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Version: 7.9


This function is used in Python Scripting.


Reads processed values from the OPC-HDA server. Processed values are calculated values, based on the aggregate function requested for each item. The list of aggregates can be obtained by calling system.opchda.getAggregates().

Client Permission Restrictions

This scripting function has no Client Permission restrictions.


system.opchda.readProcessed(serverName, itemIds, startDate, endDate, resampleIntervalMS, aggregates)


StringserverNameThe name of the defined OPC-HDA server to read.
ListitemIdsA list of item ids to read.
ObjectstartDateThe starting date/time of the query.
ObjectendDateThe ending date/time of the query.
intresampleIntervalMSThe interval, in milliseconds, that each value should cover.
ListaggregatesA list which should be one-toone with the item ids requested, specifying the integer id of the aggregation function to use. The aggregation ids are defined in the OPC-HDA specification. The list of aggregates can also be obtained by calling system.opchda.getAggregates().


ReadResults[] - A list of read results which is one-to-one with the item IDs passed in. The ReadResult object has a serviceResult quality property that indicates whether the call was successful, and is itself a list of QualifiedValues.