Visible to Intel only — GUID: GUID-5E3F596A-F6B0-4E3D-8FE3-DAFEBFABAAA7
Visible to Intel only — GUID: GUID-5E3F596A-F6B0-4E3D-8FE3-DAFEBFABAAA7
?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
val = slange( norm, m, n, a, lda, work )
val = dlange( norm, m, n, a, lda, work )
val = clange( norm, m, n, a, lda, work )
val = zlange( norm, m, n, a, lda, work )
Include Files
- mkl.fi
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
The data types are given for the Fortran interface.
- norm
-
CHARACTER*1. Specifies the value to be returned by the routine:
= 'M' or 'm': val = max(abs(Aij)), 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
-
INTEGER. The number of rows of the matrix A.
m≥ 0. When m = 0, ?lange is set to zero.
- n
-
INTEGER. The number of columns of the matrix A.
n≥ 0. When n = 0, ?lange is set to zero.
- a
-
REAL for slange
DOUBLE PRECISION for dlange
COMPLEX for clange
DOUBLE COMPLEX for zlange
Array, DIMENSION (lda,n).
Array a contains the m-by-n matrix A.
- lda
-
INTEGER. The leading dimension of the array a.
.
- work
-
REAL for slange and clange.
DOUBLE PRECISION for dlange and zlange.
Workspace array, DIMENSION max(1,lwork), where lwork≥m when norm = 'I'; otherwise, work is not referenced.
Output Parameters
- val
-
REAL for slange/clange
DOUBLE PRECISION for dlange/zlange
Value returned by the function.