Hi,
I need to read some summaries from PI Server via PI Web Services to make an equivalent to DataLink functions:
PIAdvCalcExpFilVal() - filtered summary with PI PE formula as filter
PITimeFilterVal() - time true for expression
Does the GetPISummaryData method support filters? Or maybe there is a way to perform calculations via PI PE formula?
Hi Marcos,
Thanks for your answer, but from the manual (Version 2012):
• Filter
This property is not supported.
BTW, any idea about Time Filtered values?
Hello Pawel,
Filter is not supported for PISummaryManner object but yes for PIArcManner. I suggest you to read the section "Unsupported filters or parameters" of the PI Web Services 2012 manual for additional information of which classes and objects you are allowed to use the Filters property.
Concerning your problem, you may think of executing a PI Performance Equation through PI Web Services to perform calculations like:
pe:\\piservername\2*'sinusoid'
Do not forget to enable PI PE calculations on the web.config file as described on the section "Execution of PI Performance Equations not allowed".
Hope this helps you!
Hi Marcos,
Thank you. Do you know if there any plans to fully implement filtered calculations in PI Web Services like they are in PI-SDK?
Hello Pawel,
As far as I know, there are no plans since the PI Web Services team is investing all their efforts on the release of PI Web API. PI Web Services is developed using SOAP technology while PI Web API uses REST, which is becoming the default standard of industry. That is why if you are starting a new project, I recommend you using PI Web API instead of PI Web Services. Please refer to my blog post about the difference between both technologies and products.
Hope this helps!
Hi Pawel,
According to the manual, one of the members of PIArcManner object is Filter, which is a string expression in performance equation (PE) syntax used to filter values returned for PI points in Compressed mode, for example 'sinusoid' > 25.
Note: Filters are only supported for PI point retrieval in Compressed or Interpolated mode, or PI AF data references in Compressed mode. The PI point name in the filter expression must the point's tag name. Do not use the name of the PI AF data reference attribute.