Operator Reference
orientation_region (Operator)
orientation_region
— Orientation of a region.
Signature
Description
The operator orientation_region
calculates the
orientation of the region. The operator is based on elliptic_axis
.
In addition the point on the contour with maximal distance to the
center of gravity is calculated. If, in the rotated coordinate system,
the column coordinate of this point is less than the column coordinate
of the center of gravity, the value of is added to the angle.
In the documentation of this chapter (Regions / Features), you can find an image illustrating regions which vary in their orientation.
If more than one region is passed the results are stored in tuples, the index of a value in the tuple corresponding to the index of a region in the input.
In case of empty region all parameters have the value 0.0 if no other
behavior was set
(see set_system('no_object_result',<Result>)
).
Execution Information
- Multithreading type: reentrant (runs in parallel with non-exclusive operators).
- Multithreading scope: global (may be called from any thread).
- Automatically parallelized on tuple level.
Parameters
Regions
(input_object) region(-array) →
object
Region(s) to be examined.
Phi
(output_control) angle.rad(-array) →
(real)
Orientation of region (arc measure).
Assertion:
- pi <= Phi && Phi < pi
Complexity
If F is the area of a region the mean runtime complexity is O(sqrt(F)).
Result
The operator orientation_region
returns the value 2 (
H_MSG_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.
Possible Predecessors
threshold
,
regiongrowing
,
connection
Possible Successors
Alternatives
elliptic_axis
,
smallest_rectangle2
See also
moments_region_2nd
,
line_orientation
Module
Foundation