Add ordinate computation and related functionality

Fix #125
Fix #126

Author: PierreRaybaut

CHANGELOG.md

@@ -15,6 +15,11 @@ See DataLab [roadmap page](https://datalab-platform.com/en/contributing/roadmap.
   * Added the "Select tool" to editor's toolbar, to allow the user to switch between the "Select" and "Draw" tools easily without having to use the plot toolbar on the top of the window
 * Signal processing features ("Processing" menu):
   * New "X-Y mode" feature: this feature simulates the behavior of the X-Y mode of an oscilloscope, i.e. it allows to plot one signal as a function of another signal (e.g. X as a function of Y)
+  * New abscissa and ordinate find features:
+    * "First abscissa at y=..." feature: this feature allows to find the first abscissa value of a signal at a given y value (e.g. the abscissa value of a signal at y=0)
+    * "Ordinate at x=..." feature: this feature allows to find the ordinate value of a signal at a given x value (e.g. the ordinate value of a signal at x=0)
+    * Each feature has its own dialog box, which allows to set the y or x value to be used for the search with a slider or a text box
+    * This closes [Issue #125](https://github.com./DataLab-Platform/DataLab/issues/125) and [Issue #126](https://github.com./DataLab-Platform/DataLab/issues/126)
 * Public API (local or remote):
   * Add `group_id` and `set_current` arguments to `add_signal`, `add_image` and `add_object` methods:
     * This concerns the `LocalProxy`, `AbstractCDLControl`, `RemoteClient`, `RemoteServer` and `CDLMainWindow` classes

cdl/algorithms/signal.py

@@ -569,6 +569,31 @@ def find_first_x_at_y_value(x: np.ndarray, y: np.ndarray, y_value: float) -> flo
     return np.nan  # not found
 
 
+def find_y_at_x_value(x: np.ndarray, y: np.ndarray, x_value: float) -> float:
+    """Find the y value at a given x value using linear interpolation.
+
+    Args:
+        x: Monotonic X data
+        y: Y data (may contain NaNs)
+        x_value: The x value to find the corresponding y value for
+
+    Returns:
+        The interpolated y value at the given x, or `nan` if not computable
+    """
+    if np.isnan(x_value):
+        return np.nan
+
+    # Filter out NaNs
+    valid = ~(np.isnan(x) | np.isnan(y))
+    x_valid = x[valid]
+    y_valid = y[valid]
+
+    if len(x_valid) == 0 or x_value < x_valid[0] or x_value > x_valid[-1]:
+        return np.nan
+
+    return float(np.interp(x_value, x_valid, y_valid))
+
+
 def find_x_at_value(x: np.ndarray, y: np.ndarray, value: float) -> np.ndarray:
     """Find the x values where the y value is the closest to the given value using
     linear interpolation to deduce the precise x value.

cdl/computation/signal.py

@@ -1611,6 +1611,30 @@ def compute_x_at_y(obj: SignalObj, p: FindAbscissaParam) -> ResultProperties:
     )
 
 
+class FindOrdinateParam(gds.DataSet):
+    """Parameter dataset for ordinate finding"""
+
+    x = gds.FloatItem(_("Abscissa"), default=0)
+
+
+def compute_y_at_x(obj: SignalObj, p: FindOrdinateParam) -> ResultProperties:
+    """
+    Compute the smallest y-value at a given x-value for a signal object.
+
+    Args:
+        obj: The signal object containing x and y data.
+        p: The parameter dataset for finding the ordinate.
+
+    Returns:
+         An object containing the y-value.
+    """
+    return calc_resultproperties(
+        f"y|x={p.x}",
+        obj,
+        {"y = %g {.yunit}": lambda xy: alg.find_y_at_x_value(xy[0], xy[1], p.x)},
+    )
+
+
 def compute_stats(obj: SignalObj) -> ResultProperties:
     """Compute statistics on a signal
 

