f06yrf performs one of the symmetric rank-
update operations
where
and
are real matrices,
is an
real symmetric matrix, and
and
are real scalars.
None.
None.
-
1:
– Character(1)
Input
-
On entry: specifies whether the upper or lower triangular part of
is stored.
- The upper triangular part of is stored.
- The lower triangular part of is stored.
Constraint:
or .
-
2:
– Character(1)
Input
-
On entry: specifies the operation to be performed.
- .
- or
- .
Constraint:
, or .
-
3:
– Integer
Input
-
On entry: , the order of the matrix ; the number of rows of and if , or the number of columns of and if or .
Constraint:
.
-
4:
– Integer
Input
-
On entry: , the number of columns of and if , or the number of rows of and if or .
Constraint:
.
-
5:
– Real (Kind=nag_wp)
Input
-
On entry: the scalar .
-
6:
– Real (Kind=nag_wp) array
Input
-
Note: the second dimension of the array
a
must be at least
if
and at least
if
or
.
On entry: the matrix ; is if , or if or .
-
7:
– Integer
Input
-
On entry: the first dimension of the array
a as declared in the (sub)program from which
f06yrf is called.
Constraints:
- if , ;
- if or , .
-
8:
– Real (Kind=nag_wp) array
Input
-
Note: the second dimension of the array
b
must be at least
if
and at least
if
or
.
On entry: the matrix ; is if , or if or .
-
9:
– Integer
Input
-
On entry: the first dimension of the array
b as declared in the (sub)program from which
f06yrf is called.
Constraints:
- if , ;
- if or , .
-
10:
– Real (Kind=nag_wp)
Input
-
On entry: the scalar .
-
11:
– Real (Kind=nag_wp) array
Input/Output
-
Note: the second dimension of the array
c
must be at least
.
On entry: the
symmetric matrix
.
- If , the upper triangular part of must be stored and the elements of the array below the diagonal are not referenced.
- If , the lower triangular part of must be stored and the elements of the array above the diagonal are not referenced.
On exit: the updated matrix .
-
12:
– Integer
Input
-
On entry: the first dimension of the array
c as declared in the (sub)program from which
f06yrf is called.
Constraint:
.
None.
Not applicable.
Background information to multithreading can be found in the
Multithreading documentation.
Please consult the
X06 Chapter Introduction for information on how to control and interrogate the OpenMP environment used within this routine. Please also consult the
Users' Note for your implementation for any additional implementation-specific information.
None.
None.