Shape features derived from the ellipse parameters.
The operator excentricity calculates three shape features derived from the geometric moments.
Definition: If the ellipse radii $ra$, $rb$ and the area $F$ of the region are given (see moments, elliptic_axis), the following applies: Anisometry = ra / rb Bulkiness = 4 pi ra rb / F StructureFactor = (4 pi rb - F) / FIn case of empty region all parameters have the value 0.0 if no other behavior was set (see set_system).
Regions (input_object) |
region(-array) -> object |
Region(s) to be examined. |
Anisometry (output_control) |
real(-array) -> real |
Shape feature (in case of a circle = 1.0). | |
Assertion: Anisometry >= 1.0 |
Bulkiness (output_control) |
real(-array) -> real |
Calculated shape feature. |
StructureFactor (output_control) |
real(-array) -> real |
Calculated shape feature. |
If F is the area of the region the mean runtime complexity is O(F).
The operator excentricityreturns the value TRUE if the input is not empty. The behavior in case of empty input (no input regions available) is set via the operator set_system(::'no_object_result',<Result>:). The behavior in case of empty region (the region is the empty set) is set via set_system(::'empty_region_result',<Result>:). If necessary an exception is raised.
threshold__, regiongrowing__, connection
elliptic_axis, moments, select_shape, area_center