Add fields to trajs

Author: anitagraser

README.md

@@ -1,6 +1,6 @@
 # QGIS Processing Trajectools
 
-The Trajectools plugin adds trajectory tools to the QGIS Processing toolbox. 
+The Trajectools plugin adds trajectory analysis algorithms to the QGIS Processing toolbox. 
 
 ![Trajectools screenshot](screenshots/trajectools.PNG)
 ![Trajectools clipping screenshot](screenshots/trajectools2.PNG)

qgis_processing/createTrajectoriesAlgorithm.py

@@ -4,7 +4,6 @@
 
 sys.path.append("..")
 
-from .qgisUtils import tc_to_sink, traj_to_sink
 from .trajectoriesAlgorithm import TrajectoriesAlgorithm
 
 
@@ -45,6 +44,6 @@ def createInstance(self):
         return type(self)()
 
     def processTc(self, tc, parameters, context):
-        tc_to_sink(tc, self.sink_pts, self.fields_pts, self.timestamp_field)
+        self.tc_to_sink(tc)
         for traj in tc.trajectories:
-            traj_to_sink(traj, self.sink_trajs)
+            self.traj_to_sink(traj)

qgis_processing/overlayAlgorithm.py

@@ -11,7 +11,6 @@
 
 sys.path.append("..")
 
-from .qgisUtils import tc_to_sink, traj_to_sink
 from .trajectoriesAlgorithm import TrajectoriesAlgorithm
 
 
@@ -67,9 +66,9 @@ def processTc(self, tc, parameters, context):
         extent = self.parameterAsExtent(parameters, self.EXTENT, context)
         extent = shapely.wkt.loads(extent.asWktPolygon())
         clipped = tc.clip(extent)
-        tc_to_sink(clipped, self.sink_pts, self.fields_pts, self.timestamp_field)
+        self.tc_to_sink(clipped)
         for traj in clipped:
-            traj_to_sink(traj, self.sink_trajs)
+            self.traj_to_sink(traj)
 
 
 class ClipTrajectoriesByPolygonLayer(OverlayTrajectoriesAlgorithm):
@@ -116,6 +115,6 @@ def processTc(self, tc, parameters, context):
         for feature in vlayer.getFeatures():
             extent = shapely.wkt.loads(feature.geometry().asWkt())
             clipped = tc.clip(extent)
-            tc_to_sink(clipped, self.sink_pts, self.fields_pts, self.timestamp_field)
+            self.tc_to_sink(clipped)
             for traj in clipped:
-                traj_to_sink(traj, self.sink_trajs)
+                self.traj_to_sink(traj)

qgis_processing/qgisUtils.py

@@ -49,26 +49,3 @@ def feature_from_gdf_row(row):
     f.setGeometry(QgsGeometry.fromPointXY(QgsPointXY(row.geometry.x, row.geometry.y)))
     f.setAttributes(row.values.tolist()[:-1])
     return f
-
-
-def tc_to_sink(tc, sink, fields, timestamp_field):
-    try:
-        gdf = tc.to_point_gdf()
-    except ValueError:  # when the tc is empty
-        return
-    gdf[timestamp_field] = gdf.index.astype(str)
-    names = [field.name() for field in fields]
-    names.append("geometry")
-    gdf = gdf[names]
-
-    for _, row in gdf.iterrows():
-        f = feature_from_gdf_row(row)
-        sink.addFeature(f, QgsFeatureSink.FastInsert)
-
-
-def traj_to_sink(traj, sink):
-    line = QgsGeometry.fromWkt(traj.to_linestringm_wkt())
-    f = QgsFeature()
-    f.setGeometry(line)
-    f.setAttributes([traj.id])
-    sink.addFeature(f, QgsFeatureSink.FastInsert)

qgis_processing/splitTrajectoriesAlgorithm.py

@@ -11,7 +11,6 @@
 
 sys.path.append("..")
 
-from .qgisUtils import tc_to_sink, traj_to_sink
 from .trajectoriesAlgorithm import TrajectoriesAlgorithm
 
