3.2.1 Primary characters
Each primary character quantifies an aspect of urban morphology with respect to a particular element (as described above). As wide a range of characters as reasonably possible is initially calculated in order to capture as many different aspects of urban form as possible. The primary characters are calculated using momepy
. The initial set of characters is detailed in Table 3.1. The character descriptions are primarily adapted from Fleischmann (2021) Fleischmann (2021) and momepy
documentation.
Variable name  Index  Element  Description  H3 

blg_Height  Height  Building  Height of building 

blg_FloorArea  Floor area  Building  Floor area of building 

blg_Area  Area  Building  Area of building 

blg_Volume  Volume  Building  Volume of building 

blg_Perimeter  Perimeter  Building  Perimeter of building 

blg_CourtyardArea  Courtyard area  Building  Area of holes in buildings (aka courtyards) 

blg_FormFactor  Form factor  Building  Compactness of building 

blg_VolumeFacadeRatio  Volume to façade ratio  Building  Ratio of building volume to area of the façade, a proxy for volumetric compactness 

blg_CircularCompactness  Circular compactness  Building  Ratio of area of building’s enclosing circle to its area 

blg_Corners  Corners  Building  Number of corners the building has 

blg_Squareness  Squareness  Building  Squareness of building 

blg_EquivalentRectangularIndex  Equivalent rectangular Index  Building  Deviation of building from an equivalent rectangle 

blg_Elongation  Elongation  Building  Ratio of shorter to longer dimension of the minimum bounding rectangle, a proxy for the deviation of the shape from a square 

blg_CentroidCornersMean  Centroid to corner mean  Building  Mean distance from building centroid to its corners 

blg_CentroidCornersSD  Centroid to corner standard deviation  Building  Standard deviation of distance from building centroid to its corners 

blg_Orientation  Orientation  Building  Orientation of the building 

blg_SharedWallsRatio  Shared walls ratio  Building  Ratio of shared walls to total perimeter 

blg_CellAlignment  Cell alignment  Building  Calculate the difference between cell orientation and orientation of building  
tess_Orientation  Orientation  Tessellation cell  Orientation of the tessellation cell (calculated via the bounding rectangle)  
tess_LongestAxisLength  Longest axis length  Tessellation cell  Length of the longest axis of tessellation cell  
tess_Area  Area  Tessellation cell  Area of tessellation cell  
tess_CircularCompactness  Circular compactness  Tessellation cell  Ratio of area of tessellation cell’s enclosing circle to its area  
tess_EquivalentRectangularIndex  Equivalent rectangular Index  Tessellation cell  Deviation of tessellation cell from an equivalent rectangle  
tess_WeightedNeighbours  Weighted neighbours  Tessellation cell  Number of tessellation cell neighbours divided by the cell perimeter  
tess_CoverageAreaRatio  Coverage area ratio  Tessellation cell  Proportion of tessellation cell covered by a building  
tess_FloorAreaRatio  Floor area ratio  Tessellation cell  Ratio of floor area to tessellation cell area  
blk_Area  Area  Block  Area of block  
blk_Perimeter  Perimeter  Block  Perimeter of block  
blk_CircularCompactness  Circular compactness  Block  Ratio of area of block’s enclosing circle to area of block  
blk_EquivalentRectangularIndex  Equivalent rectangular Index  Block  Deviation of block from an equivalent rectangle  
blk_CompactnessWeightedAxis  Compactnessweighted axis  Block  Compactnessweighted axis of block, a proxy of permeability of an area  
blk_Orientation  Orientation  Block  Orientation of the block (calculated via its bounding rectangle)  
blk_WeightedNeighbours  Weighted neighbours  Block  Number of block neighbours divided by the block perimeter  
blk_WeightedBuildings  Weighted buildings  Block  Number of buildings within the block divided by the block area 