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https://issues.apache.org/jira/browse/QUARKS-107?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=15227106#comment-15227106
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ASF GitHub Bot commented on QUARKS-107:
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Github user dlaboss commented on the pull request:
https://github.com/apache/incubator-quarks-website/pull/33#issuecomment-205981418
@ddebrunner, this [WIP] was prematurely merged when someone was bulk
merging a lot of pending requests. I'll leave things as is for now rather than
back them out and adjust pending your response to the question above.
> Add sample use of new Range class in recipe3 - detect value out of range?
> -------------------------------------------------------------------------
>
> Key: QUARKS-107
> URL: https://issues.apache.org/jira/browse/QUARKS-107
> Project: Quarks
> Issue Type: Improvement
> Reporter: Dale LaBossiere
> Assignee: Dale LaBossiere
> Labels: newbie
>
> Add sample use of new Range class in recipe3 - detect value out of range?
> Either or both of the recipe's existing samples could be use Range, or one of
> them could be cloned to use it.
> ```
> TStream<Double> simpleFiltered = temp.filter(tuple ->
> tuple < TEMP_LOW || tuple > TEMP_HIGH);
> // could be
> TStream<Double> simpleFiltered = temp.filter(Ranges.open(TEMP_LOW, TEMP_HIGH);
> TStream<Double> deadbandFiltered = Filters.deadband(temp,
> identity(), tuple -> tuple >= TEMP_LOW && tuple <= TEMP_HIGH);
> // could instead be
> TStream<Double> deadbandFiltered = Filters.deadband(temp,
> identity(), Ranges.closed(TEMP_LOW, TEMP_HIGH));
> ```
> Use of a Range simplifies the code a bit. I can also avoid mistakes if one's
> code "duplicates" the expressions for a particular range in multiple places.
> Using Range can be more compelling for the simplicity with which a range may
> be expressed and created from a config file for an app. e.g. imagine how one
> would express the range in a Properties config file. A range property value
> in a Properties file would simply be:
> ```
> # my sensor filter range
> myFilterRange=[71.0..98.0]
> ```
> and the app code to create the Range would simply be:
> ```
> Range<Double> myFilterRange =
> Ranges.valueOfDouble(props.getProperty("myFilterRange"));
> ```
> Another compelling case is making a filter range dynamically changeable, for
> example as a result of some received IoT "device command". The range could
> be declared like:
> ```
> AtomicReference<Range<Double>> myFilterRange = new AtomicReference<>(
> Ranges.valueOfDouble(props.getProperty("myFilterRange")); // initial
> range value
> // code in the device's set-filter-range cmd handler is ultimately:
> //
> myFilterRange.set(Ranges.valueOfDouble(the-new-range-string-from-the-cmd));
> // sets a new Range object
> // Using the changeable filter range is simply:
> TStream<Double> simpleFiltered = temp.filter(myFilterRange.get());
> ```
> Dynamic filter Predicates is probably a good recipe unto itself :-)
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