remove widgest to set start and stop values for histogram bins

Author: p-j-smith

src/napari_matplotlib/histogram.py

@@ -7,9 +7,7 @@
 from napari.layers import Image
 from napari.layers._multiscale_data import MultiScaleData
 from qtpy.QtWidgets import (
-    QAbstractSpinBox,
     QComboBox,
-    QDoubleSpinBox,
     QFormLayout,
     QGroupBox,
     QLabel,
@@ -30,41 +28,29 @@
 def _get_bins(
     data: npt.NDArray[Any],
     num_bins: int = 100,
-    start: int | float | None = None,
-    stop: int | float | None = None,
 ) -> npt.NDArray[Any]:
     """Create evenly spaced bins with a given interval.
 
-    If `start` or `stop` are `None`, they will be set based on the minimum
-    and maximum values, respectively, of the data.
-
     Parameters
     ----------
     data : napari.layers.Layer.data
         Napari layer data.
     num_bins : integer, optional
-        Number of evenly-spaced bins to create.
-    start : integer or real, optional
-        Start bin edge. Defaults to the minimum value of `data`.
-    stop : integer or real, optional
-        Stop bin edge. Defaults to the maximum value of `data`.
+        Number of evenly-spaced bins to create. Defaults to 100.
 
     Returns
     -------
     bin_edges : numpy.ndarray
         Array of evenly spaced bin edges.
     """
-    start = np.min(data) if start is None else start
-    stop = np.max(data) if stop is None else stop
-
     if data.dtype.kind in {"i", "u"}:
         # Make sure integer data types have integer sized bins
-        step = np.ceil((stop - start) / num_bins)
-        return np.arange(start, stop + step, step)
+        step = np.ceil(np.ptp(data) / num_bins)
+        return np.arange(np.min(data), np.max(data) + step, step)
     else:
         # For other data types we can use exactly `num_bins` bins
         # (and `num_bins` + 1 bin edges)
-        return np.linspace(start, stop, num_bins + 1)
+        return np.linspace(np.min(data), np.max(data), num_bins + 1)
 
 
 class HistogramWidget(SingleAxesWidget):
@@ -82,53 +68,28 @@ def __init__(
     ):
         super().__init__(napari_viewer, parent=parent)
 
-        # Create widgets for setting bin parameters
-        bins_start = QDoubleSpinBox()
-        bins_start.setStepType(QAbstractSpinBox.AdaptiveDecimalStepType)
-        bins_start.setRange(-1e10, 1e10)
-        bins_start.setValue(0)
-        bins_start.setWrapping(False)
-        bins_start.setKeyboardTracking(False)
-        bins_start.setDecimals(2)
-
-        bins_stop = QDoubleSpinBox()
-        bins_stop.setStepType(QAbstractSpinBox.AdaptiveDecimalStepType)
-        bins_stop.setRange(-1e10, 1e10)
-        bins_stop.setValue(100)
-        bins_start.setWrapping(False)
-        bins_stop.setKeyboardTracking(False)
-        bins_stop.setDecimals(2)
-
-        bins_num = QSpinBox()
-        bins_num.setRange(1, 100_000)
-        bins_num.setValue(101)
-        bins_num.setWrapping(False)
-        bins_num.setKeyboardTracking(False)
+        num_bins_widget = QSpinBox()
+        num_bins_widget.setRange(1, 100_000)
+        num_bins_widget.setValue(101)
+        num_bins_widget.setWrapping(False)
+        num_bins_widget.setKeyboardTracking(False)
 
         # Set bins widget layout
         bins_selection_layout = QFormLayout()
-        bins_selection_layout.addRow("start", bins_start)
-        bins_selection_layout.addRow("stop", bins_stop)
-        bins_selection_layout.addRow("num", bins_num)
+        bins_selection_layout.addRow("num bins", num_bins_widget)
 
         # Group the widgets and add to main layout
-        bins_widget_group = QGroupBox("Bins")
-        bins_widget_group_layout = QVBoxLayout()
-        bins_widget_group_layout.addLayout(bins_selection_layout)
-        bins_widget_group.setLayout(bins_widget_group_layout)
-        self.layout().addWidget(bins_widget_group)
+        params_widget_group = QGroupBox("Params")
+        params_widget_group_layout = QVBoxLayout()
+        params_widget_group_layout.addLayout(bins_selection_layout)
+        params_widget_group.setLayout(params_widget_group_layout)
+        self.layout().addWidget(params_widget_group)
 
         # Add callbacks
-        bins_start.valueChanged.connect(self._draw)
-        bins_stop.valueChanged.connect(self._draw)
-        bins_num.valueChanged.connect(self._draw)
+        num_bins_widget.valueChanged.connect(self._draw)
 
