Rockwell Automation FactoryTalk Historian SE ProcessBook 3.2 User Guide - Manual (Page 158)

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FactoryTalk Historian ProcessBook User Guide
140
Y Tags, paired by
timestamps To pair values by time, rather than by list position, choose one of
these retrieval methods: Synchronize, Match, Match or Previous, or
Match or Next.
 Synchronize
Synchronizes data found for X with data for Y using the
timestamps for the X data. This may result in interpolated data
values for Y.
 Match
Find the event for Y corresponding to the exact time stamp as X. If
no matching event is found, no match is made for that X value.
 Match or Previous
Find the event for Y corresponding to the exact time stamp as X. If
there is none, find the event that is the closest but earlier in time.
 Match or Next
Find the event for Y corresponding to the exact time stamp as X. If
there is none, find the event that is the closest, but later in time.
Synchronize and
Match
Use different PI SDK value retrieval methods. Synchronize uses
TimedValues. Match uses RecordedValues and then uses the values
where the timestamps match.
Note: Synchronize is disabled for ODBC and Custom data
sets.
If you select Synchronize or any of the Match options, the start and
end times for that tag are set the same as for the X tag and cannot
be changed.
Note: The XYPlot supports ODBC data sets that don't
contain timestamps. This type of entry must be plotted as a Y-
tag, and data values must be retrieved using the Recorded
retrieval method. If a tag is changed from a Y tag to an X tag
and has a value for Retrieval Method that is only valid for Y
tags, the method is changed to Interpolated. If the tag is a
data set, the method is changed to Recorded.
In all cases, if a pair is not made, the unmatched X or Y events are
ignored.
Use for all Y tags Selecting this box indicates that the Y-tags data retrieval mechanism
applies for all Y-tags. If one of the tags is a Custom or ODBC data set
and the selection mechanism is Interpolated or Synchronize, the
selection mechanism will be Recorded or Match respectively for that
tag only.