IfcCSV now supports grouping and group operations like concat, sum, min, max, etc.

src/blenderbim/blenderbim/bim/module/csv/operator.py

@@ -81,6 +81,7 @@ class ImportCsvAttributes(bpy.types.Operator):
             new.name = attribute["name"]
             new.header = attribute["header"]
             new.sort = attribute["sort"]
+            new.group = attribute["group"]
         return {"FINISHED"}
 
     def invoke(self, context, event):
@@ -102,7 +103,9 @@ class ExportCsvAttributes(bpy.types.Operator):
 
         data = {
             "query": tool.Search.export_filter_query(props.filter_groups),
-            "attributes": [{"name": a.name, "header": a.header, "sort": a.sort} for a in props.csv_attributes],
+            "attributes": [
+                {"name": a.name, "header": a.header, "sort": a.sort, "group": a.group} for a in props.csv_attributes
+            ],
         }
 
         with open(self.filepath, "w") as outfile:
@@ -148,9 +151,12 @@ class ExportIfcCsv(bpy.types.Operator):
         headers = [a.header for a in props.csv_attributes]
 
         sort = []
+        groups = []
         for attribute in props.csv_attributes:
             if attribute.sort != "NONE":
                 sort.append({"name": attribute.name, "order": attribute.sort})
+            if attribute.group != "NONE":
+                groups.append({"name": attribute.name, "type": attribute.group, "varies_value": attribute.varies_value})
 
         sep = props.csv_custom_delimiter if props.csv_delimiter == "CUSTOM" else props.csv_delimiter
         ifc_csv.export(
@@ -167,6 +173,7 @@ class ExportIfcCsv(bpy.types.Operator):
             bool_true=props.true_value,
             bool_false=props.false_value,
             sort=sort,
+            groups=groups,
         )
         return {"FINISHED"}
 

src/blenderbim/blenderbim/bim/module/csv/prop.py

@@ -36,6 +36,19 @@ class CsvAttribute(PropertyGroup):
     name: StringProperty(name="Query", default="class")
     header: StringProperty(name="Header Value", default="IFC Class")
     sort: EnumProperty(items=[("NONE", "None", ""), ("ASC", "Ascending", ""), ("DESC", "Descending", "")])
+    group: EnumProperty(
+        items=[
+            ("NONE", "None", ""),
+            ("GROUP", "Group", "All rows where this value is identical will be merged."),
+            ("CONCAT", "Concatenation", "Concatenate values if values vary within a group."),
+            ("VARIES", "Varies", "Show a custom value if values vary within a group."),
+            ("SUM", "Sum", "Sums the total value of rows in a group."),
+            ("AVERAGE", "Average", "Averages the total value of rows in a group."),
+            ("MIN", "Min", "Gets the minimum value of rows in a group."),
+            ("MAX", "Max", "Gets the maximum value of rows in a group."),
+        ]
+    )
+    varies_value: StringProperty(default="Varies", name="Varies Value")
 
 
 class CsvProperties(PropertyGroup):
@@ -81,5 +94,6 @@ class CsvProperties(PropertyGroup):
     )
     csv_custom_delimiter: StringProperty(default="", name="Custom Delimiter")
     should_show_settings: BoolProperty(default=False, name="Show Settings")
-    should_show_sort: BoolProperty(default=False, name="Show Sort")
+    should_show_sort: BoolProperty(default=False, name="Show Sorting")
+    should_show_group: BoolProperty(default=False, name="Show Grouping")
     should_load_from_memory: BoolProperty(default=False, name="Load from Memory")

src/blenderbim/blenderbim/bim/module/csv/ui.py

@@ -48,6 +48,7 @@ class BIM_PT_ifccsv(Panel):
             row.operator("bim.import_csv_attributes", icon="IMPORT", text="")
             row.operator("bim.export_csv_attributes", icon="EXPORT", text="")
         row.prop(props, "should_show_sort", icon="SORTSIZE", text="")
+        row.prop(props, "should_show_group", icon="OUTLINER_COLLECTION", text="")
         row.prop(props, "should_show_settings", icon="PREFERENCES", text="")
 
