Fix: Add xaxis.range[0]/[1] If Not Exist (#342)

* Fix: Add xaxis.range[0]/[1] If Not Exist #335

* 🔍 adding test + some more docs

---------

Co-authored-by: yzhaoinuw <[email protected]>

Author: jonasvdd

plotly_resampler/figure_resampler/figure_resampler_interface.py

@@ -1299,6 +1299,25 @@ def _construct_update_data(
             # 1. Base case - there is an x-range specified in the front-end
             start_matches = self._re_matches(re.compile(r"xaxis\d*.range\[0]"), cl_k)
             stop_matches = self._re_matches(re.compile(r"xaxis\d*.range\[1]"), cl_k)
+
+            # related issue: https://github.com/predict-idlab/plotly-resampler/pull/336
+            # When the user sets x range via update_xaxes and the number of points in
+            # data exceeds the default_n_shown_samples, then after resetting the axes
+            # the relayout may only have "xaxis.range", instead of "xaxis.range[0]" and
+            # "xaxis.range[1]". If this happens, we need to manually add "xaxis.range[0]"
+            # and "xaxis.range[1]", otherwise resetting axes wouldn't work.
+            if not (start_matches and stop_matches):
+                range_matches = self._re_matches(re.compile(r"xaxis\d*.range"), cl_k)
+                for range_match in range_matches:
+                    x_range = relayout_data[range_match]
+                    start, stop = x_range
+                    start_match = range_match + "[0]"
+                    stop_match = range_match + "[1]"
+                    relayout_data[start_match] = start
+                    relayout_data[stop_match] = stop
+                    start_matches.append(start_match)
+                    stop_matches.append(stop_match)
+                    del x_range, start, stop, start_match, stop_match
             if start_matches and stop_matches:  # when both are not empty
                 for t_start_key, t_stop_key in zip(start_matches, stop_matches):
                     # Check if the xaxis<NUMB> part of xaxis<NUMB>.[0-1] matches

tests/test_figure_resampler.py

@@ -1984,3 +1984,43 @@ def test_hf_marker_size_plotly_args():
         (np.abs(update_trace["y"]) / np.max(np.abs(y))),
         rtol=1e-3,
     )
+
+
+@pytest.mark.parametrize("shared_xaxes", [False, True])
+def test_manual_range_def(shared_xaxes):
+    # related issue: https://github.com/predict-idlab/plotly-resampler/pull/336
+    time = 1000
+    N = 4001  # number of points in the subplot exceeds default_n_shown_samples
+    x = np.linspace(0.0, time, N, endpoint=False)
+    y = np.cos(1 / 2 * np.pi + 2 / 50 * np.pi * x)
+
+    # Create a subplot with two rows (non shared xaxes)
+    fig = FigureResampler(make_subplots(rows=2, cols=1, shared_xaxes=shared_xaxes))
+    fig.add_trace(
+        go.Scattergl(line=dict(width=1), marker=dict(size=2, color="blue")),
+        hf_x=x,
+        hf_y=y,
+        row=1,
+        col=1,
+    )
+    fig.add_trace(go.Scattergl(), hf_x=x, hf_y=-y, row=2, col=1)
+
+    fig.update_xaxes(
+        range=[0, np.ceil(x[-1])],  # set the x range of the subplot
+        row=1,
+        col=1,
+    )
+
+    fig.update_xaxes(
+        range=[0, np.ceil(x[-1])],  # set the x range of the subplot
+        row=2,
+        col=1,
+    )
+
+    # Before this fix, a noUpdate was returned
+    ud = fig._construct_update_data({"xaxis.range": [0, 10]})
+    assert isinstance(ud, list) and len(ud) == 2
+    ud = fig._construct_update_data({"xaxis2.range": [0, 10]})
+    assert isinstance(ud, list) and len(ud) == 2
+    ud = fig._construct_update_data({"xaxis2.range": [2, 10], "xaxis.range": [5, 100]})
+    assert isinstance(ud, list) and len(ud) == 3