Computes points and limits for a c Chart - a control chart for number of defects or non-conformities per unit sample. A range of indices for samples to be used and indices to ignore in the control calculation can also be specified. The actual number of samples used to calculate the control limits is supplied. FORMULAS: c-bar = c / (c array length) UCLc = c-bar+ stderr mult x sqrt(c-bar) CLc = c-bar LCLnp = c-bar - stderr mult x sqrt(c-bar) standard error = sqrt(c-bar)


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Inputs/Outputs

  • cnclst.png chart limit src —

    (Optional) Specifier for source of chart limit calculation. NOTE: this defaults to the most generally used case, where the chart limits are calculated from the data. You do not have to wire this cluster unless you want the chart limits calculated from standard values. Cluster of: Source (I16) - two choices for soure of chart limits calculation 0: from data - chart limits are calculated from data (default selection) 1: std c0 - chart limits are calculated from standard given c0. std c0 (DBL) - in case of standard given, the standard c0 to use in calculating chart limits.

  • cenum.png source —

    (U16) - two choices for source of chart limits calculation 0: from data - chart limits are calculated from data (default selection) 1: std c0 - chart limits are calculated from standard given c0.

  • cdbl.png std c0 —

    (DBL) - in case of standard given, the standard c0 to use in calculating chart limits.

  • c1ddbl.png c:# defects/sample —

    c:# defects/sample is the number of non-conformities or defects per sample inspected.

  • cdbl.png std error multiplier (3) —

    (DBL, default = 3.0). Ordinarily you would leave this unwired and the control chart limits are computed as +/- 3.0 standard errors.

  • cnclst.png index spec —

    (optional) cluster of: start index (I32) - index of the first element of cto include in the control limit calculation. Default is 0 or index of the first sample in the c array. end index (I32) - index of the last element of c to include in the control limit calculation. Default is 0 which selects the last sample in c array. If this cluster is unwired, all elements in c input array are included in the control limit calculation.

  • ci32.png start index —

    (I32) - index of the first element of r to include in the control limit calculation. Default is 0 or index of the first sample in the c array.

  • ci32.png end index —

    (I32) - index of the last element of c to include in the control limit calculation. Default is 0 which selects the last sample in the c array.

  • c1di32.png indices to ignore —

    indices to ignore defines the indices of c 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.

  • ii32.png # samples in calc —

    (I32) - the number of samples used in the control limits calculation.

  • i1ddbl.png c:# non-conformities/inspection unit —

    c:# non-conformities/inspection unit is the number of non-conformities or defects found per sample unit, which is identical to the input array c. These are the points plotted on the c control chart.

  • inclst.png c chart limits —

    cluster of: UCLc (DBL) - the upper control limit for the c chart. If std error multiplier is 3, this will be c-bar + 3 standard errors. CLc (DBL) - the center line c-bar for the c control chart. c-bar is the estimated number of non-conformities for the process. LCLc (DBL) - the lower control limit for the c chart. If std error multiplier is 3, this will be np-bar - 3 standard errors. standard error (DBL) - the standard error associated with c-bar.

  • idbl.png UCLc —

    (DBL) - the upper control limit for the c chart. If std error multiplier is 3, this will be c-bar + 3 standard errors.

  • idbl.png c-bar —

    (DBL) - the center line c-bar for the c control chart. c-bar is the estimated number of non-conformities for the process.

  • idbl.png LCLc —

    (DBL) - the lower control limit for the c chart. If std error multiplier is 3, this will be np-bar - 3 standard errors.

  • idbl.png standard error —

    (DBL) - the standard error associated with c-bar.

    • c Chart Details

    , if calculated from the input data, otherwise