Merge pull request #2007 from HEXRD/wppf-diff

WPPF difference curve update.

Author: saransh13

hexrdgui/calibration/wppf_options_dialog.py

@@ -341,12 +341,13 @@ def write_data(self, filename: str | Path) -> None:
 
         # Prepare the data to write out
         two_theta, intensity = obj.spectrum_sim.x, obj.spectrum_sim.y
+        weights = obj.weights.y
         bkg = obj.background.y
         data = {
             'two_theta': two_theta,
             'intensity': intensity,
             'lineout_intensity': lineout_intensity,
-            'difference_curve': intensity - lineout_intensity,
+            'difference_curve': (intensity - lineout_intensity) * np.sqrt(weights),
             'background': bkg,
         }
         if obj.amorphous_model is not None:

hexrdgui/image_canvas.py

@@ -2020,22 +2020,19 @@ def update_wppf_plot(self) -> None:
             if is_percent:
                 # Express `y` as a percentage instead
                 y *= 100 / last_lineout[1].filled(np.nan)
+            else:
+                denom = np.sqrt(last_lineout[1].filled(np.nan))
+                denom[denom == 0] = np.nan
+                y /= denom
 
             (self.wppf_difference_plot,) = diff_axis.plot(x, y, **style)
 
             # Rescale
             diff_axis.relim()
             diff_axis.autoscale_view(scalex=False)
 
-            if is_percent:
-                # Force an auto-scale
-                diff_axis.autoscale(enable=True, axis='y')
-            else:
-                # When the difference plot resets, always set it to be
-                # initially the same y range as the azimuthal.
-                new_ymin = min(diff_axis.get_ylim()[0], -axis.get_ylim()[1])
-                new_ymax = max(diff_axis.get_ylim()[1], axis.get_ylim()[1])
-                diff_axis.set_ylim((new_ymin, new_ymax))
+            # Force an auto-scale
+            diff_axis.autoscale(enable=True, axis='y')
 
         # Update the difference label even if there's no data
         self.update_wppf_difference_labels()
@@ -2048,7 +2045,7 @@ def update_wppf_difference_labels(self) -> None:
         if HexrdConfig().show_wppf_difference_as_percent:
             label = r'WPPF Diff (%)'
         else:
-            label = r'WPPF Diff'
+            label = r'$\Delta$I/$\sigma$(I)'
 
         axis.set_ylabel(label, **self.label_kwargs_polar_y)