Hi Laurent, Robert, and others,

On 02/20/2013 01:33 PM, Laurent Gautier wrote:
On 2013-02-20 22:02, Hervé Pagès wrote:
Hi Robert,

Nice to hear from you!

I'm just a little bit worried that if we put normalize() in
BiocGenerics without at the same time have a "take it or leave it"
policy, then most of the authors of the 10 packages are likely going
to ignore that there is now a new normalize() in BiocGenerics.

There are roughly two schools for getting compliance:
a- enforcement
b- communication and education

Start with b-, and most will comply I think (since it will not change
their API).
For new packages there are already few requirements to be accepted to
bioconductor (all of which are not necessary fulfilled by all packages);
this would only make one more requirement.

Requirement == enforcement. Otherwise we reject the package.

My understanding of Robert's email is that people might have good
reasons for re-defining a generic that is already defined in BiocGenerics.

So here is my attempt at wrapping this up:

  (a) There seems to be a consensus (Wolfgang?) in favor of adding
      the normalize() generic to BiocGenerics.

  (b) We should strongly encourage (not enforce) existing packages and
      new packages to not redefine their own normalize() function or
      any generic function already defined in BiocGenerics.

If we agree on this, I'll add it to our post-BioC-2.12-release TODO
list. Unless I hear a big "NO" from Wolfgang who I believe is the
author/maintainer of one of the packages that define a normalize()
function.

FWIW, as a package reviewer myself, when I load the package I'm
reviewing for the first time and see warnings that it's masking
stuff defined in other packages, it's an orange light to me.
Or a red light if the masked stuff is defined in packages that are
at the bottom of the stack. So they'll need to have really really
good reasons for doing this ;-)

H.


They
didn't have any problem so far clashing with 9 other Bioc packages so
why would they care if now it's 10 instead of 9?

I'd suspect that they mostly do/did not care because either they were
not using those packages, and if they did probably not within the same R
session (so clashes were not so obvious).


Furthermore, the good citizens that modify their package to use the
normalize() in BiocGenerics will be in a situation worth than before
because, from an end user point of view, their normalize() function
(which is now a method attached to BiocGenerics::normalize) won't
seem to work anymore, even if their package was loaded last, just
because one bad citizen was loaded before (unless the end user calls
BiocGenerics::normalize()). That would be unfair.
So if I was the maintainer of one of those packages, I wouldn't see
any benefit of making that move, all the contrary, unless everybody
else also makes it.

Eh... "the Bioconductor package maintainer" as a variant of the
"Prisoner's dilemma".
;-)


I kind of agree that namespaces can accommodate the current situation,
even though, for the end user working interactively, the experience is
not really pleasant, especially when they try to access the man page for
normalize(). But if we are happy with that, then I don't really see
the need to put normalize() in BiocGenerics.

An other possible benefit of having a set on function in a
"BiocGenerics" is to suggest that some method names are more commonly
found (and make it easier for the end user by having less names to
remember).
For example, if there is a generic "plot" the right should have more
chances to be called "plot" rather than "draw", "sketch", or "paint".


Cheers,
H.


On 02/20/2013 11:52 AM, Robert Gentleman wrote:
my 2c worth

On Wed, Feb 20, 2013 at 10:45 AM, Hervé Pagès <hpa...@fhcrc.org> wrote:
Hi,

I agree with Laurent that we can't really play the semantic and concept
police. It's the responsibility of package authors to decide whether
it's appropriate or not to call "normalization" that particular
transformation they're implementing.

However I hope that we all agree on the following rule regarding the
generics that make it into BiocGenerics:

   If foo() is a generic function defined in BiocGenerics, no
   BioC package should redefine the function (either as a generic
   or an ordinary function). It can only define methods for it,
   or move away and use a different name for this functionality.

  but really the point of namespaces is that you don't need to do that.
  And we really don't want to be the naming police.
   The sole advantage of BiocGenerics, I think, is that there is a
common
and standard location for a set of generic functions that get used in
different
packages.  This allows package authors to add methods that specialize
the
behavior of a generic function.  They have some confidence that the
generic will always exist and hence can plan accordingly.  It
hopefully reduces dependencies between packages.

