ML_DLANGE – Computes one of the matrix norms of a general matrix

Block SymbolLicensing group: STANDARD

Function Description
The output references yA and yWORK are always set to the corresponding input references uA and uWORK. If HLD = on then nothing is computed otherwise the LAPACK function DLANGE is called internally:

value = DLANGE(sNORM, M, N, uA, LDA, uWORK;

where parameters of DLACPY are set in the following way:

Integer input norm is mapped to the string sNORM: ${0, 1} \to "F"$ (Frobenius norm), ${2} \to "M"$ (max(abs(A(i,j)))), ${3} \to "1"$ (one norm) and ${4} \to "I"$ (infinity norm).
M is number of rows of the matrix referenced by uA.
N is number of columns of the matrix referenced by uA.
LDA is the leading dimension of the matrix referenced by uA.
uWORK is the working vector of dimension $LWORK \geq M$ . uWORK is used only for infinity norm, otherwise it is not referenced.

The error flag E is set to on if:

the reference uA is not defined (i.e. input uA is not connected),
the reference uWORK is not defined for $norm = 4$ (i.e. input uWORK is not connected).

See LAPACK documentation [7] for more details.
Use the block MB_DNRM2 for computation of Frobenius norm of a vector.

Inputs

uA	Input reference to matrix A	Reference
uWORK	Input reference to working vector WORK	Reference
norm	The selected matrix norm $↓$ 0 $↑$ 4	Long (I32)
HLD	Hold	Bool

Outputs

yA	Output reference to matrix A	Reference
yWORK	Output reference to working vector WORK	Reference
value	Return value of the function	Double (F64)
E	Error indicator	Bool

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