WorksheetFunction.Weibull_Dist Method (Excel)
Returns the Weibull distribution. Use this distribution in reliability analysis, such as calculating the mean time to failure for a device.
Version Information
Version Added: Excel 2010
Syntax
expression .Weibull_Dist(Arg1, Arg2, Arg3, Arg4)
expression A variable that represents a WorksheetFunction object.
Parameters
Name |
Required/Optional |
Data Type |
Description |
---|---|---|---|
Arg1 |
Required |
Double |
X - The value at which to evaluate the function. |
Arg2 |
Required |
Double |
Alpha - A parameter to the distribution. |
Arg3 |
Required |
Double |
Beta - A parameter to the distribution. |
Arg4 |
Required |
Boolean |
Cumulative - Determines the form of the function. |
Return Value
Double
Remarks
If x, alpha, or beta is non-numeric, WEIBULL_DIST returns the #VALUE! error value.
If x < 0, WEIBULL_DIST returns the #NUM! error value.
If alpha ≤ 0 or if beta ≤ 0, WEIBULL_DIST returns the #NUM! error value.
The equation for the Weibull cumulative distribution function is:
The equation for the Weibull probability density function is:
When alpha = 1, WEIBULL_DIST returns the exponential distribution with: