naginterfaces.library.rand.dist_f¶
- naginterfaces.library.rand.dist_f(n, df1, df2, statecomm)[source]¶
dist_f
generates a vector of pseudorandom numbers taken from an (or Fisher’s variance ratio) distribution with and degrees of freedom.For full information please refer to the NAG Library document for g05sh
https://support.nag.com/numeric/nl/nagdoc_30.2/flhtml/g05/g05shf.html
- Parameters
- nint
, the number of pseudorandom numbers to be generated.
- df1int
, the number of degrees of freedom of the distribution.
- df2int
, the number of degrees of freedom of the distribution.
- statecommdict, RNG communication object, modified in place
RNG communication structure.
This argument must have been initialized by a prior call to
init_repeat()
orinit_nonrepeat()
.
- Returns
- xfloat, ndarray, shape
The pseudorandom numbers from the specified -distribution.
- Raises
- NagValueError
- (errno )
On entry, .
Constraint: .
- (errno )
On entry, .
Constraint: .
- (errno )
On entry, .
Constraint: .
- (errno )
On entry, [‘state’] vector has been corrupted or not initialized.
- Notes
The distribution has PDF (probability density function)
dist_f
calculates the valueswhere and are generated by
dist_gamma()
from gamma distributions with parameters and respectively (i.e., from -distributions with and degrees of freedom).One of the initialization functions
init_repeat()
(for a repeatable sequence if computed sequentially) orinit_nonrepeat()
(for a non-repeatable sequence) must be called prior to the first call todist_f
.
- References
Knuth, D E, 1981, The Art of Computer Programming (Volume 2), (2nd Edition), Addison–Wesley