WEIBULL

WEIBULL(x, alpha, beta, cumulative)

Returns the probability distribution function OR the cumulative probability function for a weibull distribution.

x	The numeric value at which to evaluate the function.
alpha	The first parameter.
beta	The second parameter.
cumulative	A logical value indicating the type of function to use: False (or 0) = individual probability (equal to) True (<> 0) = cumulative probability (equal to or less than)

REMARKS

* WEIBULL.DIST was added in Excel 2010 to replace this function.
* This function is only available for backwards compatibility and should not be used.
* The weibull distribution is a continuous distribution
* If "x", is nonnumeric, then #VALUE! is returned.
* If "x" < 0, then #NUM! is returned.
* 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.
* If "cumulative" = False, then the height of the curve at "x" is returned.
* If "cumulative" = True, then the area under the curve to the left of "x" 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
4	=WEIBULL(0, 1, 2, 3) = 0.000