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aBook Page 19 Wednesday, April 22, 1998 8:21 AM
Chapter 2
Control Chart VIs
index spec. Use this cluster to choose a range of individuals to use for
control limits calculation.
start index. Index of the first individual to include in the
control limit calculation. Default is zero or index of the first
individual in individuals x array.
end index. Index of the last individual to include in the
control limit calculation. Default is zero which selects the
last sample in individuals x array.
If you do not wire this cluster, all values in individuals x input array are
included in the control limit calculation.
indices to ignore. Indices of individuals to exclude from the control limit
calculation. This is useful for eliminating out-of-control points from the
control limit calculation. By default, this is an empty array.
std error multiplier. The multiplier to use for the upper and lower
control limits. Normally you leave std error multiplier unwired, and the
VI sets the control chart limits to +/- 3.0 standard errors. The default is
3.0.
x-bar-bar. This is an estimate of the process mean based on the moving
average of the individuals included in the control limit calculation. If the
control limits are calculated from standard values, this is set to the
standard mean.
moving Average mX-bar. The moving average of individuals
{x[i], ...., x[i-n+1]}, where n is the sample size. This is the array plotted
on the x control chart.
mX-bar chart limits. This cluster contains the limits for the moving
average chart.
UCLmx. The upper control limit for the moving average
chart.
CLmx. The center line for the x control chart. Clmx = xbar-bar or standard mean and is also the estimated process
mean if calculated from the input individuals.
LCLmx. The lower control limit for the moving average
chart.
standard error. The standard error associated with CLmx.
© National Instruments Corporation
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LabVIEW SPC Toolkit Reference Manual