   I don't think it should define a set of reserved words, that seems
counter
productive.
    There are often good reasons why the same name is used for different
concepts (normalize being one of them).  And in some cases a single
generic suffices, but in others it will not.  Places where a single
generic
fall apart are when there are really different argument lists, and
where inheritance (and hence things like NextMethod) are going to get
messed
up if the disparate methods are all linked to a single generic. Generics
are really concepts - and the methods are realizations of those
concepts.

   Of course, packages that define functions whose names clash with
BiocGenerics will cause problems, and they would generally be best
to avoid that, but really I don't think I would advocate any sort of
prohibition.



Does that sound reasonable? Otherwise that would kind of defeat the
purpose of having the BiocGenerics package in the 1st place.

To me, having 10 BioC packages defining a normalize() function is far
from being ideal. I think having it defined in BiocGenerics would
improve things a little bit. Also one potential positive side effect
I see is that it would give an opportunity to the authors of those
10 packages to reconsider if they still want to ride the normalize()
poney or not. Maybe some of them won't and they'll pick up another
name. Not something we can really decide for them...

H.



On 02/20/2013 09:47 AM, Laurent Gautier wrote:

On 2013-02-20 17:32, Schalkwyk, Leonard wrote:


Is this not just an indication that normalize is now a poor choice of
a function name?


If the package authors called the functions "normalize", this means
either:
1- at least some of the package authors have named a function
performing
an action that is inappropriately described as "normalize"
2- all functions "normalize" do perform an action that can be
described
with that verb

Without more details, I'd vote for 2.

(more below)


LEo

On 20 Feb 2013, at 16:14, Wolfgang Huber wrote:

Hi

is it clear that all these different functions (methods) share
similar semantics and enough (conceptually) of their interface?


Playing the semantic and concept police would come after defining
things
like ontologies of data processing; I am not sure this should be a
priority.
I'd see working out a minimal common signature that keeps everyone
going
with a minimal fuss come first.


Wouldn't the implication be that preemptively every possible string
of characters should already be defined as a generic function in
BiocGenerics?


No. Otherwise this would probably also mean that R's S4 system
should in
fact define all possible strings as generics, which by extension would
also mean that generic functions do not need to be explicitly
declared:
since all possible generics would be declared, it is more practical to
implicitly assume any given function has already generic declared. S4
has notions about implicit generic functions; a starting point is the
man page for setGeneric().




     Best wishes
     Wolfgang

Il giorno Feb 20, 2013, alle ore 11:04 AM, Laurent Gatto
<lg...@cam.ac.uk> ha scritto:

On 19 February 2013 22:44, Hervé Pagès <hpa...@fhcrc.org> wrote:

Hi Laurent, and maintainers of packages with a normalize()
function,


On 02/15/2013 04:28 AM, Laurent Gatto wrote:

A quick (and incomplete) manual search using
http://search.bioconductor.jp/ suggest the following usage of
normalize:

As a function:
xps::normalize
codelink::normalize
EBImage::normalize
diffGeneAnalysis::normalize

Defining a generic and methods:
oligo::normalize
flowCore::normalize
MSnbase::normalize
isobar::normalize

and

several normalize\.[*+] functions

Would it be reasonable to add a normalize generic definition to
BiocGenerics?  The generic definitions in the above packages
differ,
however.


Sounds good to me.

However, since the various normalize() functions have different
signatures, we need to agree on what the signature of the generic
in BiocGenerics should be.

Here is a summary of the situation:

** xps package: normalize() is an ordinary function with the
     following arg list:

       normalize(xps.data, filename=character(0), filedir=getwd(),
                 tmpdir="", update=FALSE, select="all",
method="mean",
                 option="transcript:all", logbase="0",
exonlevel="",
                 refindex=0, refmethod="mean",
params=list(0.02, 0),
                 add.data=TRUE, verbose=TRUE)

     The package also defines normalize.constant(),
normalize.lowess(),
     normalize.quantiles(), normalize.supsmu(), which are also
ordinary
     functions (not S3 methods), and have similar but slightly
     different arg lists.

** codelink package: Ordinary function with the following args:

       normalize(object, method="quantiles", log.it=TRUE,
                 preserve=FALSE, weights=NULL, verbose=FALSE)

** EBImage package: Ordinary function with the following args:

       normalize(x, separate=TRUE, ft=c(0, 1))

** diffGeneAnalysis package: Ordinary function with the following
     args:

       normalize(rawdata, numSlides, ctrl, expm, ctrlbg=0.30,
                 expmbg=0.30)

** deepSNV package: S4 generic with the following args:

       normalize(test, control, ...)

