Add delays chart in trajectories map

src/analysis/assets/templates/train_count.html → src/analysis/assets/templates/stats_chart.html

@@ -48,9 +48,11 @@
                     return currentTime;
                 }
 
-                const data = {{ this.get_data() }};
-                const startTime = moment(data[0]['x']);
-                const endTime = moment(data[data.length - 1]['x']);
+                const train_count_data = {{ this.get_train_count_data() }};
+                const delays_data = {{ this.get_delays_data() }};
+
+                const startTime = moment(train_count_data[0]['x']);
+                const endTime = moment(train_count_data[train_count_data.length - 1]['x']);
 
                 const timeHighlighter = {
                     id: 'timeHighlighter',
@@ -73,10 +75,18 @@
                 let chart = new Chart(ctx, {
                     type: 'line',
                     data: {
-                        datasets: [{
-                            data: data,
-                            label: "Circulating train count",
-                        }],
+                        datasets: [
+                            {
+                                data: train_count_data,
+                                label: "Circulating train count",
+                                yAxisID: 'y',
+                            },
+                            {
+                                data: delays_data,
+                                label: "Mean delay",
+                                yAxisID: 'y1',
+                            }
+                        ],
                     },
                     options: {
                         scales: {
@@ -90,6 +100,20 @@
                                     isoWeekday: true,
                                 }
                             },
+                            y: {
+                                display: true,
+                                type: 'linear',
+                                position: 'left',
+                            },
+                            y1: {
+                                display: true,
+                                type: 'linear',
+                                position: 'right',
+                                title: {
+                                    display: true,
+                                    text: "Minutes"
+                                }
+                            }
                         },
                         elements: {
                             point: {
@@ -98,12 +122,8 @@
                             }
                         },
                         plugins: {
-                            title: {
-                                display: true,
-                                text: "Circulating train count",
-                            },
                             legend: {
-                                display: false,
+                                display: true,
                             }
                         },
                     },

src/analysis/trajectories_map.py

@@ -229,7 +229,7 @@ def train_stop_geojson(st: pd.DataFrame, train: pd.DataFrame) -> list[dict]:
     return ret
 
 
-class TrainCountChart(MacroElement):
+class StatsChart(MacroElement):
     """Helper class to compute and embed the train count chart."""
 
     def __init__(self, df: pd.DataFrame, *args, **kwargs):
@@ -239,34 +239,48 @@ class TrainCountChart(MacroElement):
             df (pd.DataFrame): the train stop data
         """
         super().__init__(*args, **kwargs)
-        self.df = df
 
-    def get_data(self) -> list[dict[str, str | int]]:
-        """Utility function used by the template to get the computed data,
-        in a JS-likable format.
-        """
-        trains = self.df.groupby("train_hash")
-        trains_n = pd.DataFrame(index=self.df.train_hash.unique())
-        trains_n["departure"] = trains.first()["departure_actual"].fillna(
+        # Prepare dataset
+        trains = df.groupby("train_hash")
+        self.data = pd.DataFrame(index=df.train_hash.unique())
+        self.data["departure"] = trains.first()["departure_actual"].fillna(
             trains.first()["departure_expected"]
         )
-        trains_n["arrival"] = trains.last()["arrival_actual"].fillna(
+        self.data["arrival"] = trains.last()["arrival_actual"].fillna(
             trains.first()["arrival_expected"]
         )
+        self.data["delay"] = trains.mean(numeric_only=True)["departure_delay"].fillna(
+            trains.mean(numeric_only=True)["arrival_delay"]
+        )
 
-        js_dataset: list[dict[str, str | int]] = []
-        for time in fill_time(trains_n.departure.min(), trains_n.arrival.max()):
-            js_dataset.append(
+    def get_train_count_data(self) -> list[dict[str, str | int]]:
+        """Return circulating train count in a JS-likable format."""
+        ret: list[dict[str, str | int]] = []
+        for time in fill_time(self.data.departure.min(), self.data.arrival.max()):
+            subset: pd.DataFrame = self.data.loc[
+                (time >= self.data.departure) & (time <= self.data.arrival)
+            ]
+            ret.append(
+                {
+                    "x": time.isoformat(),
+                    "y": len(subset),
+                }
+            )
+        return ret
+
+    def get_delays_data(self) -> list[dict[str, str | float]]:
+        ret: list[dict[str, str | float]] = []
+        for time in fill_time(self.data.departure.min(), self.data.arrival.max()):
+            subset: pd.DataFrame = self.data.loc[
+                (time >= self.data.departure) & (time <= self.data.arrival)
+            ]
+            ret.append(
                 {
                     "x": time.isoformat(),
-                    "y": len(
-                        trains_n.loc[
-                            (time >= trains_n.departure) & (time <= trains_n.arrival)
-                        ]
-                    ),
+                    "y": subset.delay.mean() if len(subset) > 20 else "NaN",
                 }
             )
-        return js_dataset
+        return ret
 
 
 class MarkerLegend(MacroElement):
@@ -325,8 +339,8 @@ def build_map(st: pd.DataFrame, df: pd.DataFrame) -> None:
     m.get_root().add_child(legend)
 
     # Add train count chart
-    macro = TrainCountChart(df)
-    with open(ASSETS_PATH / "templates" / "train_count.html", "r") as f:
+    macro = StatsChart(df)
+    with open(ASSETS_PATH / "templates" / "stats_chart.html", "r") as f:
         macro._template = Template("\n".join(f.readlines()))
     m.get_root().add_child(macro)