[
https://issues.apache.org/jira/browse/MATH-613?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13071939#comment-13071939
]
Sébastien Brisard commented on MATH-613:
----------------------------------------
I'm sorry, I really can't find the way to do it. In a previous issue (which is
even messier), someone suggested that I should give all patches the same name,
but this obviously does not work.
I'll probably need some time until my proposals are OK at the first attempt.
Meanwhile, is there another way to propose patches, and attach the "final"
patch only to the JIRA issue?
Sebastien
> Equivalent of Blas DAXPY
> ------------------------
>
> Key: MATH-613
> URL: https://issues.apache.org/jira/browse/MATH-613
> Project: Commons Math
> Issue Type: New Feature
> Affects Versions: 3.0
> Reporter: Sébastien Brisard
> Priority: Minor
> Labels: linear, vector
> Attachments: MATH-613-20110727.patch, MATH-613-20110727.patch,
> MATH-613-20110727.patch
>
>
> In Blas, the method {{DAXPY}} computes an in-place linear combination of two
> vectors. More precisely, a call to {{DAXPY(a, x, y)}} updates vector {{y}}
> with the value of {{a * x + y}}. This can lead to very compact code, which I
> feel the need for in Commons-Math. However, DAXPY also has its limitations.
> For example, it cannot perform the other combination {{y <- x + a * y}}.
> I think it would be useful that {{RealVector}} had a method for computing {{a
> * this + b * y}}, and storing the result in {{this}}. In the spirit of the
> {{mapToSelf}} method, I propose to create two new methods in {{Interface
> RealVector}}
> {noformat}RealVector map(BivariateRealFunction f, RealVector y){noformat}
> and
> {noformat}RealVector mapToSelf(BivariateRealFunction f, RealVector
> y){noformat}
> The former would return a new vector {{v}} such that
> {noformat}v[i] <- f(this[i], y[i])}}{noformat}
> and the latter would update {{this}},
> {noformat}this[i] <- f(this[i], y[i]){noformat}
> Emulating {{DAXPY}} would then simply be a matter of implementing the
> appropriate bivariate function.
> While we are at it, how about
> {noformat}RealVector map(TrivariateRealFunction f, RealVector y, RealVector
> z){noformat}
> {noformat}RealVector mapToSelf(TrivariateRealFunction f, RealVector y,
> RealVector z){noformat}
--
This message is automatically generated by JIRA.
For more information on JIRA, see: http://www.atlassian.com/software/jira
