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Owning Palette: Process Statistics Graphing VIs

Installed With: Statistical Process Control Toolkit

Given the specification limits and the process mean and process sigma, creates a graph of a normal probability distribution function (PDF) of the process against the specification limits and process mean and sigma.

You can turn on and off drawing of the specification limits or the natural process limits, and specify the sigma multiplier to use for the natural process limits (default 3), by wiring in the display mode. If you do not wire the display mode, the VI automatically draws the specification limits and natural process limits.

	# PDF points to plot (50) is the number of points to create for the normal PDF plot. In most cases, you can leave this unwired. By default 50 points are plotted.
	PDF width (+/- sigma) is the width to draw the PDF in terms of ± sigma. If unconnected, the VI draws the PDF from –3 sigma to +3 sigma by default.
	PDF height is the height to draw the PDF. If zero, the VI will draw the PDF with a height proportional to 1/(process sigma), corresponding to an area of one under the PDF curve. When fitting a normal PDF to a histogram, use the PDF height output from the Fit Nrml PDF to Histogram VI.
	upper spec limit is the upper specification limit of the process.
	lower spec limit is the lower specification limit of the process.
	process mean is the estimated process mean. See the description of the Process Mean & Sigma VI for an explanation of how the process mean and process sigma are calculated.
	process sigma is the estimated process sigma.
	display mode (T,T,3) is an optional display mode specifier. If you do not wire this cluster, the specification limits and the natural process limits will be drawn by default. This cluster contains the following inputs. Note  If you wire the display mode cluster to change one of the default settings, you must specify all three elements. show spec limits specifies whether to draw the specification limits. show natural process limits specifies whether the natural process limits are drawn on the plot. The default is TRUE. NP limit sigma is the sigma multiplier for the natural process limits. By default, this is three. The natural process limits drawn will then be process mean ±NP limit sigma * process sigma.
	normal PDF graph with limits returns an XY graph with the normal PDF of the process plotted against the specification limits and process mean and standard deviation.