IMSL C# Chart Guide: CuSum

IMSL C# Programmer’s Guide

Quality Control and Improvement Charts >> CuSum

CuSum

CuSum is the cumulative sum control chart. It plots the cumulative sum of the deviations of the expected value. If is the expected mean for a process and are the sample means then the cumulative sum is

CuSum Example

The data used is the same as for the EWMA example.

(Download Code)

using Imsl.Chart2D;
using Imsl.Chart2D.QC;

public class SampleCuSum : FrameChart {
    static double[] data = {
        9.45, 7.99, 9.29, 11.66, 12.16, 10.18, 8.04, 11.46, 9.20, 10.34, 9.03,
        11.47, 10.51, 9.40, 10.08, 9.37, 10.62, 10.31, 8.52, 10.84, 10.90,
        9.33, 12.29, 11.50, 10.60, 11.08, 10.38, 11.62, 11.31, 10.52
    };

    public SampleCuSum() {
        Chart chart = this.Chart;
        AxisXY axis = new AxisXY(chart);
        CuSum cusum = new CuSum(axis, data);
        cusum.ExpectedMean = 10.0;

        axis.AxisX.AxisTitle.SetTitle(“Sample Number”);
        axis.AxisX.AxisLabel.TextFormat = “0”;
        axis.AxisY.AxisTitle.SetTitle(“CuSum”);
    }

    public static void Main(string[] argv) {
        System.Windows.Forms.Application.Run(new SampleCuSum());
    }
}