Technical Implementation
import pandas as pd
from datetime import date, timedelta
from typing import Dict, Any, List, Optional
from dataclasses import dataclass, field
from enum import Enum
class LinkStatus(Enum):
LINKED = "linked"
UNLINKED = "unlinked"
PARTIAL = "partial"
@dataclass class ScheduleActivity: activity_id: str activity_name: str start_date: date end_date: date duration_days: int wbs_code: str predecessors: List[str] = field(default_factory=list)
@dataclass class BIMElement: element_id: str element_name: str category: str level: str zone: str volume: float = 0 area: float = 0
@dataclass class BIMScheduleLink: link_id: str activity_id: str element_ids: List[str] link_type: str # install, remove, temporary status: LinkStatus
class BIMSchedule4D: def init(self, project_name: str): self.project_name = project_name self.activities: Dict[str, ScheduleActivity] = {} self.elements: Dict[str, BIMElement] = {} self.links: Dict[str, BIMScheduleLink] = {} self._link_counter = 0
def import_schedule(self, schedule_data: List[Dict[str, Any]]):
for act in schedule_data:
activity = ScheduleActivity(
activity_id=act['id'],
activity_name=act['name'],
start_date=act['start'],
end_date=act['end'],
duration_days=(act['end'] - act['start']).days,
wbs_code=act.get('wbs', ''),
predecessors=act.get('predecessors', [])
)
self.activities[activity.activity_id] = activity
def import_elements(self, element_data: List[Dict[str, Any]]):
for elem in element_data:
element = BIMElement(
element_id=elem['id'],
element_name=elem['name'],
category=elem['category'],
level=elem.get('level', ''),
zone=elem.get('zone', ''),
volume=elem.get('volume', 0),
area=elem.get('area', 0)
)
self.elements[element.element_id] = element
def create_link(self, activity_id: str, element_ids: List[str],
link_type: str = "install") -> BIMScheduleLink:
if activity_id not in self.activities:
return None
self._link_counter += 1
link_id = f"LNK-{self._link_counter:05d}"
# Verify elements exist
valid_elements = [eid for eid in element_ids if eid in self.elements]
status = LinkStatus.LINKED if valid_elements else LinkStatus.UNLINKED
if valid_elements and len(valid_elements) < len(element_ids):
status = LinkStatus.PARTIAL
link = BIMScheduleLink(
link_id=link_id,
activity_id=activity_id,
element_ids=valid_elements,
link_type=link_type,
status=status
)
self.links[link_id] = link
return link
def auto_link_by_level(self, level: str, activity_id: str):
"""Auto-link all elements on a level to an activity."""
level_elements = [e.element_id for e in self.elements.values()
if e.level == level]
if level_elements:
return self.create_link(activity_id, level_elements)
return None
def get_elements_for_date(self, target_date: date) -> List[BIMElement]:
"""Get elements that should be visible on a specific date."""
visible_elements = []
for link in self.links.values():
activity = self.activities.get(link.activity_id)
if activity and activity.start_date <= target_date <= activity.end_date:
for elem_id in link.element_ids:
if elem_id in self.elements:
visible_elements.append(self.elements[elem_id])
return visible_elements
def get_unlinked_elements(self) -> List[BIMElement]:
linked_ids = set()
for link in self.links.values():
linked_ids.update(link.element_ids)
return [e for e in self.elements.values() if e.element_id not in linked_ids]
def get_unlinked_activities(self) -> List[ScheduleActivity]:
linked_activities = {link.activity_id for link in self.links.values()}
return [a for a in self.activities.values() if a.activity_id not in linked_activities]
def get_link_summary(self) -> Dict[str, Any]:
total_elements = len(self.elements)
linked_elements = len(set(
eid for link in self.links.values() for eid in link.element_ids
))
return {
'total_activities': len(self.activities),
'total_elements': total_elements,
'linked_elements': linked_elements,
'unlinked_elements': total_elements - linked_elements,
'total_links': len(self.links),
'link_coverage': round(linked_elements / total_elements * 100, 1) if total_elements > 0 else 0
}
def export_links(self, output_path: str):
data = []
for link in self.links.values():
activity = self.activities.get(link.activity_id)
data.append({
'Link ID': link.link_id,
'Activity': activity.activity_name if activity else '',
'Start': activity.start_date if activity else None,
'End': activity.end_date if activity else None,
'Elements': len(link.element_ids),
'Type': link.link_type,
'Status': link.status.value
})
pd.DataFrame(data).to_excel(output_path, index=False)
## Quick Start
```python
bim4d = BIMSchedule4D("Office Tower")
# Import schedule
bim4d.import_schedule([
{'id': 'A100', 'name': 'Foundation', 'start': date(2024, 1, 1), 'end': date(2024, 2, 28)},
{'id': 'A200', 'name': 'Structure L1', 'start': date(2024, 3, 1), 'end': date(2024, 4, 30)}
])
# Import elements
bim4d.import_elements([
{'id': 'E001', 'name': 'Footing F1', 'category': 'Foundation', 'level': 'Foundation'},
{'id': 'E002', 'name': 'Column C1', 'category': 'Structure', 'level': 'Level 1'}
])
# Create links
bim4d.create_link('A100', ['E001'])
bim4d.create_link('A200', ['E002'])
summary = bim4d.get_link_summary()
print(f"Link coverage: {summary['link_coverage']}%")
Resources
- DDC Book: Chapter 3.3 - 4D BIM