         # Store widgets for later usage
-        self._bin_widgets = {
-            "start": bins_start,
-            "stop": bins_stop,
-            "num": bins_num,
-        }
+        self.num_bins_widget = num_bins_widget
 
         self._update_layers(None)
         self.viewer.events.theme.connect(self._on_napari_theme_changed)
@@ -144,27 +105,9 @@ def on_update_layers(self) -> None:
         if not self.layers:
             return
 
-        # Reset the bin start, stop and step values based on new layer data
+        # Reset the num bins based on new layer data
         layer_data = self._get_layer_data(self.layers[0])
-        self.autoset_widget_bins(data=layer_data)
-
-        # Only allow integer bins for integer data
-        # And only allow values greater than 0 for unsigned integers
-        n_decimals = 0 if np.issubdtype(layer_data.dtype, np.integer) else 2
-        is_unsigned = layer_data.dtype.kind == "u"
-        minimum_value = 0 if is_unsigned else -1e10
-
-        # Disable callbacks whilst widget values might change
-        for widget in self._bin_widgets.values():
-            widget.blockSignals(True)
-
-        self._bin_widgets["start"].setDecimals(n_decimals)
-        self._bin_widgets["stop"].setDecimals(n_decimals)
-        self._bin_widgets["start"].setMinimum(minimum_value)
-        self._bin_widgets["stop"].setMinimum(minimum_value)
-
-        for widget in self._bin_widgets.values():
-            widget.blockSignals(False)
+        self._set_widget_nums_bins(data=layer_data)
 
     def _update_contrast_lims(self) -> None:
         for lim, line in zip(
@@ -174,50 +117,10 @@ def _update_contrast_lims(self) -> None:
 
         self.figure.canvas.draw()
 
-    def autoset_widget_bins(self, data: npt.NDArray[Any]) -> None:
-        """Update widgets with bins determined from the image data"""
+    def _set_widget_nums_bins(self, data: npt.NDArray[Any]) -> None:
+        """Update num_bins widget with bins determined from the image data"""
         bins = _get_bins(data)
-
-        # Disable callbacks whilst setting widget values
-        for widget in self._bin_widgets.values():
-            widget.blockSignals(True)
-
-        self.bins_start = bins[0]
-        self.bins_stop = bins[-1]
-        self.bins_num = bins.size - 1
-
-        for widget in self._bin_widgets.values():
-            widget.blockSignals(False)
-
-    @property
-    def bins_start(self) -> float:
-        """Minimum bin edge"""
-        return self._bin_widgets["start"].value()
-
-    @bins_start.setter
-    def bins_start(self, start: int | float) -> None:
-        """Set the minimum bin edge"""
-        self._bin_widgets["start"].setValue(start)
-
-    @property
-    def bins_stop(self) -> float:
-        """Maximum bin edge"""
-        return self._bin_widgets["stop"].value()
-
-    @bins_stop.setter
-    def bins_stop(self, stop: int | float) -> None:
-        """Set the maximum bin edge"""
-        self._bin_widgets["stop"].setValue(stop)
-
-    @property
-    def bins_num(self) -> int:
-        """Number of bins to use"""
-        return self._bin_widgets["num"].value()
-
-    @bins_num.setter
-    def bins_num(self, num: int) -> None:
-        """Set the number of bins to use"""
-        self._bin_widgets["num"].setValue(num)
+        self.num_bins_widget.setValue(bins.size - 1)
 
     def _get_layer_data(self, layer: napari.layers.Layer) -> npt.NDArray[Any]:
         """Get the data associated with a given layer"""
@@ -248,9 +151,7 @@ def draw(self) -> None:
         # whole cube into memory.
         bins = _get_bins(
             data,
-            num_bins=self.bins_num,
-            start=self.bins_start,
-            stop=self.bins_stop,
+            num_bins=self.num_bins_widget.value(),
         )
 
         if layer.rgb:

src/napari_matplotlib/tests/baseline/test_histogram_2D_bins.png

@@ -17,9 +17,7 @@ def test_histogram_2D_bins(make_napari_viewer, astronaut_data):
     viewer.add_image(astronaut_data[0], **astronaut_data[1])
     widget = HistogramWidget(viewer)
     viewer.window.add_dock_widget(widget)
-    widget.bins_start = 0
-    widget.bins_stop = 350
-    widget.bins_num = 35
+    widget.num_bins_widget.setValue(25)
     fig = widget.figure
     # Need to return a copy, as original figure is too eagerley garbage
     # collected by the widget