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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 sigma, creates a graph of a normal probability distribution function (PDF) of the process and a vertical bar graph centered at each of the bin centers x[] 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 the display mode is not wired, the specification limits and natural process limits (at 3 sigma) is drawn by default.

	PDF height is the height to draw the PDF. If 0, the PDF will be drawn with a height proportional to 1/sigma - corresponding to an area of 1 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.
	PDF width (+/- sigma) is the width to draw the PDF in terms of +/- sigma. If unwired, the PDF is drawn from - 3 sigma to + 3 sigma.
	# points to plot for PDF (50) is the number of points to make up the PDF plot. You can normally leave this unwired.
	bin centers/axis x[] contains the x-axis values for the center of each histogram bin. Connect the axis output of the General Histogram VI to this input.
	histogram y[] contains the number of observations in each bin of the histogram from left to right for each element of this array. Connect the histogram output from the General Histogram VI to this input.
	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 Process Mean & Sigma VI or Sample Statistics VI for an explanation of how the process mean and process sigma are calculated.
	process sigma is the estimated process sigma. See the Process Mean & Sigma VI or Sample Statistics VI.
	display mode (T,T,3) is an optional display mode specifier. If unwired, the specification limits and the natural process limits will be drawn by default. show spec limits specifies whether the specification limits are drawn. The default is TRUE. 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 3. The natural process limits drawn will then be process mean +/- NPLimit sigma*process sigma.
	Histogram and Normal PDF Graph is a graph with the normal PDF of the process plotted against the specification limits and process mean and standard deviation. This is also known as a process capability plot.