sis-commits mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "Martin Desruisseaux (JIRA)" <j...@apache.org>
Subject [jira] [Created] (SIS-79) Implement RangeSet.remove(E, E)
Date Fri, 22 Feb 2013 12:30:13 GMT
Martin Desruisseaux created SIS-79:
--------------------------------------

             Summary: Implement RangeSet.remove(E, E)
                 Key: SIS-79
                 URL: https://issues.apache.org/jira/browse/SIS-79
             Project: Spatial Information Systems
          Issue Type: Bug
          Components: Utilities
            Reporter: Martin Desruisseaux


The {{org.apache.sis.util.collection.RangeSet}} class has been ported to Apache SIS at the
exclusion of the implementation of the {{remove(E,E)}} method, which has been excluded for
licensing reasons. We need volunteer work for implementing that method.

A copy of the {{add(E,E)}} can be used as a starting point, then modified. The basic idea
is it to get the index of the given {{minValue}} and {{maxValue}} arguments using the {{binarySearch}}
method, then make some choices:

* If the given range is completely outside all {{RangeSet}} ranges, do nothing.
* If the given range fully contains one or many {{RangeSet}} ranges, remove all those ranges
by invoking the {{removeAt(int, int)}} method.
* If the given range is fully contained inside an existing range, split that existing range
in two smaller ranges: one for the part before the range to remove, and one for the part after
the range to remove. The {{insertAt(int, E, E)}} method will need to be invoked.
* If the given range partially overlaps an existing {{RangeSet}} range, edits the endpoints
of that range. No range are removed or inserted.

There is some tricks to keep in mind for hacking {{RangeSet}}:

* The internal {{array}} is a sequence of (_minimal_, _maximal_) value tupples for all ranges
included in this {{RangeSet}} instance.Even index are for minimal values and odd index are
for maximal values.
* If {{binarySearch}} returns a negative value, no exact match was found. To get the insertion
point (the index of the first value greater than the searched value), use {{index = ~index}}
(the tild operation, not the minus sign).
* To test if an index points to a minimal value (i.e. the index is an even number), use {{((index
& 1) == 0)}}.
* To test if an index points to a maximal value (i.e. the index is an odd number), use {{((index
& 1) != 0)}}.
* To force an index to be even (i.e. to point to the minimal value of the range) either be
leaving the index unchanged, or if the index was odd decrease the value by one, use {{index
&= ~1}}.
* To force an index to be odd (i.e. to point to the maximal value of the range) either by
leaving the index unchanged, or if the index was even increase the value by one, use {{index
|= 1}}.


--
This message is automatically generated by JIRA.
If you think it was sent incorrectly, please contact your JIRA administrators
For more information on JIRA, see: http://www.atlassian.com/software/jira

Mime
View raw message