bim-qto"

# BIM Quantity Takeoff ## Overview Quantity Takeoff (QTO) extracts measurable quantities from BIM models. This skill processes BIM exports to generate grouped quantity reports for cost estimation. ## Python Implementation ```python import pandas as pd import numpy as np from typing import Dict, Any, List, Optional, Tuple from dataclasses import dataclass, field from enum import Enum class QTOUnit(Enum): """Quantity takeoff measurement units.""" COUNT = "ea" LENGTH = "m" AREA = "m2" VOLUME = "m3" WEIGHT = "kg" LINEAR_FOOT = "lf" SQUARE_FOOT = "sf" CUBIC_YARD = "cy" @dataclass class QTOItem: """Single QTO line item.""" category: str type_name: str description: str quantity: float unit: str level: Optional[str] = None material: Optional[str] = None element_count: int = 0 @dataclass class QTOReport: """Complete QTO report.""" project_name: str items: List[QTOItem] total_elements: int categories: int generated_date: str class BIMQuantityTakeoff: """Extract quantities from BIM data.""" # Column mappings for different BIM exports COLUMN_MAPPINGS = { 'type': ['Type Name', 'TypeName', 'type_name', 'Family and Type', 'IfcType'], 'category': ['Category', 'category', 'IfcClass', 'Element Category'], 'level': ['Level', 'level', 'Building Storey', 'BuildingStorey', 'Floor'], 'volume': ['Volume', 'volume', 'Volume (m³)', 'Qty_Volume'], 'area': ['Area', 'area', 'Surface Area', 'Area (m²)', 'Qty_Area'], 'length': ['Length', 'length', 'Length (m)', 'Qty_Length'], 'count': ['Count', 'count', 'Quantity', 'ElementCount'], 'material': ['Material', 'material', 'Structural Material', 'MaterialName'] } def __init__(self, df: pd.DataFrame): """Initialize with BIM data DataFrame.""" self.df = df self.column_map = self._detect_columns() def _detect_columns(self) -> Dict[str, str]: """Detect which columns exist in data.""" mapping = {} for standard, variants in self.COLUMN_MAPPINGS.items(): for variant in variants: if variant in self.df.columns: mapping[standard] = variant break return mapping def get_column(self, standard_name: str) -> Optional[str]: """Get actual column name from standard name.""" return self.column_map.get(standard_name) def group_by_type(self, sum_column: str = 'volume') -> pd.DataFrame: """Group quantities by type name.""" type_col = self.get_column('type') qty_col = self.get_column(sum_column) if type_col is None: raise ValueError("Type column not found") if qty_col is None: # Fall back to count result = self.df.groupby(type_col).size().reset_index(name='count') else: result = self.df.groupby(type_col).agg({ qty_col: 'sum' }).reset_index() result['count'] = self.df.groupby(type_col).size().values result.columns = ['Type', 'Quantity', 'Count'] if len(result.columns) == 3 else ['Type', 'Count'] return result.sort_values('Count', ascending=False) def group_by_category(self, sum_column: str = 'volume') -> pd.DataFrame: """Group quantities by category.""" cat_col = self.get_column('category') qty_col = self.get_column(sum_column) if cat_col is None: raise ValueError("Category column not found") agg_dict = {} if qty_col: agg_dict[qty_col] = 'sum' if agg_dict: result = self.df.groupby(cat_col).agg(agg_dict).reset_index() result['count'] = self.df.groupby(cat_col).size().values else: result = self.df.groupby(cat_col).size().reset_index(name='count') return result.sort_values('count', ascending=False) def group_by_level(self, sum_column: str = 'volume') -> pd.DataFrame: """Group quantities by building level.""" level_col = self.get_column('level') qty_col = self.get_column(sum_column) if level_col is None: raise ValueError("Level column not found") agg_dict = {} if qty_col: agg_dict[qty_col] = 'sum' if agg_dict: result = self.df.groupby(level_col).agg(agg_dict).reset_index() result['count'] = self.df.groupby(level_col).size().values else: result = self.df.groupby(level_col).size().reset_index(name='count') return result def pivot_by_level_and_type(self) -> pd.DataFrame: """Create pivot table: levels as rows, types as columns.""" level_col = self.get_column('level') type_col = self.get_column('type') if level_col is None or type_col is None: raise ValueError("Level or Type column not found") pivot = pd.crosstab( self.df[level_col], self.df[type_col], margins=True ) return pivot def filter_by_category(self, categories: List[str]) -> 'BIMQuantityTakeoff': """Filter to specific categories.""" cat_col = self.get_column('category') if cat_col is None: raise ValueError("Category column not found") filtered_df = self.df[self.df[cat_col].isin(categories)] return