WorksheetFunction.Weibull(Double, Double, Double, Boolean) Method

Reference

Definition

Namespace:: Microsoft.Office.Interop.Excel

Assembly:: Microsoft.Office.Interop.Excel.dll

Important

Some information relates to prerelease product that may be substantially modified before it’s released. Microsoft makes no warranties, express or implied, with respect to the information provided here.

Returns the Weibull distribution. Use this distribution in reliability analysis, such as calculating a device's mean time to failure.

public:
 double Weibull(double Arg1, double Arg2, double Arg3, bool Arg4);

public double Weibull (double Arg1, double Arg2, double Arg3, bool Arg4);

Public Function Weibull (Arg1 As Double, Arg2 As Double, Arg3 As Double, Arg4 As Boolean) As Double

Parameters

Arg1: Double

X - the value at which to evaluate the function.

Arg2: Double

Alpha - a parameter to the distribution.

Arg3: Double

Beta - a parameter to the distribution.

Arg4: Boolean

Cumulative - determines the form of the function.

Returns

Double

Remarks

Important: This function has been replaced with one or more new functions that may provide improved accuracy and whose names better reflect their usage. This function is still available for compatibility with earlier versions of Excel. However, if backward compatibility is not required, you should consider using the new functions from now on, because they more accurately describe their functionality. For more information about the new function, see the Weibull_Dist(Double, Double, Double, Boolean) method.

If x, alpha, or beta is nonnumeric, Weibull returns the #VALUE! error value. If x < 0, Weibull returns the #NUM! error value.

If alpha ≤ 0 or if beta ≤ 0, Weibull returns the #NUM! error value.

The equation for the Weibull cumulative distribution function is:

Figure 1: Equation for the Weibull cumulative distribution

The equation for the Weibull probability density function is:

Figure 2: Equation for the Weibull probability density

When alpha = 1, Weibull returns the exponential distribution with:

Figure 3: Equation

Applies to