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psb_spnrmi -- Infinity Norm of Sparse Matrix

This function computes the infinity-norm of a matrix $A$:


\begin{displaymath}nrmi \leftarrow \Vert A\Vert _\infty \end{displaymath}

where:
$A$
represents the global matrix $A$


Table 11: Data types
$A$ Function
Short Precision Real psb_spnrmi
Long Precision Real psb_spnrmi
Short Precision Complex psb_spnrmi
Long Precision Complex psb_spnrmi


psb_spnrmi(A, desc_a, info)

Type:
Synchronous.
On Entry
a
the local portion of the global sparse matrix $A$.
Scope: local
Type: required
Intent: in.
Specified as: an object of type spdatapsb_Tspmat_type.
desc_a
contains data structures for communications.
Scope: local
Type: required
Intent: in.
Specified as: an object of type descdatapsb_desc_type.
On Return
Function value
is the infinity-norm of sparse submatrix $A$.
Scope: global
Specified as: a long precision real number.
info
Error code.
Scope: local
Type: required
Intent: out.
An integer value; 0 means no error has been detected.


next up previous contents
Next: psb_spmm Sparse Up: Computational routines Previous: psb_spnrm1 1-Norm   Contents