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Writes a single data point to a Citadel trace.

You must select the polymorphic instance of this VI that matches the type of the Open Trace VI you used to create the input refnum.

This VI returns an error if you try to write a point with a timestamp that is earlier than the timestamp of the last point written to the trace.

Use the pull-down menu to select an instance of this VI.

Select an instanceWrite Trace (Numeric)Write Trace (Logical)Write Trace (String)Write Trace (Bit Array)Write Trace (Variant)

Write Trace (Numeric)

	trace reference is the refum to the trace being written. Only references created by the Open Trace (Numeric) VI are valid.
	value is the value to write to the database.
	timestamp is the timestamp associated with value. Leave this input unwired to associate the current time with this value. Note  The Read Trace VI returns data breaks as a default value with a 0 timestamp. If you want to use the Read Trace and Write Trace VIs to copy Citadel data, do not wire the output of the Read Trace VI directly to the input of the Write Trace VI. Instead, detect any 0 timestamps in the Read Trace VI output and use the Write Trace Break VI to log data breaks correctly. Consider using the Archive Traces VI to copy Citadel data more efficiently.
	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.
	trace reference dup is the same value as trace reference.
	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 Trace (Logical)

	trace reference is the reference for the trace being written. Only references created by the Open Trace (Logical) VI are valid.
	value is the value to write to the database.
	timestamp is the timestamp associated with value. Leave this input unwired to associate the current time with this value. Note  The Read Trace VI returns data breaks as a default value with a 0 timestamp. If you want to use the Read Trace and Write Trace VIs to copy Citadel data, do not wire the output of the Read Trace VI directly to the input of the Write Trace VI. Instead, detect any 0 timestamps in the Read Trace VI output and use the Write Trace Break VI to log data breaks correctly. Consider using the Archive Traces VI to copy Citadel data more efficiently.
	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.
	trace reference dup is the same value as trace reference.
	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 Trace (String)

	trace reference is the reference for the trace being written. Only references created by the Open Trace (String) VI are valid.
	value is the value to write to the database.
	timestamp is the timestamp associated with value. Leave this input unwired to associate the current time with this value. Note  The Read Trace VI returns data breaks as a default value with a 0 timestamp. If you want to use the Read Trace and Write Trace VIs to copy Citadel data, do not wire the output of the Read Trace VI directly to the input of the Write Trace VI. Instead, detect any 0 timestamps in the Read Trace VI output and use the Write Trace Break VI to log data breaks correctly. Consider using the Archive Traces VI to copy Citadel data more efficiently.
	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.
	trace reference dup is the same value as trace reference.
	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 Trace (Bit Array)

	trace reference is the reference for the trace being written. Only references created by the Open Trace (Bit Array) VI are valid.
	value is the value to write to the database.
	timestamp is the timestamp associated with value. Leave this input unwired to associate the current time with this value. Note  The Read Trace VI returns data breaks as a default value with a 0 timestamp. If you want to use the Read Trace and Write Trace VIs to copy Citadel data, do not wire the output of the Read Trace VI directly to the input of the Write Trace VI. Instead, detect any 0 timestamps in the Read Trace VI output and use the Write Trace Break VI to log data breaks correctly. Consider using the Archive Traces VI to copy Citadel data more efficiently.
	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.
	trace reference dup is the same value as trace reference.
	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 Trace (Variant)

	trace reference is the reference for the trace being written. Only references created by the Open Trace (Variant) VI are valid.
	value is the value to write to the database.
	timestamp is the timestamp associated with value. Leave this input unwired to associate the current time with this value. Note  The Read Trace VI returns data breaks as a default value with a 0 timestamp. If you want to use the Read Trace and Write Trace VIs to copy Citadel data, do not wire the output of the Read Trace VI directly to the input of the Write Trace VI. Instead, detect any 0 timestamps in the Read Trace VI output and use the Write Trace Break VI to log data breaks correctly. Consider using the Archive Traces VI to copy Citadel data more efficiently.
	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.
	trace reference dup is the same value as trace reference.
	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.