Developer Reference for Intel® oneAPI Math Kernel Library - C

Developer Reference

  • 2021.1
  • 12/04/2020
  • Public Content
Contents

?lange

Returns the value of the 1-norm, Frobenius norm, infinity-norm, or the largest absolute value of any element of a general rectangular matrix.

Syntax

float
LAPACKE_slange
(
int
matrix_layout
,
char
norm
,
lapack_int
m
,
lapack_int
n
,
const
float
*
a
,
lapack_int
lda
);
double
LAPACKE_dlange
(
int
matrix_layout
,
char
norm
,
lapack_int
m
,
lapack_int
n
,
const
double
*
a
,
lapack_int
lda
);
float
LAPACKE_clange
(
int
matrix_layout
,
char
norm
,
lapack_int
m
,
lapack_int
n
,
const
lapack_complex_float
*
a
,
lapack_int
lda
);
double
LAPACKE_zlange
(
int
matrix_layout
,
char
norm
,
lapack_int
m
,
lapack_int
n
,
const
lapack_complex_double
*
a
,
lapack_int
lda
);
Include Files
  • mkl.h
Description
The function
?lange
 returns the value of the 1-norm, or the Frobenius norm, or the infinity norm, or the element of largest absolute value of a real/complex matrix
A
.
Input Parameters
A
<datatype>
 placeholder, if present, is used for the C interface data types in the C interface section above. See C Interface Conventions for the C interface principal conventions and type definitions.
norm
Specifies the value to be returned by the routine:
=
'M'
 or
'm':
val
 =
max
(
abs
(
A
i
j
))
, largest absolute value of the matrix
A
.
=
'1'
 or
'O'
 or
'o':
val
 =
norm1
(
A
)
, 1-norm of the matrix
A
 (maximum column sum),
=
'I'
 or
'i':
val
 =
normI
(
A
)
, infinity norm of the matrix
A
 (maximum row sum),
=
'F'
,
'f'
,
'E'
 or
'e':
val
 =
normF
(
A
)
, Frobenius norm of the matrix
A
 (square root of sum of squares).
m
The number of rows of the matrix
A
.
m
≥
 0
. When
m
 = 0
,
?lange
 is set to zero.
n
The number of columns of the matrix
A
.
n
≥
 0
. When
n
 = 0
,
?lange
 is set to zero.
a
Array, size at least
max(1,
lda
*
n
)
 for column major and
max(1,
lda
*
m
)
 for row major layout.
Array
a
 contains the
m
-by-
n
 matrix
A
.
lda
The leading dimension of the array
a
.
lda
≥
 max(
n
,1)
 for column major layout and max(1,
n
) for row major layout
.

Product and Performance Information

1

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