chord_distribution ( Regions : : : Foreground, Background )

Distribute the chord lengths of a region.

The operator chord_distribution calculates the distribution of the chord lengths of a region of the fore- and background. The frequency of the occurrence of a certain length is calculated. Chords of infinite length are not counted. As many values are passed as set by the maximum length of fore- or background, respectively. The length of both tuples usually differs. The first entry of the tuples is always 0 (no chords of the length 0). If there are no blanks the empty tuple is passed at Background. Analogously the empty tuple is passed in case of an empty region at Foreground.


Parameters

Regions (input_object)
region -> object
Region to be examined.

Foreground (output_control)
integer-array -> integer
Length distribution of the region (foreground).

Background (output_control)
integer-array -> integer
Length distribution of the background.


Complexity

If n is the number of chords of the region the runtime complexity is O(n).


Result

The operator chord_distribution returns 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>:). If more than one region is passed an exception is raised.


Possible Predecessors

threshold__, select_obj


Alternatives

fetch_chord


See also

num_chord



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