cdl/core/gui/actionhandler.py

@@ -1036,6 +1036,13 @@ def cra_fit(title, fitdlgfunc, iconname, tip: str | None = None):
                     "(linear interpolation)"
                 ),
             )
+            self.new_action(
+                _("Ordinate at x=..."),
+                triggered=self.panel.processor.compute_y_at_x,
+                tip=_(
+                    "Compute the ordinate at a given x value " "(linear interpolation)"
+                ),
+            )
             self.new_action(
                 _("Peak detection"),
                 separator=True,

cdl/core/gui/processor/signal.py

@@ -781,6 +781,23 @@ def compute_x_at_y(
                 return
         return self.compute_10(cps.compute_x_at_y, param)
 
+    @qt_try_except()
+    def compute_y_at_x(
+        self, param: cps.FindOrdinateParam | None = None
+    ) -> dict[str, ResultProperties]:
+        """Compute y at x with :py:func:`cdl.computation.signal.compute_y_at_x`."""
+        if param is None:
+            obj = self.panel.objview.get_sel_objects(include_groups=True)[0]
+            dlg = signalcursor.SignalCursorDialog(
+                obj, cursor_orientation="vertical", parent=self.panel.parent()
+            )
+            if exec_dialog(dlg):
+                param = cps.FindOrdinateParam()
+                param.x = dlg.get_x_value()
+            else:
+                return
+        return self.compute_10(cps.compute_y_at_x, param)
+
     @qt_try_except()
     def compute_sampling_rate_period(self) -> dict[str, ResultProperties]:
         """Compute sampling rate and period (mean and std)

cdl/locale/fr/LC_MESSAGES/cdl.po

@@ -4,7 +4,7 @@
 msgid ""
 msgstr ""
 "Project-Id-Version: PACKAGE VERSION\n"
-"POT-Creation-Date: 2025-04-13 10:06+0200\n"
+"POT-Creation-Date: 2025-04-13 11:34+0200\n"
 "PO-Revision-Date: YEAR-MO-DA HO:MI+ZONE\n"
 "Last-Translator: FULL NAME <EMAIL@ADDRESS>\n"
 "Language-Team: LANGUAGE <[email protected]>\n"
@@ -793,6 +793,9 @@ msgstr ""
 msgid "Ordinate"
 msgstr "Coordonnées"
 
+msgid "Abscissa"
+msgstr "Abscisse"
+
 msgid "Full scale"
 msgstr "Pleine échelle"
 
@@ -1214,6 +1217,12 @@ msgid "Compute the first abscissa at a given y value (linear interpolation)"
 msgstr ""
 "Calcule la première abscisse à une valeur y donnée (interpolation linéaire)"
 
+msgid "Ordinate at x=..."
+msgstr "Ordonnée à x=..."
+
+msgid "Compute the ordinate at a given x value (linear interpolation)"
+msgstr "Calcule l'ordonnée à une valeur x donnée (interpolation linéaire)"
+
 msgid "Peak detection"
 msgstr "Détection de pics"
 
@@ -2279,9 +2288,6 @@ msgstr "LMH"
 msgid "FW"
 msgstr "LH"
 
-msgid "Find abscissa"
-msgstr "Trouver l'abscisse"
-
 msgid "Bandwidth"
 msgstr "Bande passante"
 
@@ -3362,6 +3368,17 @@ msgstr "Sélectionner la valeur X avec le curseur"
 msgid "Select Y value with cursor"
 msgstr "Sélectionner la valeur Y avec le curseur"
 
+msgid "Apply"
+msgstr ""
+
+#, fuzzy
+msgid "Apply cursor position"
+msgstr "Position de la barre d'outils des graphiques"
+
+#, fuzzy
+msgid "Cursor position"
+msgstr "Position du centre"
+
 msgid "Minimum distance:"
 msgstr "Distance minimale :"
 

cdl/tests/features/signals/analysis_unit_test.py

@@ -84,10 +84,25 @@ def test_signal_x_at_y() -> None:
     check_scalar_result("x|y=0.5", df["x"][0], 0.0)
 
