Stream GetInterpolated

Retrieves interpolated values over the specified time range at the specified sampling interval.

Remarks

Any time series value in the response that contains an 'Errors' property indicates PI Web API encountered a handled error during the transfer of the response stream. See Error Handling for more information.

Request

GET streams/{webId}/interpolated

URL Parameters

• webId

  The ID of the stream. See WebID for more information.

• startTime

  An optional start time. The default is '*-1d' for element attributes and points. For event frame attributes, the default is the event frame's start time, or '*-1d' if that is not set. See Time Strings for more information.

• endTime

  An optional end time. The default is '*' for element attributes and points. For event frame attributes, the default is the event frame's end time, or '*' if that is not set. Note that if endTime is earlier than startTime, the resulting values will be in time-descending order. See Time Strings for more information.

• timeZone

  The time zone in which the time string will be interpreted. This parameter will be ignored if a time zone is specified in the time string, unless the time range crosses a daylight savings time boundary and an interval is specified. If no time zone is specified in either places, the PI Web API server time zone will be used. See Time Zone for more information.

• interval

  The sampling interval, in AFTimeSpan format. The default is '1h'.

• syncTime

  An optional start time anchor, in AFTime format. When specified, interpolated data retrieval will use the sync time as the origin for calculating the interval times. See Sync Time for more information.

• syncTimeBoundaryType

  An optional string specifying the boundary type to use when applying a syncTime. The allowed values are 'Inside' and 'Outside'. The default is 'Inside'. See Boundary Type for more information.

• desiredUnits

  The name or abbreviation of the desired units of measure for the returned value, as found in the UOM database associated with the attribute. If not specified for an attribute, the attribute's default unit of measure is used. If the underlying stream is a point, this value may not be specified, as points are not associated with a unit of measure.

• filterExpression

  An optional string containing a filter expression. Expression variables are relative to the data point. Use '.' to reference the containing attribute. If the attribute does not support filtering, the filter will be ignored. The default is no filtering.

• includeFilteredValues

  Specify 'true' to indicate that values which fail the filter criteria are present in the returned data at the times where they occurred with a value set to a 'Filtered' enumeration value with bad status. Repeated consecutive failures are omitted.

• selectedFields

  List of fields to be returned in the response, separated by semicolons (;). If this parameter is not specified, all available fields will be returned. See Selected Fields for more information.

Status Codes

200: The values that meet the specified conditions.

400: The request was malformed.

409: The data reference does not support this method, or the supplied filter expression is unsupported, or the desired units of measure are incompatible.

Sample Response Body

{
  "Items": [
    {
      "Timestamp": "2014-07-22T14:00:00Z",
      "UnitsAbbreviation": "m",
      "Good": true,
      "Questionable": false,
      "Substituted": false,
      "Annotated": false,
      "Value": 12.3
    },
    {
      "Timestamp": "2014-07-22T14:00:00Z",
      "UnitsAbbreviation": "m",
      "Good": true,
      "Questionable": false,
      "Substituted": false,
      "Annotated": false,
      "Value": 12.3
    }
  ],
  "Links": {}
}