Excel Function WEIBULL

WEIBULL(x, alpha, beta, cumulative)

Returns the probability of getting less than or equal to a particular value in a weibull distribution.

x	The numeric value at which to evaluate the function.
alpha	The first parameter.
beta	The second parameter.
cumulative	The type of function to use True = cumulative probability function False = probability mass function

Remarks

* WEIBULL.DIST was added in Excel 2010 to replace this function.
* The Weibull distribution is a continuous distribution.
* If "x", is nonnumeric, then #VALUE! is returned.
* If "x" < 0, then #NUM! is returned.
* If "x" = 0, then ??
* If "alpha" = 0, then #NUM! is returned.
* If "alpha" is nonnumeric, then #VALUE! is returned.
* If "beta" = 0, then #NUM! is returned.
* If "beta" is nonnumeric, then #VALUE! is returned.
* This function can be used in reliability analysis, such as calculating a device's mean time to failure.
* For the Microsoft documentation refer to support.microsoft.com

	A
1	=WEIBULL(105,20,100,TRUE) = 0.930
2	=WEIBULL(105,20,100,FALSE) = 0.036
3	=WEIBULL(5,1,2,3) = 0.918