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psb_gedots -- Generalized Dot Product

This subroutine computes a series of dot products among the columns of two dense matrices $x$ and $y$:

\begin{displaymath}res(i) \leftarrow x(:,i)^T y(:,i)\end{displaymath}

If the matrices are complex, then the usual convention applies, i.e. the conjugate transpose of $x$ is used. If $x$ and $y$ are of rank one, then $res$ is a scalar, else it is a rank one array.

call psb_gedots(res, x, y, desc_a, info)

Table 3: Data types
$res$, $x$, $y$ Subroutine
Short Precision Real psb_gedots
Long Precision Real psb_gedots
Short Precision Complex psb_gedots
Long Precision Complex psb_gedots


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 3. The rank of $x$ must be the same of $y$.
y
the local portion of global dense matrix $y$.
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 3. The rank of $y$ must be the same of $x$.
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
is the dot product of subvectors $x$ and $y$.
Scope: global
Intent: out.
Specified as: a number or a rank-one array of the data type indicated in Table 2.
info
Error code.
Scope: local
Type: required
Intent: out.
An integer value; 0 means no error has been detected.


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Next: psb_geamax Infinity-Norm Up: Computational routines Previous: psb_gedot Dot   Contents