API/UI to reestimate model parameter initial values

CHANGES.rst

@@ -16,6 +16,9 @@ New Features
 
 - Linear1D model component now estimates slope and intercept. [#1947]
 
+- Model fitting: API and UI to re-estimate model parameters based on current data/subset selection.
+  [#1952]
+
 Cubeviz
 ^^^^^^^
 

jdaviz/components/tooltip.vue

@@ -75,6 +75,8 @@ const tooltips = {
   'plugin-plot-options-mixed-state': 'Current values are mixed, click to sync at shown value',
   'plugin-model-fitting-add-model': 'Create model component',
   'plugin-model-fitting-param-fixed': 'Check the box to freeze parameter value',
+  'plugin-model-fitting-reestimate-all': 'Re-estimate initial values based on the current data/subset selection for all free parameters',
+  'plugin-model-fitting-reestimate': 'Re-estimate initial values based on the current data/subset selection for all free parameters in this component',
   'plugin-unit-conversion-apply': 'Apply unit conversion',
   'plugin-line-lists-load': 'Load list into "Loaded Lines" section of plugin',
   'plugin-line-lists-plot-all-in-list': 'Plot all lines in this list',

jdaviz/configs/default/plugins/model_fitting/model_fitting.py

@@ -59,6 +59,7 @@ class ModelFitting(PluginTemplateMixin, DatasetSelectMixin,
     * :meth:`model_components`
     * :meth:`get_model_component`
     * :meth:`set_model_component`
+    * :meth:`reestimate_model_parameters`
     * ``equation`` (:class:`~jdaviz.core.template_mixin.AutoTextField`)
     * ``cube_fit``
       Only exposed for Cubeviz.  Whether to fit the model to the cube instead of to the
@@ -161,7 +162,7 @@ def user_api(self):
             expose += ['spatial_subset']
         expose += ['spectral_subset', 'model_component', 'poly_order', 'model_component_label',
                    'model_components', 'create_model_component', 'remove_model_component',
-                   'get_model_component', 'set_model_component',
+                   'get_model_component', 'set_model_component', 'reestimate_model_parameters',
                    'equation', 'add_results', 'residuals_calculate', 'residuals']
         if self.config == "cubeviz":
             expose += ['cube_fit']
@@ -433,6 +434,13 @@ def create_model_component(self, model_component=None, model_component_label=Non
         if comp_label in [cm['id'] for cm in self.component_models]:
             raise ValueError(f"model component label '{comp_label}' already in use")
 
+        new_model = self._initialize_model_component(model_comp, comp_label, poly_order=poly_order)
+        self.component_models = self.component_models + [new_model]
+        # update the default label (likely adding the suffix)
+        self._update_comp_label_default()
+        self._update_model_equation_default()
+
+    def _initialize_model_component(self, model_comp, comp_label, poly_order=None):
         new_model = {"id": comp_label, "model_type": model_comp,
                      "parameters": [], "model_kwargs": {}}
         model_cls = MODELS[model_comp]
@@ -486,10 +494,7 @@ def create_model_component(self, model_component=None, model_component_label=Non
         self._initialized_models[comp_label] = initialized_model
 
         new_model["Initialized"] = True
-        self.component_models = self.component_models + [new_model]
-        # update the default label (likely adding the suffix)
-        self._update_comp_label_default()
-        self._update_model_equation_default()
+        return new_model
 
     def remove_model_component(self, model_component_label):
         """
@@ -581,6 +586,52 @@ def set_model_component(self, model_component_label, parameter, value=None, fixe
 
         return parameter
 
+    def vue_reestimate_model_parameters(self, model_component_label=None, **kwargs):
+        self.reestimate_model_parameters(model_component_label=model_component_label)
+
+    def reestimate_model_parameters(self, model_component_label=None):
+        """
+        Re-estimate all free parameters in a given model component given the currently selected
+        data and subset selections.
+
+        Parameters
+        ----------
+        model_component_label : str or None.
+            The label given to the existing model component.  If None, will iterate over all model
+            components.
+        """
+        if model_component_label is None:
+            ret = []
+            for model_comp in self.component_models:
+                ret.append(self.reestimate_model_parameters(model_comp["id"]))
+            return ret
+
+        try:
+            model_index, model_comp = [(i, x) for i, x in enumerate(self.component_models)
+                                       if x["id"] == model_component_label][0]
+        except IndexError:
+            raise ValueError(f"'{model_component_label}' is not a label of an existing model component")  # noqa
+
+        # store user-fixed parameters so we can revert after re-initializing
+        fixed_params = {p['name']: p for p in model_comp['parameters'] if p['fixed']}
+
+        new_model = self._initialize_model_component(model_comp['model_type'],
+                                                     model_component_label,
+                                                     poly_order=model_comp['model_kwargs'].get('degree', None))  # noqa
+
+        # revert fixed parameters to user-value
+        new_model['parameters'] = [fixed_params.get(p['name'], p) for p in new_model['parameters']]
+
+        # reset traitlet so vue picks up on changes by adding (and then removing) an empty entry,
+        # this avoids resetting the open state of the accordion in the UI.
+        component_models = self.component_models
+        component_models[model_index] = new_model
+        self.component_models = self.component_models + [{}]
+        self.component_models = self.component_models[:-1]
+
+        # return user-friendly info on revised model
+        return self.get_model_component(model_component_label)
+
     @property
     def model_components(self):
         """

jdaviz/configs/default/plugins/model_fitting/model_fitting.vue

@@ -81,6 +81,22 @@
 
     <div v-if="component_models.length">
       <j-plugin-section-header>Model Parameters</j-plugin-section-header>
+      <v-row justify="end">
+        <j-tooltip tipid='plugin-model-fitting-reestimate-all'>
+          <v-btn
+            tile
+            :elevation=0
+            x-small
+            dense 
+            color="turquoise"
+            dark
+            style="padding-left: 8px; padding-right: 6px;"
+            @click="reestimate_model_parameters">
+            <v-icon left small dense style="margin-right: 2px">mdi-restart</v-icon>
+            Re-estimate free parameters
+          </v-btn>
+        </j-tooltip>
+      </v-row>
       <v-row>
         <v-expansion-panels accordion>
           <v-expansion-panel
@@ -113,6 +129,24 @@
               >
                 <span><b>{{ item.id }}</b> model component not in equation</span>
               </v-row>
+              <v-row justify="end"
+                style="padding-top: 12px; padding-right: 2px"
+              >
+                <j-tooltip tipid='plugin-model-fitting-reestimate'>
+                  <v-btn
+                    tile
+                    :elevation=0
+                    x-small
+                    dense 
+                    color="turquoise"
+                    dark
+                    style="padding-left: 8px; padding-right: 6px;"
+                    @click="reestimate_model_parameters(item.id)">
+                    <v-icon left small dense style="margin-right: 2px">mdi-restart</v-icon>
+                    Re-estimate free parameters
+                  </v-btn>
+                </j-tooltip>
+              </v-row>
               <v-div
                 v-for="param in item.parameters"
                 :style="componentInEquation(item.id) ? '': 'opacity: 0.3'"