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Owning Palette: Process Statistics VIs

Installed With: Statistical Process Control Toolkit

Computes process mean and sigma and upper and lower natural process limits from process samples. You can estimate the process sigma in several ways. If the sample size is greater than one, you can use either sample standard deviation s or range R to estimate the process sigma. You select s or R by the type input. If the sample size is one, the VI automatically uses the moving range to estimate the process sigma.

	samples X specifies the samples on which to compute process mean and process sigma. Each row is a sample with n observations where n is the number of columns in the 2D array. To calculate process mean and sigma on a 1D array, use the array builder primitive to create a 2D array and then wire to the samples X input.
	type: s/R (s) is the type of process sigma computation to perform. Note  If sample size is 1, process sigma estimate is based on mean moving range. R base process sigma estimate on mean sample range s base process sigma estimate on mean sample standard deviation (default)
	n for moving Range (2) is ignored unless the sample size (number of columns) in the input array samples X is one, in which case the moving range is used as a basis for estimating process mean and sigma. n for moving Range ranges from 2 to 25. By default, n for moving Range is set to 2.
	sigma multiplier (3) is the sigma multiplier for calculating upper NPL and lower NPL. By default, sigma is multiplied by 3.0.
	process mean is the mean of the process, estimated from X-bar-bar (or x-bar if sample size is one).
	process sigma is the sigma of the process, estimated from if type is S, if type is r, or if sample size is 1.
	upper NPL is the upper natural process limit of the process computed as process mean + sigma multiplier * process sigma. By default, this is process mean + 3.0 * process sigma.
	lower NPL is the lower natural process limit of the process computed as process mean - sigma multiplier * process sigma. By default, this is process mean - 3.0 * process sigma.