fixe fft from pyqtgraph

wrap _fourierTransform to fixe pyqtgraph/issues/3018 before patch pyqtgraph/pull/3070

autolab/core/gui/GUI_utilities.py

@@ -15,8 +15,24 @@
 
 from ..config import get_GUI_config
 
+
+# Fixes pyqtgraph/issues/3018 for pg<=0.13.7 (before pyqtgraph/pull/3070)
+from pyqtgraph.graphicsItems.PlotDataItem import PlotDataItem
+
+if hasattr(PlotDataItem, '_fourierTransform'):
+
+    _fourierTransform_bugged = PlotDataItem._fourierTransform
+
+    def _fourierTransform_fixed(self, x, y):
+        if len(x) == 1: return np.array([0]), abs(y)
+        return _fourierTransform_bugged(self, x, y)
+
+    PlotDataItem._fourierTransform = _fourierTransform_fixed
+
+
 ONCE = False
 
+
 def get_font_size() -> int:
     GUI_config = get_GUI_config()
     if GUI_config['font_size'] != 'default':
@@ -189,6 +205,7 @@ def update_img(self, x, y, z):
         self.img = img
         self.ax.addItem(self.img)
 
+
 def pyqtgraph_fig_ax() -> Tuple[MyGraphicsLayoutWidget, pg.PlotItem]:
     """ Return a formated fig and ax pyqtgraph for a basic plot """
     fig = MyGraphicsLayoutWidget()

autolab/core/gui/scanning/figure.py

@@ -632,7 +632,6 @@ def reloadData(self):
                         alpha = (true_nbtraces - (len(data) - 1 - i)) / true_nbtraces
 
                     # Plot
-                    # OPTIMIZE: known issue but from pyqtgraph, error if use FFT on one point
                     # careful, now that can filter data, need .values to avoid pyqtgraph bug
                     curve = self.ax.plot(x.values, y.values, symbol='x',
                                          symbolPen=color, symbolSize=10,