next up previous contents
Next: psb_spnrmi Infinity Up: Computational routines Previous: psb_genrm2 2-Norm   Contents

psb_genrm2s -- Generalized 2-Norm of Vector

This subroutine computes a series of 2-norms on the columns of a dense matrix $x$:

\begin{displaymath}res(i) \leftarrow \Vert x(:,i)\Vert _2 \end{displaymath}

call psb_genrm2s(res, x, desc_a, info)


Table 9: Data types
$res$ $x$ Subroutine
Short Precision Real Short Precision Real psb_genrm2s
Long Precision Real Long Precision Real psb_genrm2s
Short Precision Real Short Precision Complex psb_genrm2s
Long Precision Real Long Precision Complex psb_genrm2s


Type:
Synchronous.
On Entry
x
the local portion of global dense matrix $x$.
Scope: local
Type: required
Intent: in.
Specified as: a rank one or two array or an object of type vdatapsb_T_vect_type containing numbers of type specified in Table 9.
desc_a
contains data structures for communications.
Scope: local
Type: required
Intent: in.
Specified as: an object of type descdatapsb_desc_type.

On Return
res
contains the 1-norm of (the columns of) $x$.
Scope: global
Intent: out.
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_spnrmi Infinity Up: Computational routines Previous: psb_genrm2 2-Norm   Contents