Stream GetPlot

Retrieves values over the specified time range suitable for plotting over the number of intervals (typically represents pixels).

Remarks

For each interval, the data available is examined and significant values are returned. Each interval can produce up to 5 values if they are unique, the first value in the interval, the last value, the highest value, the lowest value and at most one exceptional point (bad status or digital state). 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}/plot

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. 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.

• intervals

  The number of intervals to plot over. Typically, this would be the number of horizontal pixels in the trend. The default is '24'. For each interval, the data available is examined and significant values are returned. Each interval can produce up to 5 values if they are unique, the first value in the interval, the last value, the highest value, the lowest value and at most one exceptional point (bad status or digital state).

• 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.

• 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 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": {}
}