.cpp

@@ -558,7 +558,11 @@ void LammpsGui::logupdate()
 
     // extract cached thermo data
     if (chartwindow) {
-        void *ptr = lammps.last_thermo("step", 0);
+        // thermo data is not yet valid during setup
+        void *ptr = lammps.last_thermo("setup", 0);
+        if (ptr && *(int *)ptr) return;
+
+        ptr = lammps.last_thermo("step", 0);
         if (ptr) {
             int step = 0;
             if (lammps.extract_setting("bigint") == 4)
@@ -566,7 +570,29 @@ void LammpsGui::logupdate()
             else
                 step = (int)*(int64_t *)ptr;
             int ncols = *(int *)lammps.last_thermo("num", 0);
-            if (!chartwindow->has_charts()) {
+
+            // check if the column assignment has changed
+            // if yes, delete charts and start over
+            if (chartwindow->num_charts() > 0) {
+                int count     = 0;
+                bool do_reset = false;
+                if (step < chartwindow->get_step()) do_reset = true;
+                for (int i = 0, idx = 0; i < ncols; ++i) {
+                    QString label = (const char *)lammps.last_thermo("keyword", i);
+                    // no need to store the timestep column
+                    if (label == "Step") continue;
+                    if (!chartwindow->has_title(label, idx)) {
+                        do_reset = true;
+                    } else {
+                        ++count;
+                    }
+                    ++idx;
+                }
+                if (chartwindow->num_charts() != count) do_reset = true;
+                if (do_reset) chartwindow->reset_charts();
+            }
+
+            if (chartwindow->num_charts() == 0) {
                 for (int i = 0; i < ncols; ++i) {
                     QString label = (const char *)lammps.last_thermo("keyword", i);
                     // no need to store the timestep column
@@ -622,7 +648,7 @@ void LammpsGui::run_done()
                 step = (int)*(int64_t *)ptr;
             int ncols = *(int *)lammps.last_thermo("num", 0);
             for (int i = 0; i < ncols; ++i) {
-                if (!chartwindow->has_charts()) {
+                if (chartwindow->num_charts() == 0) {
                     QString label = (const char *)lammps.last_thermo("keyword", i);
                     // no need to store the timestep column
                     if (label == "Step") continue;