?lantr
?lantr
Returns the value of the 1-norm, or the Frobenius norm, or the infinity norm, or the element of largest absolute value of a trapezoidal or triangular matrix.
Syntax
float
LAPACKE_slantr
(
char
*
norm
,
char
*
uplo
,
char
*
diag
,
lapack_int
*
m
,
lapack_int
*
n
,
const
float
*
a
,
lapack_int
*
lda
,
float
*
work
);
double
LAPACKE_dlantr
(
char
*
norm
,
char
*
uplo
,
char
*
diag
,
lapack_int
*
m
,
lapack_int
*
n
,
const
double
*
a
,
lapack_int
*
lda
,
double
*
work
);
float
LAPACKE_clantr
(
char
*
norm
,
char
*
uplo
,
char
*
diag
,
lapack_int
*
m
,
lapack_int
*
n
,
const
lapack_complex_float
*
a
,
lapack_int
*
lda
,
float
*
work
);
double
LAPACKE_zlantr
(
char
*
norm
,
char
*
uplo
,
char
*
diag
,
lapack_int
*
m
,
lapack_int
*
n
,
const
lapack_complex_double
*
a
,
lapack_int
*
lda
,
double
*
work
);
Include Files
- mkl.h
Description
The function
?lantr
returns the value of the 1-norm, or the Frobenius norm, or the infinity norm, or the element of largest absolute value of a trapezoidal or triangular 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':, largest absolute value of the matrixval=max(abs(Aij))A.='1'or'O'or'o':, 1-norm of the matrixval=norm1(A)A(maximum column sum),='I'or'i':, infinity norm of the matrixval=normI(A)A(maximum row sum),='F','f','E'or'e':, Frobenius norm of the matrixval=normF(A)A(square root of sum of squares).
- uplo
- Specifies whether the matrixAis upper or lower trapezoidal.='U': Upper trapezoidal='L': Lower trapezoidal.Note thatAis triangular instead of trapezoidal if.m=n
- diag
- Specifies whether or not the matrixAhas unit diagonal.='N': Non-unit diagonal='U': Unit diagonal.
- m
- The number of rows of the matrixA., and ifm≥0,uplo='U'.m≤nWhen,m= 0?lantris set to zero.
- n
- The number of columns of the matrixA., and ifn≥0,uplo='L'.n≤mWhen,n= 0?lantris set to zero.
- a
- Array, size at leastmax(1,for column major andlda*n)max(1,for row major layout.lda*m)The trapezoidal matrixA(Ais triangular if.m=n)If, the leadinguplo='U'm-by-nupper trapezoidal part of the arrayacontains the upper trapezoidal matrix, and the strictly lower triangular part ofAis not referenced.If, the leadinguplo='L'm-by-nlower trapezoidal part of the arrayacontains the lower trapezoidal matrix, and the strictly upper triangular part ofAis not referenced. Note that when, the diagonal elements ofdiag='U'Aare not referenced and are assumed to be one.
- lda
- The leading dimension of the arraya.lda≥max(m,1)for column major layout and.≥max(1,n) for row major layout