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# Table 1 Morphometrical parameters used in the analysis of the theoretical cells.

Parameter Units Explanation
Perim pixels Perimeter calculated from the centres of the boundary pixels
Area pixels2 The area inside the polygon defined by the perimeter
MinR pixels Radius of the inscribed circle centred at the centre of mass
MaxR pixels Radius of the enclosing circle centred at the centre of mass
Feret pixels Largest axis length
Breadth pixels The largest axis perpendicular to the Feret diameter
CHull pixels Convex Hull or convex polygon calculated from pixel centres
CArea pixels2 Area of the Convex Hull polygon
AspRatio none Aspect Ratio = Feret/Breadth
Circ none Circularity = 4*π*Area/Perimeter2, also called form factor
Roundness none Roundness = 4*Area/(π*Feret2)
AreaEquivD pixels Area of circle with equivalent diameter = sqrt((4/π)*Area)
PerimEquivD none Perimeter of circle with equivalent diameter = Area/π
EquivEllipseAr pixels2 Equivalent Ellipse Area = (π*Feret*Breadth)/4
Compactness none Compactness: sqrt((4/π)*Area)/Feret
Solidity none Solidity = Area/Convex_Area
Concavity pixels2 Concavity = Convex_Area - Area
Convexity none Convexity = Convex_Hull/Perimeter
Shape none Shape = Perimeter2/Area
RFactor none RFactor = Convex_Hull/(Feret*π)
ModRatio none Modification Ratio = (2*MinR)/Feret
Sphericity none Sphericity = MinR/MaxR
ArBBox pixels2 ArBBox = Feret*Breadth, area of the box along Feret diameter
Rectang none Rectangularity = Area/ArBBox
1. Here, the "pixel" units relate to length (the distance between the centre of one pixel and its neighbour), while pixels2 relate to area (the number of pixels). "None" are dimensionless values.