         if not IfcStore.get_file() or not props.should_load_from_memory:
@@ -90,8 +91,11 @@ class BIM_PT_ifccsv(Panel):
             row.prop(attribute, "name", text="")
             if props.should_show_sort:
                 row.prop(attribute, "sort", text="")
-            else:
+            if props.should_show_group:
-                row.prop(attribute, "header", text="")
+                row.prop(attribute, "group", text="")
+                if attribute.group == "VARIES":
+                    row.prop(attribute, "varies_value", text="")
+            row.prop(attribute, "header", text="")
             row.operator("bim.remove_csv_attribute", icon="X", text="").index = index
 
         row = layout.row(align=True)

src/ifccsv/ifccsv.py

@@ -28,6 +28,7 @@ import ifcopenshell
 import ifcopenshell.util.selector
 import ifcopenshell.util.element
 import ifcopenshell.util.schema
+from statistics import mean
 
 try:
     from odf.namespaces import OFFICENS
@@ -72,6 +73,7 @@ class IfcCsv:
         bool_true="YES",
         bool_false="NO",
         sort=None,
+        groups=None,
     ):
         self.ifc_file = ifc_file
         self.results = []
@@ -110,6 +112,65 @@ class IfcCsv:
             else:
                 self.headers.append(attribute)
 
+        if groups:
+            group_results = {}
+            group_indices = {}
+            group_values = {}
+            group_varies_values = {}
+
+            for group in groups:
+                index = attributes.index(group["name"])
+                group_indices.setdefault(group["type"], [])
+                group_indices[group["type"]].append(index)
+                if group["type"] == "VARIES":
+                    group_varies_values[index] = group["varies_value"]
+
+            for row in self.results:
+                key = "-".join([str(row[gi]) for gi in group_indices.get("GROUP", [])])
+                for group_type, gis in group_indices.items():
+                    if group_type in ("CONCAT", "VARIES"):
+                        for gi in gis:
+                            group_values.setdefault(key, {}).setdefault(gi, set())
+                            group_values[key][gi].add(str(row[gi]))
+                    elif group_type in ("SUM", "AVERAGE", "MIN", "MAX"):
+                        for gi in gis:
+                            group_values.setdefault(key, {}).setdefault(gi, [])
+                            try:
+                                value = float(row[gi])
+                            except:
+                                continue
+                            group_values[key][gi].append(value)
+                group_results[key] = row
+
+            for group_type, gis in group_indices.items():
+                if group_type == "CONCAT":
+                    for key, result in group_results.items():
+                        for gi in gis:
+                            result[gi] = ", ".join(group_values[key][gi])
+                elif group_type == "VARIES":
+                    for key, result in group_results.items():
+                        for gi in gis:
+                            if len(group_values[key][gi]) > 1:
+                                result[gi] = group_varies_values[gi]
+                elif group_type == "SUM":
+                    for key, result in group_results.items():
+                        for gi in gis:
+                            result[gi] = sum(group_values[key][gi])
+                elif group_type == "AVERAGE":
+                    for key, result in group_results.items():
+                        for gi in gis:
+                            result[gi] = mean(group_values[key][gi])
+                elif group_type == "MIN":
+                    for key, result in group_results.items():
+                        for gi in gis:
+                            result[gi] = min(group_values[key][gi])
+                elif group_type == "MAX":
+                    for key, result in group_results.items():
+                        for gi in gis:
+                            result[gi] = max(group_values[key][gi])
+
+            self.results = group_results.values()
+
         if sort:
             def natural_sort(value):
                 if isinstance(value, str):

src/ifcopenshell-python/ifcopenshell/util/selector.py

@@ -673,6 +673,7 @@ class Selector:
                     value = len(list(value))
                 elif isinstance(value, (list, tuple)):
                     value = len(value)
+                value = 1
             elif key == "class":
                 value = value.is_a()
             elif key == "id":