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Owning Palette: Historical VIs

Installed With: DSC Module

Stores the data from a set of historical trends into a spreadsheet file.

Details  

	timeout limits the time that the VI waits for data to be returned from the database. The default value is 30 seconds. A timeout value of less than or equal to 0 indicates no timeout, and the VI waits indefinitely until the data is returned. The VI ignores this value if you set show status bar to TRUE.
	formatting information contains inputs that determine the format of the spreadsheet. Refer to the Details section for information about formatting the spreadsheet. header text is the text to display in the column header. footer text is the text that appears at the bottom of the spreadsheet file. delimiter is the separator used in the spreadsheet format. The default is a tab. You also can choose to delimit the columns of the spreadsheet with commas, semicolons, spaces, or pipes. Pipes are the characters entered when you press the <Shift–\> keys. row format is the format of the rows of the spreadsheet.
	trace information contains timestamp and sample interval information about the trace(s). time interval is the span of time between the start timestamp and stop timestamp. If you do not wire this input, the VI reads all data logged up to now. 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. 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.
	database URL is the computer name and the database name where the Citadel database resides. Enter the database URL in the format \\computer\database_name. For example, if you have a copy of the LabVIEW Datalogging and Supervisory Control (DSC) Module and Citadel service installed on a computer named datalogger and the name of the database on that computer is data, you can access the data on datalogger from another computer by using the path \\datalogger\data. If you provide a database name only, the DSC Module searches for the database on the local computer. If you do not wire database URL, the VI reads data from the database associated with the default DSC Module process.
	trace names specifies the list of historical traces for which you want to read historical data. You can specify either Shared Variable references or existing traces for this parameter. The DSC Module uses these trace names as column headers when you convert this information into spreadsheet format.
	output file path is the full path to the spreadsheet file to be created.
	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.
	show status bar enables a progress bar during the operation if show status bar is TRUE.
	database URL out returns the computer name and the database name to specify where the Citadel database resides. The format is \\computer\database_name.
	output file path out returns the full path to the spreadsheet file.
	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.

Write Traces to Spreadsheet File Details

This VI creates a column header that labels the date, time, and trace names. The default delimiter is the tab character. You can designate a different value, such as a comma by using the formatting information parameter to change the character used to separate columns.

The following variables are variables that you can apply to the entire export file to customize the spreadsheet. Enter these variables in the header text, footer text, or row format parameters.

Variable	Description
creationDate	Date that exported file is created.
creationTime	Time that exported file is created.
delimiter	The delimiter is specified by the delimiter parameter.
endDate	End date specified by the stop timestamp parameter value in the formatting information control.
endTime	End time specified by the stop timestamp parameter value in the formatting information control.
interpType	Reports the type of interpolation.
name [N]	N=[0...numTraces). Name of trace N. Traces are indexed by number, starting with 0, in the order they appear in the trace names parameter. The fourth trace, for instance would be represented by name[3].
numTraces	Number of traces in the trace names parameter.
repeat(N,X,Y,"S")	Use this variable to repeat other variables so that the format template can be used with trace views that have different numbers of traces.
rows	Number of total rows of data exported.
startDate	Start date specified in the start timestamp parameter value in the formatting information control.
startTime	Start time specified in the start timestamp parameter value in the formatting information control.
timeInterval	Interpolation time interval specified in the sample interval control.

The following variables are variables that you can apply to the row format parameter to customize the rows of the spreadsheet.

Variable	Description
date	Date of current row
quality[N]	Quality of trace N. 0= good quality and other numeric values indicate bad quality.
row	Row number
signals[N]	type signal for trace N 0= asynchronous 1= synchronous
time	Time of current row
value[N]	N=[0...numTraces]. Value of the N trace in the current row.