26
Numerics library
[numerics]
26.6
Random number generation
[rand]
26.6.9
Random number distribution class templates
[rand.dist]
26.6.9.5
Normal distributions
[rand.dist.norm]
26.6.9.5.5
Class template
fisher_f_distribution
[rand.dist.norm.f]
1
#
A
fisher_f_distribution
random number distribution produces random numbers
x
≥
0
distributed according to the probability density function
p
(
x
|
m
,
n
)
=
Γ
(
(
m
+
n
)
/
2
)
Γ
(
m
/
2
)
Γ
(
n
/
2
)
⋅
(
m
n
)
m
/
2
⋅
x
(
m
/
2
)
−
1
⋅
(
1
+
m
x
n
)
−
(
m
+
n
)
/
2
.
🔗
template
<
class
RealType
=
double
>
class
fisher_f_distribution
{
public
:
// types
using
result_type
=
RealType;
using
param_type
=
unspecified
;
// constructor and reset functions
fisher_f_distribution
(
)
:
fisher_f_distribution
(
1.0
)
{
}
explicit
fisher_f_distribution
(
RealType m, RealType n
=
1.0
)
;
explicit
fisher_f_distribution
(
const
param_type
&
parm
)
;
void
reset
(
)
;
// generating functions
template
<
class
URBG
>
result_type
operator
(
)
(
URBG
&
g
)
;
template
<
class
URBG
>
result_type
operator
(
)
(
URBG
&
g,
const
param_type
&
parm
)
;
// property functions
RealType m
(
)
const
; RealType n
(
)
const
; param_type param
(
)
const
;
void
param
(
const
param_type
&
parm
)
; result_type min
(
)
const
; result_type max
(
)
const
;
}
;
🔗
explicit
fisher_f_distribution
(
RealType m, RealType n
=
1
)
;
2
#
Preconditions
:
0
<
m
and
0
<
n
.
3
#
Remarks
:
m
and
n
correspond to the respective parameters of the distribution
.
🔗
RealType m
(
)
const
;
4
#
Returns
: The value of the
m
parameter with which the object was constructed
.
🔗
RealType n
(
)
const
;
5
#
Returns
: The value of the
n
parameter with which the object was constructed
.