4.9 psb_genrm2s — Generalized 2-Norm of Vector

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

res(i) ← ∥x(:,i)∥2

call psb_genrm2s(res, x, desc_a, info)





res x Subroutine



Short Precision RealShort Precision Real psb_genrm2s
Long Precision Real Long Precision Real psb_genrm2s
Short Precision RealShort Precision Complexpsb_genrm2s
Long Precision Real Long Precision Complex psb_genrm2s




Table 9: Data types

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 psb_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 psb_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.