BIMQuantityTakeoff(filtered_df) def filter_by_level(self, levels: List[str]) -> 'BIMQuantityTakeoff': """Filter to specific levels.""" level_col = self.get_column('level') if level_col is None: raise ValueError("Level column not found") filtered_df = self.df[self.df[level_col].isin(levels)] return BIMQuantityTakeoff(filtered_df) def get_walls(self) -> pd.DataFrame: """Get wall quantities.""" cat_col = self.get_column('category') if cat_col: walls = self.df[self.df[cat_col].str.contains('Wall', case=False, na=False)] return BIMQuantityTakeoff(walls).group_by_type() return pd.DataFrame() def get_floors(self) -> pd.DataFrame: """Get floor/slab quantities.""" cat_col = self.get_column('category') if cat_col: floors = self.df[self.df[cat_col].str.contains('Floor|Slab', case=False, na=False)] return BIMQuantityTakeoff(floors).group_by_type() return pd.DataFrame() def get_doors(self) -> pd.DataFrame: """Get door quantities.""" cat_col = self.get_column('category') if cat_col: doors = self.df[self.df[cat_col].str.contains('Door', case=False, na=False)] return BIMQuantityTakeoff(doors).group_by_type() return pd.DataFrame() def get_windows(self) -> pd.DataFrame: """Get window quantities.""" cat_col = self.get_column('category') if cat_col: windows = self.df[self.df[cat_col].str.contains('Window', case=False, na=False)] return BIMQuantityTakeoff(windows).group_by_type() return pd.DataFrame() def generate_report(self, project_name: str = "Project") -> QTOReport: """Generate complete QTO report.""" from datetime import datetime items = [] type_col = self.get_column('type') cat_col = self.get_column('category') level_col = self.get_column('level') vol_col = self.get_column('volume') area_col = self.get_column('area') mat_col = self.get_column('material') # Group by type grouped = self.df.groupby(type_col if type_col else self.df.columns[0]) for type_name, group in grouped: # Determine primary quantity qty = 0 unit = QTOUnit.COUNT.value if vol_col and vol_col in group.columns: qty = group[vol_col].sum() unit = QTOUnit.VOLUME.value elif area_col and area_col in group.columns: qty = group[area_col].sum() unit = QTOUnit.AREA.value else: qty = len(group) unit = QTOUnit.COUNT.value # Get category and material category = group[cat_col].iloc[0] if cat_col and cat_col in group.columns else "" material = group[mat_col].iloc[0] if mat_col and mat_col in group.columns else "" level = group[level_col].iloc[0] if level_col and level_col in group.columns else "" items.append(QTOItem( category=str(category), type_name=str(type_name), description=str(type_name), quantity=round(qty, 2), unit=unit, level=str(level) if level else None, material=str(material) if material else None, element_count=len(group) )) return QTOReport( project_name=project_name, items=items, total_elements=len(self.df), categories=self.df[cat_col].nunique() if cat_col else 0, generated_date=datetime.now().isoformat() ) def to_excel(self, output_path: str, project_name: str = "Project"): """Export QTO to Excel with multiple sheets.""" with pd.ExcelWriter(output_path, engine='openpyxl') as writer: # Summary by category self.group_by_category().to_excel( writer, sheet_name='By Category', index=False) # Summary by type self.group_by_type().to_excel( writer, sheet_name='By Type', index=False) # Level breakdown try: self.pivot_by_level_and_type().to_excel( writer, sheet_name='Level-Type Matrix') except: pass # Walls walls = self.get_walls() if not walls.empty: walls.to_excel(writer, sheet_name='Walls', index=False) # Doors and Windows doors = self.get_doors() if not doors.empty: doors.to_excel(writer, sheet_name='Doors', index=False) windows = self.get_windows() if not windows.empty: windows.to_excel(writer, sheet_name='Windows', index=False) return output_path ``` ## Quick Start ```python # Load BIM export df = pd.read_excel("revit_export.xlsx") # Initialize QTO qto = BIMQuantityTakeoff(df) # Get quantities by type by_type = qto.group_by_type() print(by_type.head(10)) # Get wall schedule walls = qto.get_walls() print(walls) ``` ## Common Use Cases ### 1. Full QTO Report ```python qto = BIMQuantityTakeoff(df) report = qto.generate_report("Office Building") print(f"Elements: {report.total_elements}") for item in report.items[:5]: print(f"{item.type_name}: {item.quantity} {item.unit}") ``` ### 2. Level-by-Level Analysis ```python pivot = qto.pivot_by_level_and_type() print(pivot) ``` ### 3. Export to Excel ```python qto.to_excel("qto_report.xlsx", "My Project") ``` ## Resources - **DDC Book**: Chapter 3.2 - Quantity Take-Off