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Owning Palette: Control Charts VIs

Installed With: Statistical Process Control Toolkit

Computes single points for the x and moving range or moving average and moving range control charts. Computing single points is useful for plotting control charts one point at a time while you are collecting samples. You must still use the x & mR Chart or mX-bar & mR Chart VIs to calculate the control limits for the chart. This VI is reentrant so that you can use multiple copies. Each time it is called, this VI saves a copy of the previous n-1 individuals to use in calculating the next moving Average and Range.

	individual x is the sample on which to compute the control chart points. The sample contains two or more individual observations.
	n: sample size (2) is the sample size to use for the moving average and moving range calculations. n: sample size ranges from 2 to 25. By default, sample size is 2.
	first point (F) initializes the VI. first point should be TRUE for the first point, FALSE afterwards. The VI calculates the first point moving Range mR as zero.
	individual x creates an X control chart when you wire this output to the waveform chart.
	moving Average mX-bar is the average of the current individual x and the previous sample size n-1 individual x values. Wire this output to the waveform chart to create a moving average control chart.
	moving Range mR is the range of the current individual x and the previous sample size n-1 individual x values. Wire this output to the waveform chart to create a moving range control chart.
	valid mX-bar/mR, when set to TRUE, calculates the moving Average and Range when the VI has accumulated sample size n points. For example, for sample size n = 2, the VI must be called twice to accumulate 2 individual x values from which to calculate the moving average and range. Until sample size n values are accumulated, the moving average and range are calculated from a smaller sample size, and valid mX-bar/mR is set to FALSE.