Click or drag to resize
OSIsoft, LLC

AFDataInterpolatedValues Method

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

Namespace:  OSIsoft.AF.Data
Assembly:  OSIsoft.AFSDK (in OSIsoft.AFSDK.dll) Version:
public AFValues InterpolatedValues(
	AFTimeRange timeRange,
	AFTimeSpan interval,
	UOM desiredUOM,
	string filterExpression,
	bool includeFilteredValues


Type: OSIsoft.AF.TimeAFTimeRange
The bounding time range for the interpolated values request. If the StartTime is earlier than the EndTime, the resulting values will be in time-ascending order, otherwise they will be in time-descending order.
Type: OSIsoft.AF.TimeAFTimeSpan

The Sample interval. If specified in hours, minutes, seconds, or milliseconds, the time intervals will be evenly spaced UTC time intervals. Longer interval types are interpreted using wall clock rules and are time zone dependent. For example, an interval created with the string "24h" means using an evenly spaced 24 UTC hour interval between each event. On the other hand, an interval created with the string "1d" would return an interval shorter or longer than 24 hours if the interval encompasses a Daylight Savings Time change.

When a positive interval is specified, the interval calculation begins at the earliest bounding time in the timeRange and applies the interval repeatedly in time ascending direction to generate the calculation intervals.

If a negative interval is specified, the interval calculation begins at the latest bounding time in the timeRange and applies the interval repeatedly in time descending direction to generate the calculation intervals. Note that the order of values returned will still be reflected by the timeRange, regardless of the interval sign.

Type: OSIsoft.AF.UnitsOfMeasureUOM
The desired unit of measure for the returned values. If , then the values are returned in the unit of measure specified by the associated attribute's DefaultUOM property.
Type: SystemString
A string containing a filter expression. Expression variables are relative to the attribute. Use '.' to reference the containing attribute. A or empty string indicates no filtering. If the attribute does not support the Filters option, the filter will be ignored.
Type: SystemBoolean
Specify 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.

Return Value

Type: AFValues
Returns an AFValues collection with the interpolated values.
NotSupportedException The data reference does not support the this method, or the configured data reference does not support filter expressions and one was provided.
The following table illustrates the interaction between timeRange and interval with the timestamp interval calculations and order of returned values:
Time RangeIntervalTimestamps returned in AFValues
Ascending (Y to T)Positive (5h)Y, Y+5h, Y+10h, Y+15h, Y+20h
Descending (T to Y)Positive (5h)Y+20h, Y+15h, Y+10h, Y+5h, Y
Ascending (Y to T)Negative (-5h)T-20h, T-15h, T-10h, T-5h, T
Descending (T to Y)Negative (-5h)T, T-5h, T-10h, T-15h, T-20h

Note Notes to Callers
This method, property, or class is only available in the .NET 4 version of the SDK.

Security note Security Note
You must have ReadData security rights to read a data value.

Version Information


Supported in: 2.10.5, 2.10, 2.9.5, 2.9, 2.8.5, 2.8, 2.7.5, 2.7, 2.6, 2.5
See Also
Enabling Operational Intelligence