Developer Reference for Intel® oneAPI Math Kernel Library for Fortran
?lanst/?lanht
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 symmetric or complex Hermitian tridiagonal matrix.
Syntax
valslanst ( norm , n , d , e )
valdlanst ( norm , n , d , e )
valclanht ( norm , n , d , e )
valzlanht ( norm , n , d , e )
Include Files
mkl.fi
Description
slanst dlanst clanht zlanht
The functions ?lanst / ?lanht return the value of the 1-norm, or the Frobenius norm, or the infinity norm, or the element of largest absolute value of a real symmetric or a complex Hermitian tridiagonal matrix A .
Input Parameters
- norm
-
CHARACTER*1 . Specifies the value to be returned by the routine: = ‘M’ or ‘m’: val = max(abs(A_{ij})) , 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).
- n
-
INTEGER . The order of the matrix A . n≥ 0 . When n = 0 , ?lanst / ?lanht is set to zero.
- d
-
REAL for slanst / clanht DOUBLE PRECISION for dlanst / zlanht Array, DIMENSION ( n ). The diagonal elements of A .
- e
-
REAL for slanst DOUBLE PRECISION for dlanst COMPLEX for clanht DOUBLE COMPLEX for zlanht Array, DIMENSION ( n -1). The ( n -1) sub-diagonal or super-diagonal elements of A .
Output Parameters
- val
-
REAL for slanst / clanht DOUBLE PRECISION for dlanst / zlanht Value returned by the function.