/// <summary>
/// 计算Xbar-R图控制线
/// </summary>
/// <param name="xTotalAvg">总平均值</param>
/// <param name="rTotalAvg">平均极差值</param>
/// <param name="n">平均子组数量</param>
/// <returns>返回：X管制上线、X管制中线、X管制下线、R管制上线、R管制中线、R管制下线</returns>
public static IDictionary CalculateXbar_RControlLine(double xTotalAvg, double rTotalAvg, int n)
{
double d2 = 0, d3 = 0;
d2 = new ConstantSPC("D2").GetConstantItem(n).Value;
d3 = new ConstantSPC("D3").GetConstantItem(n).Value;
Dictionary <string, double> xbarRCtrlLineDic = new Dictionary <string, double>();
double xCL = 0, xUCL = 0, xLCL = 0;
double rCL = 0, rUCL = 0, rLCL = 0;
//double A2 = 0;
double D3 = 0;
double D4 = 0;
double eValue = 0;
xCL = Math.Round(xTotalAvg, 4);
rCL = Math.Round(rTotalAvg, 4);
eValue = rTotalAvg / (Math.Sqrt(n) * d2);
xUCL = Math.Round(xTotalAvg + 3 * eValue, 4);
xLCL = Math.Round(xTotalAvg - 3 * eValue, 4);
D3 = 1 - 3 * d3 / d2;
D4 = 1 + 3 * d3 / d2;
rUCL = Math.Round(D4 * rTotalAvg, 4);
rLCL = Math.Round(D3 * rTotalAvg < 0 ? 0 : D3 * rTotalAvg, 4);
xbarRCtrlLineDic.Add("xCL", xCL);
xbarRCtrlLineDic.Add("xUCL", xUCL);
xbarRCtrlLineDic.Add("xLCL", xLCL);
xbarRCtrlLineDic.Add("rCL", rCL);
xbarRCtrlLineDic.Add("rUCL", rUCL);
xbarRCtrlLineDic.Add("rLCL", rLCL);
xbarRCtrlLineDic.Add("eValue", eValue);
return(xbarRCtrlLineDic);
}
/// <summary>
/// 计算XBAR-S 的管制线
/// </summary>
/// <param name="xTotalAvg">样本总平均值</param>
/// <param name="avgS">样本标准差</param>
/// <param name="C4"></param>
/// <param name="n"></param>
/// <returns></returns>
public static IDictionary CalculateXbar_SControlLine(double xTotalAvg, double avgS, int n)
{
double C4 = 0;
C4 = new ConstantSPC("C4").GetConstantItem(n).Value;
Dictionary <string, double> xbarSCtrlLineDic = new Dictionary <string, double>();
double xCL = 0, xUCL = 0, xLCL = 0;
double sCL = 0, sUCL = 0, sLCL = 0;
double A3 = 0, B3 = 0, B4 = 0, tempValue = 0;
double eValue = 0; //sigma
xCL = Math.Round(xTotalAvg, 4);
sCL = Math.Round(avgS, 4);
//eValue = avgS / (Math.Sqrt(Convert.ToDouble(n)) * C4);
//计算Sigma
eValue = avgS / C4;
A3 = 3 / (Math.Sqrt(Convert.ToDouble(n)) * C4);
tempValue = (Math.Sqrt(1 - Math.Pow(C4, 2))) / C4;
B3 = 1 - 3 * tempValue;
B4 = 1 + 3 * tempValue;
xUCL = Math.Round(xTotalAvg + A3 * avgS, 4);
xLCL = Math.Round(xTotalAvg - A3 * avgS, 4);
sUCL = Math.Round(B4 * avgS, 4);
sLCL = Math.Round(B3 * avgS, 4);
xbarSCtrlLineDic.Add("xCL", xCL);
xbarSCtrlLineDic.Add("xUCL", xUCL);
xbarSCtrlLineDic.Add("xLCL", xLCL);
xbarSCtrlLineDic.Add("sCL", sCL);
xbarSCtrlLineDic.Add("sUCL", sUCL);
xbarSCtrlLineDic.Add("sLCL", sLCL);
xbarSCtrlLineDic.Add("eValue", eValue);
return(xbarSCtrlLineDic);
}