 
+@pytest.mark.validation
+def test_signal_y_at_x() -> None:
+    """Validation test for the ordinate finding computation."""
+    newparam = cdl.obj.new_signal_param(
+        stype=cdl.obj.SignalTypes.TRIANGLE, xmin=0.0, xmax=10.0, size=101
+    )
+    obj = cdl.obj.create_signal_from_param(newparam)
+    if obj is None:
+        raise ValueError("Failed to create test signal")
+    param = cps.FindOrdinateParam.create(x=2.5)
+    df = cps.compute_y_at_x(obj, param).to_dataframe()
+    check_scalar_result("y|x=0.5", df["y"][0], 1.0)
+
+
 if __name__ == "__main__":
     test_signal_bandwidth_3db()
     test_dynamic_parameters()
     test_signal_sampling_rate_period()
     test_signal_contrast()
     test_signal_x_at_minmax()
     test_signal_x_at_y()
+    test_signal_y_at_x()

cdl/tests/features/signals/select_xy_cursor_unit_test.py

@@ -10,6 +10,7 @@
 from typing import Literal
 
 import numpy as np
+import pytest
 from guidata.qthelpers import exec_dialog, qt_app_context
 
 from cdl.algorithms.signal import find_first_x_at_y_value
@@ -18,10 +19,11 @@
 from cdl.widgets.signalcursor import SignalCursorDialog
 
 
+@pytest.mark.parametrize("cursor_orientation", ["horizontal", "vertical"])
 def test_signal_cursor_selection(
     cursor_orientation: Literal["horizontal", "vertical"],
 ) -> None:
-    """Signal cursor selection unit test."""
+    """Parametrized signal cursor selection unit test."""
     sig = create_paracetamol_signal()
     with qt_app_context():
         dlg = SignalCursorDialog(signal=sig, cursor_orientation=cursor_orientation)

doc/locale/fr/LC_MESSAGES/contributing/changelog.po

@@ -7,7 +7,7 @@ msgid ""
 msgstr ""
 "Project-Id-Version: DataLab \n"
 "Report-Msgid-Bugs-To: \n"
-"POT-Creation-Date: 2025-04-08 11:05+0200\n"
+"POT-Creation-Date: 2025-04-13 11:52+0200\n"
 "PO-Revision-Date: YEAR-MO-DA HO:MI+ZONE\n"
 "Last-Translator: FULL NAME <EMAIL@ADDRESS>\n"
 "Language: fr\n"
@@ -57,6 +57,21 @@ msgstr "Fonctionnalités de traitement du signal (menu \"Traitement\") :"
 msgid "New \"X-Y mode\" feature: this feature simulates the behavior of the X-Y mode of an oscilloscope, i.e. it allows to plot one signal as a function of another signal (e.g. X as a function of Y)"
 msgstr "Nouvelle fonctionnalité \"Mode X-Y\" : cette fonctionnalité simule le comportement du mode X-Y d'un oscilloscope, c'est-à-dire qu'elle permet de tracer un signal en fonction d'un autre signal (par exemple X en fonction de Y)"
 
