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Owning Palette: Historical VIs

Installed With: DSC Module

Decimates, or resamples, historical trace data from the start timestamp to the stop timestamp.

The decimated trace output is a 1D array of the value at each time interval from the first timestamp to the last timestamp.

	sample interval determines the time interval for each historical trace. If you do not wire this parameter, the data is sampled at 1 second intervals.
	check start/stop time? determines whether the requested start and stop times are checked against data available in the historical trace. If this parameter is TRUE, the VI checks the start and stop timestamps against the first and last timestamps in the historical trace. The first/last timestamp in the trace is used instead of any requested start/stop time out of the range of the trace. To override this and use the input values regardless of the data points in the trace, set this parameter to FALSE.
	historical trace is the historical trace passed into the VI. timestamps is the date and time for the data points in the data array. data is the data logged for the shared variable at the corresponding timestamp. This input can be a numeric or bit array data type.
	start timestamp is the start date and time of data you want to retrieve from the database. The LabVIEW Datalogging and Supervisory Control (DSC) Module retrieves the entire page on which the data appears. When you view the data, you might see data logged before the actual time you specified.If you do not wire this input, the DSC Module uses the timestamp of the first data point in the database.
	stop timestamp is the end date and time of data you want to retrieve from the database. The DSC Module retrieves the entire page on which the data appears. When you view the data, you might see data logged after the actual time you specified.If you do not wire this input, the DSC Module uses the timestamp of the last data point in the database.
	error in describes error conditions that occur before this VI or function runs. The default is no error. If an error occurred before this VI or function runs, the VI or function passes the error in value to error out. This VI or function runs normally only if no error occurred before this VI or function runs. If an error occurs while this VI or function runs, it runs normally and sets its own error status in error out. Use the Simple Error Handler or General Error Handler VIs to display the description of the error code. Use error in and error out to check errors and to specify execution order by wiring error out from one node to error in of the next node. status is TRUE (X) if an error occurred before this VI or function ran or FALSE (checkmark) to indicate a warning or that no error occurred before this VI or function ran. The default is FALSE. code is the error or warning code. The default is 0. If status is TRUE, code is a nonzero error code. If status is FALSE, code is 0 or a warning code. source specifies the origin of the error or warning and is, in most cases, the name of the VI or function that produced the error or warning. The default is an empty string.
	decimated trace is a list of historical trace values starting at first timestamp. Each trace value is sample interval seconds apart. value is the value of the decimated trace. The value can be a numeric or bit array data type.
	first timestamp is the date and time associated with the first data point retrieved from the historical database.
	last timestamp is the date and time associated with the last data point retrieved from the historical database.
	error out contains error information. If error in indicates that an error occurred before this VI or function ran, error out contains the same error information. Otherwise, it describes the error status that this VI or function produces. Right-click the error out front panel indicator and select Explain Error from the shortcut menu for more information about the error. status is TRUE (X) if an error occurred or FALSE (checkmark) to indicate a warning or that no error occurred. code is the error or warning code. If status is TRUE, code is a nonzero error code. If status is FALSE, code is 0 or a warning code. source describes the origin of the error or warning and is, in most cases, the name of the VI or function that produced the error or warning.