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Owning Palette: Historical VIs

Installed With: DSC Module

Computes statistical data for a historical trace.

Details  

	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.
	time on is the amount of time for which data has a nonzero value in the trace. This value applies only to discrete shared variables.
	quality is the ratio of time that the trace has had known values to the total time elapsed in the trace. This value applies only to discrete shared variables.
	max value is the maximum value in the historical trace. This output ignores invalid points (value = NaN).
	min value is the minimum value in the historical trace. This output ignores invalid points (value = NaN).
	average is the average for the values in the historical trace. This is a weighted average. Each point is weighted according to its time duration. average ignores time intervals with invalid points (value = NaN). The last point in the trace is not included in average because there is no known time interval associated with it.
	standard deviation is the standard deviation for values in the historical trace. This is a weighted standard deviation. Each point is weighted according to its time duration. standard deviation ignores time intervals with invalid points (value = NaN). The last point in the trace is not included in the standard deviation because there is no known time interval associated with it.
	# stops is the number of times the data value transitions from on to off in the trace. This value applies only to discrete shared variables.
	# starts is the number of times the data value transitions from off to on in the trace. This value applies only to discrete shared variables.

Get Trace Statistics Details

Statistics include max value, min value, average, and standard deviation. The statistics skip invalid input points where value = NaN. average and standard deviation are weighted according to the time duration of each valid input point. The last point in the historical trace is not included in average and standard deviation because the time interval associated with it is unknown.