+msgid "New abscissa and ordinate find features:"
+msgstr "Nouvelles fonctionnalités de recherche d'abscisse et d'ordonnée :"
+
+msgid "\"First abscissa at y=...\" feature: this feature allows to find the first abscissa value of a signal at a given y value (e.g. the abscissa value of a signal at y=0)"
+msgstr "Fonctionnalité \"Abscisse à y=...\" : cette fonctionnalité permet de trouver la première valeur d'abscisse d'un signal à une valeur y donnée (par exemple, la valeur d'abscisse d'un signal à y=0)"
+
+msgid "\"Ordinate at x=...\" feature: this feature allows to find the ordinate value of a signal at a given x value (e.g. the ordinate value of a signal at x=0)"
+msgstr "Fonctionnalité \"Ordonnée à x=...\" : cette fonctionnalité permet de trouver la valeur d'ordonnée d'un signal à une valeur x donnée (par exemple, la valeur d'ordonnée d'un signal à x=0)"
+
+msgid "Each feature has its own dialog box, which allows to set the y or x value to be used for the search with a slider or a text box"
+msgstr "Chaque fonctionnalité a sa propre boîte de dialogue, qui permet de définir la valeur y ou x à utiliser pour la recherche avec un curseur ou une zone de texte"
+
+msgid "This closes [Issue #125](https://github.com./DataLab-Platform/DataLab/issues/125) and [Issue #126](https://github.com./DataLab-Platform/DataLab/issues/126)"
+msgstr "Ceci clotûre les tickets [Issue #125](https://github.com./DataLab-Platform/DataLab/issues/125) et [Issue #126](https://github.com./DataLab-Platform/DataLab/issues/126)"
+
 msgid "Public API (local or remote):"
 msgstr "API publique (locale ou distante) :"
 
@@ -129,9 +144,6 @@ msgstr "Correction de l'[Issue #165](https://github.com./DataLab-Platform/DataLab
 msgid "DataLab Version 0.19.0"
 msgstr "DataLab Version 0.19.0"
 
-msgid "💥 New features and enhancements:"
-msgstr "💥 Nouvelles fonctionnalités et améliorations :"
-
 msgid "Image operation features (\"Operations\" menu):"
 msgstr "Fonctionnalités d'opération sur les images (menu \"Opérations\") :"
 
@@ -141,9 +153,6 @@ msgstr "Renommage du sous-menu \"Rotation\" en \"Symétrie ou rotation\""
 msgid "New \"Flip diagonally\" feature"
 msgstr "Nouvelle fonctionnalité \"Symétrie diagonale\""
 
-msgid "Signal processing features (\"Processing\" menu):"
-msgstr "Fonctionnalités de traitement du signal (menu \"Traitement\") :"
-
 msgid "New \"Convert to Cartesian coordinates\" feature"
 msgstr "Nouvelle fonctionnalité \"Convertir en coordonnées cartésiennes\""
 
@@ -183,9 +192,6 @@ msgstr "Ajout de la méthode `compute_inverse` pour les processeurs d'image et d
 msgid "This closes [Issue #143](https://github.com./DataLab-Platform/DataLab/issues/143) - New feature: `1/x` for signals and images"
 msgstr "Ceci corrige l'[Issue #143](https://github.com./DataLab-Platform/DataLab/issues/143) - Nouvelle fonctionnalité : `1/x` pour les signaux et les images"
 
-msgid "Public API (local or remote):"
-msgstr "API publique (locale ou distante) :"
-
 msgid "Add `add_group` method with `title` and `select` arguments to create a new group in a data panel (e.g. Signal or Image panel) and eventually select it after creation:"
 msgstr "Ajout de la méthode `add_group` avec les arguments `title` et `select` pour créer un nouveau groupe dans un panneau de données (par exemple, panneau Signal ou Image) et éventuellement le sélectionner après sa création :"
 
@@ -258,9 +264,6 @@ msgstr "La ROI polygonale n'est pas encore prise en charge"
 msgid "This closes [Issue #145](https://github.com./DataLab-Platform/DataLab/issues/145) - ROI editor: add manual input of the coordinates"
 msgstr "Ceci clotûre le ticket [Issue #145](https://github.com./DataLab-Platform/DataLab/issues/145) - Éditeur de ROI : ajouter la saisie manuelle des coordonnées"
 
-msgid "🛠️ Bug fixes:"
-msgstr "🛠️ Corrections de bugs :"
-
 msgid "Fixed [Issue #141](https://github.com./DataLab-Platform/DataLab/issues/141) - Image analysis: mask `nan` values when computing statistics, for example"
 msgstr "Correction de l'[Issue #141](https://github.com./DataLab-Platform/DataLab/issues/141) - Analyse d'image : masque des valeurs `nan` lors du calcul des statistiques, par exemple"