** isobar package: S4 generic with the following args:

       normalize(x, f=median, target="intensity",
exclude.protein=NULL,
                    use.protein=NULL, f.doapply=TRUE, log=TRUE,
                    channels=NULL, na.rm=FALSE, per.file=TRUE,
...)

** affy package: S4 generic with the following args:

       normalize(object, ...)

** flowCore package: S4 generic with the following args:

       normalize(data, x, ...)

** MSnbase package: S4 generic with the following args:

       normalize(object, method, ...)

** oligo package: S4 generic with the following args:

       normalize(object, method=normalizationMethods(),
                 copy=TRUE, subset=NULL,
                 target='core', verbose=TRUE, ...)

So it looks like the greatest common factor is normalize(x, ...).
Not too surprising for a generic that covers such a wide range of
related but slightly different concepts / algorithms.

One technical difficulty though is that, even though almost all
these
functions seem to take an S4 object as their 1st arg, some of them
don't:

(a) For EBImage::normalize(), 'x' can be an ordinary array in
      addition to an Image object.

(b) For diffGeneAnalysis::normalize(), 'rawdata' is an ordinary
      matrix.

(c) For deepSNV::normalize(), 'test' can be an ordinary matrix
      in addition to a deepSNV object.

(d) For oligo::normalize(), 'object' can be an ordinary matrix
      in addition to a FeatureSet object.

So how can we disambiguate when the first arg is an ordinary
matrix?
IMO normalize() should fail in that case i.e. no package should
define
methods for ordinary arrays or matrices. Not ideal but better
than the
current situation where what is returned depends on which
package was
loaded last.

I could put normalize(x, ...) in BiocGenerics if nobody
objects, but
that's all. I don't have time to fix the 10 packages that this
change
will affect. However, I'd rather wait the beginning of the Bioc
2.13
devel cycle (April) for such a change. For some packages like
diffGeneAnalysis (which doesn't use S4 at all), that will probably
require a significant amount of changes since it will need to pass
the data to normalize in an S4 container instead of an ordinary
matrix.

Comments and suggestions are welcome.

Fine by me.

Laurent

Thanks,
H.

Best wishes,

Laurent

_______________________________________________
Bioc-devel@r-project.org mailing list
https://stat.ethz.ch/mailman/listinfo/bioc-devel

--
Hervé Pagès

Program in Computational Biology
Division of Public Health Sciences
Fred Hutchinson Cancer Research Center
1100 Fairview Ave. N, M1-B514
P.O. Box 19024
Seattle, WA 98109-1024

E-mail: hpa...@fhcrc.org
Phone:  (206) 667-5791
Fax:    (206) 667-1319

_______________________________________________
Bioc-devel@r-project.org mailing list
https://stat.ethz.ch/mailman/listinfo/bioc-devel

_______________________________________________
Bioc-devel@r-project.org mailing list
https://stat.ethz.ch/mailman/listinfo/bioc-devel

_______________________________________________
Bioc-devel@r-project.org mailing list
https://stat.ethz.ch/mailman/listinfo/bioc-devel


_______________________________________________
Bioc-devel@r-project.org mailing list
https://stat.ethz.ch/mailman/listinfo/bioc-devel


--
Hervé Pagès

Program in Computational Biology
Division of Public Health Sciences
Fred Hutchinson Cancer Research Center
1100 Fairview Ave. N, M1-B514
P.O. Box 19024
Seattle, WA 98109-1024

E-mail: hpa...@fhcrc.org
Phone:  (206) 667-5791
Fax:    (206) 667-1319

_______________________________________________
Bioc-devel@r-project.org mailing list
https://stat.ethz.ch/mailman/listinfo/bioc-devel






--
Hervé Pagès

Program in Computational Biology
Division of Public Health Sciences
Fred Hutchinson Cancer Research Center
1100 Fairview Ave. N, M1-B514
P.O. Box 19024
Seattle, WA 98109-1024

E-mail: hpa...@fhcrc.org
Phone:  (206) 667-5791
Fax:    (206) 667-1319

_______________________________________________
Bioc-devel@r-project.org mailing list
https://stat.ethz.ch/mailman/listinfo/bioc-devel

Reply via email to