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The Delft-Fews Published interface format (PI) consists of a number of xsd schemas defining a number of XML formats for the exchange of datedata. The timeseries format deals with (scalar) timeseries data.
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A detailed description of all PI formats is can be found at http://public.deltares.nl/display/FEWSDOC/The+Delft-Fews+Published+interface+%28PI%29. The latest versions of the schema files are always available at the Deltares website at: http://fews.wldelft.nl/schemas/version1.0/pi-schemas/pi_timeseries.xsd
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