Re: [Rd] [R] Semantics of sequences in R

2009-02-24 Thread Berwin A Turlach
On Mon, 23 Feb 2009 20:27:23 +0100
Wacek Kusnierczyk waclaw.marcin.kusnierc...@idi.ntnu.no wrote:

 Berwin A Turlach wrote:

  [...]
  judging from your question, you couldn't possibly see sorting
  routines in other languages.
  
 
  Quite likely, or the other languages that I regularly use (C,
  Fortran) have even more primitive sorting facilities. 

 
 i apologize, [...]

Apology accepted.

[...]
  No, if that is what you want.  And I guess it is one way of
  sorting a list.  The question is what should be the default
  way? 
  one possible answer is: none.  (i have already given this answer
  previously, if you read carefully it's still there).  sort.list
  *should* demand an additional comparator argument.  at least, it
  should demand it if the argument to be sorted is a list, rather
  than a non-list vector (if you still need to use sort.list on
  non-lists). 
 
  So when are you sending your patch to implement this facility?
 
 as i said, you seem to have a severe bug in thinking about
 collaborative development.
 
 i am sending *no* patch for this.  the issue has to be first discussed
 on the design level, and only then, if accepted, should anyone -- me,
 for example -- make an attempt to implement it.  tell me you want to
 listen to what i have to say, and we can discuss.  

I could tell you that I will listen and we can discuss this until the
cows come home.  This will not change one iota since neither of us have
the power to implement changes in R.  You keep barking up the wrong
tree.  

So far I have seen only one posting of an R-core member in this thread
(but perhaps he has started further discussion on the R-core mailing
list to which we are not privy), but if you want to have discussion and
acceptance before you do anything, you have to get R core involved.

Since for the kind of work for which I am using R a facility for
sorting lists is not crucial, I am rather indifferent about whether
such a facility should exist and, if so, how it should be designed.

 telling me i have a chip on my shoulder is rather unhelpful.

Well, then stop acting as if you are running around with chips on your
shoulders.  Behaving in such a manner is rather counter productive in
the R community (at least from my experience/observation).  The same
with publicly stating that you do certain things with the purpose of
annoying certain persons.  I am just pointing out that your behaviour
is counter productive but it is really up to you on whether you change
or want to continue in your ways.

There is a nice German proverb that sums all this up wie man in den
Wald reinruft so schallt es heraus.  Unfortunately, an equivalent
English proverb does not exist, but perhaps the Norwegians have
something similar

 snip

  R is open source.  Check out the svn version, fix what you
  consider needs fixing, submit a patch, convince R core that the
  patch fixes a real problem/is an improvement/does not break too
  much.  Then you have a better chance in achieving something.  

  no, berwin.  this is a serious bug in thinking.  people should be
  allowed -- *encouraged* -- to discuss the design *before* they even
  attempt to write patches. 
  
 
  And what makes you believe this is not the case?   I have seen over
  the years e-mails to R-devel along the lines I am thinking of a
  change along [lots of details and reasoning for the change]; would
  patches that implement this be accepted? and these e-mails were
  discussed more often than not.  However, in the end, the only
  people who can commit changes to the R code are the members of
  R-core, thus they will have the final word of design issues (and,
  as I assume, they discuss, among other things, design issues on the
  private mailing list of R-core member).  But you can discuss this
  issues before writing a patch. 
 
 how many such mails have you seen?  

A few over the years, but the more R progresses/matures the less of
such e-mail happens.

 i've been on r-devel for six months, and haven't seen many.  

Well, six month is a rather narrow sampling window

 on the other hand, i have seen quite a few responses that were
 bashing a user for reporting a non-existent bug or submitting an
 annoying patch.

In didactic terms those are negative motivations/reinforcements;
opinion differ on how effective they are to reach certain learning
outcomes.   

  And I am sure that if you had sent an e-mail to r-devel pointing out
  that the binary operator , when called in the non-standard way 
  ''(1,2,3), does not check the number of arguments while other
  binary operators (e.g. '+'(1,2,3) or '*'(1,2,3)) do such checks,
  and provided a patch that implemented such a check for '' (and
  presumably other comparison operators), then that patch would have
  been acknowledged and applied.

 
 it has been fixed immediately by martin. 

Yes, and, again, you could not help yourself telling the developers
what you think they should do, could you?  As I 

Re: [Rd] [R] are arithmetic comparison operators binary?

2009-02-24 Thread Martin Maechler
 WK == