Contents

# mkl_?bsrgemv

Computes matrix - vector product of a sparse general matrix stored in the BSR format (3-array variation) with one-based indexing (deprecated).

## Syntax

Include Files
• mkl.h
Description
This routine is deprecated. Use mkl_sparse_?_mvfrom the
Intel® oneAPI Math Kernel Library
Inspector-executor Sparse BLAS interface instead.
The
mkl_?bsrgemv
routine performs a matrix-vector operation defined as
`y := A*x`
or
`y := AT*x,`
where:
x
and
y
are vectors,
A
is an
m
-by-
m
block sparse square matrix in the BSR format (3-array variation),
A
T
is the transpose of
A
.
This routine supports only one-based indexing of the input arrays.
Input Parameters
transa
Specifies the operation.
If
transa
=
'N'
or
'n'
, then the matrix-vector product is computed as
y
:=
A
*
x
If
transa
=
'T'
or
't'
or
'C'
or
'c'
, then the matrix-vector product is computed as
y
:=
A
T
*
x
,
m
Number of block rows of the matrix
A
.
lb
Size of the block in the matrix
A
.
a
Array containing elements of non-zero blocks of the matrix
A
. Its length is equal to the number of non-zero blocks in the matrix
A
multiplied by
lb
*
lb
. Refer to
values
array description in BSR Format for more details.
ia
Array of length
(
m
+ 1)
, containing indices of block in the array
a
, such that
ia
[
i
] -
ia
[0]
is the index in the array
a
of the first non-zero element from the row
i
. The value of the last element
ia
[
m
] -
ia
[0]
is equal to the number of non-zero blocks. Refer to
rowIndex
array description in BSR Format for more details.
ja
Array containing the column indices
plus one
for each non-zero block in the matrix
A
.
Its length is equal to the number of non-zero blocks of the matrix
A
. Refer to
columns
array description in BSR Format for more details.
x
Array, size
(
m
*
lb
)
.
On entry, the array
x
must contain the vector
x
.
Output Parameters
y
Array, size at least
(
m
*
lb
)
.
On exit, the array
y
must contain the vector
y
.

#### Product and Performance Information

1

Performance varies by use, configuration and other factors. Learn more at www.Intel.com/PerformanceIndex.