Applies Nelson tests to the input points array. Given a set of control chart points and the center line and std error from the control chart computations, this VI will check whether points are out of control (or non-randomly distributed) according to the Nelson tests enabled. The front panel below shows which tests can be enabled. The tests that are violated along with the first point and length of the sequence of points are output.


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Inputs/Outputs

  • c1ddbl.png points —

    points contains the points plotted on the control chart, which normally is the output of one of the control chart VIs, such as an x-bar array.

  • cdbl.png center line —

    (DBL) - the center line from the control chart.

  • cdbl.png std error —

    (DBL) - the standard error associated with the center line (CL) from the control chart.

  • c1dbool.png test enable —

    test enable contains the run rules to apply to the points array. Each element of the array corresponds to a test 1, 2, 3, … 8 from element 0 to 7, in that order (see front panel for test explanation). Set the corresponding element to TRUE for each test you want to apply. (An easy way to do this from the diagram is to use an unsigned 8-bit integer, set the appropriate bits, and then use the number to binary array conversion.)

  • i1dcclst.png tests flagged —

    tests flagged lists the tests violated and which sequence of points violated the test.

  • istr.png Test —

    tests flagged lists the tests violated and which sequence of points violated the test.

  • ii32.png first point —

    tests flagged lists the tests violated and which sequence of points violated the test.

  • ii32.png run length —

    tests flagged lists the tests violated and which sequence of points violated the test.

  • i1di32.png out of control points —

    points contains the points plotted on the control chart, which normally is the output of one of the control chart VIs, such as an x-bar array.