 
@@ -69,9 +68,9 @@ def processTc(self, tc, parameters, context):
         time_gap = pd.Timedelta(time_gap).to_pytimedelta()
         for traj in tc.trajectories:
             splits = ObservationGapSplitter(traj).split(gap=time_gap)
-            tc_to_sink(splits, self.sink_pts, self.fields_pts, self.timestamp_field)
+            self.tc_to_sink(splits)
             for split in splits:
-                traj_to_sink(split, self.sink_trajs)
+                self.traj_to_sink(split)
 
 
 class TemporalSplitterAlgorithm(SplitTrajectoriesAlgorithm):
@@ -122,9 +121,9 @@ def processTc(self, tc, parameters, context):
         split_mode = self.SPLIT_MODE_OPTIONS[split_mode]
         for traj in tc.trajectories:
             splits = TemporalSplitter(traj).split(mode=split_mode)
-            tc_to_sink(splits, self.sink_pts, self.fields_pts, self.timestamp_field)
+            self.tc_to_sink(splits)
             for split in splits:
-                traj_to_sink(split, self.sink_trajs)
+                self.traj_to_sink(split)
 
 
 class StopSplitterAlgorithm(SplitTrajectoriesAlgorithm):
@@ -181,6 +180,6 @@ def processTc(self, tc, parameters, context):
             splits = StopSplitter(traj).split(
                 max_diameter=max_diameter, min_duration=min_duration
             )
-            tc_to_sink(splits, self.sink_pts, self.fields_pts, self.timestamp_field)
+            self.tc_to_sink(splits)
             for split in splits:
-                traj_to_sink(split, self.sink_trajs)
+                self.traj_to_sink(split)

qgis_processing/trajectoriesAlgorithm.py

@@ -14,14 +14,25 @@
     QgsProcessingParameterString,
     QgsField,
     QgsFields,
+    QgsFeature,
+    QgsGeometry,
+    QgsFeatureSink,
 )
 
 sys.path.append("..")
 
-from .qgisUtils import tc_from_pt_layer
+from .qgisUtils import tc_from_pt_layer, feature_from_gdf_row
 
 pluginPath = os.path.dirname(__file__)
 
+TIME_FACTOR = {
+    "s": 1,
+    "min": 60,
+    "h": 3600,
+    "d": 3600 * 24,
+    "a": 3600 * 24 * 365,
+}
+
 
 class TrajectoriesAlgorithm(QgsProcessingAlgorithm):
     # script parameters
@@ -112,15 +123,15 @@ def processAlgorithm(self, parameters, context, feedback):
         self.timestamp_field = self.parameterAsFields(
             parameters, self.TIMESTAMP_FIELD, context
         )[0]
-        speed_units = self.parameterAsString(
+        self.speed_units = self.parameterAsString(
             parameters, self.SPEED_UNIT, context
         ).split("/")
         crs = self.input_layer.sourceCrs()
 
         tc = tc_from_pt_layer(
             self.input_layer, self.timestamp_field, self.traj_id_field
         )
-        tc.add_speed(units=tuple(speed_units), overwrite=True)
+        tc.add_speed(units=tuple(self.speed_units), overwrite=True)
         tc.add_direction(overwrite=True)
 
         self.fields_pts = self.get_pt_fields(
@@ -179,6 +190,39 @@ def get_pt_fields(self, fields_to_add=[]):
         return fields
 
     def get_traj_fields(self):
+        length_units = f"{self.speed_units[0]}"
+        speed_units = f"{self.speed_units[0]}{self.speed_units[1]}"
         fields = QgsFields()
         fields.append(QgsField(self.traj_id_field, QVariant.String))
+        fields.append(QgsField("start_time", QVariant.String))
+        fields.append(QgsField("end_time", QVariant.String))
+        fields.append(QgsField("duration_seconds", QVariant.Double))
+        fields.append(QgsField(f"length_{length_units}", QVariant.Double))
+        fields.append(QgsField(f"speed_{speed_units}", QVariant.Double))
         return fields
+
+    def traj_to_sink(self, traj):
+        line = QgsGeometry.fromWkt(traj.to_linestringm_wkt())
+        f = QgsFeature()
+        f.setGeometry(line)
+        start_time = traj.get_start_time().isoformat()
+        end_time = traj.get_end_time().isoformat()
+        duration = float(traj.get_duration().total_seconds())
+        length = traj.get_length(units=self.speed_units[0])
+        speed = length / (duration / TIME_FACTOR[self.speed_units[1]])
+        f.setAttributes([traj.id, start_time, end_time, duration, length, speed])
+        self.sink_trajs.addFeature(f, QgsFeatureSink.FastInsert)
+
+    def tc_to_sink(self, tc):
+        try:
+            gdf = tc.to_point_gdf()
+        except ValueError:  # when the tc is empty
+            return
+        gdf[self.timestamp_field] = gdf.index.astype(str)
+        names = [field.name() for field in self.fields_pts]
+        names.append("geometry")
+        gdf = gdf[names]
+
+        for _, row in gdf.iterrows():
+            f = feature_from_gdf_row(row)
+            self.sink_pts.addFeature(f, QgsFeatureSink.FastInsert)