3.5.3.1.12 FcdfFcdf-func
Description
Computes cumulative distribution function at f, with parameters ndf, fdf, and tail. The parameters of ndf and fdf must all be positive, and the values in f must be positive. The parameter tail determines the returned probability is the lower tailed or upper tailed.
The result, prob, is the probability that a single observation from a distribution with parameters ndf and fdf will fall in the interval [0, f] for lower-tailed, [f, ] for upper-tailed.
Syntax
double prob = fcdf(double f, double ndf, double fdf[, int tail])
Parameters
f
- Input, the value of the variate,.
ndf
- Input, the degrees of freedom of the numerator variance,, must be positive ( ).
fdf
- Input, the degrees of freedom of the denominator variance,, must be positive ().
tail
- Input, Optional. The tail probability type using for the F distribution
- 1 = the for upper tail probability
- 2 = the lower tail probability (Default if not set)
prob
- Output, the returned probability
Example
fcdf(1000,20,20,1)=; //ANS: 9.0714457299284E-26
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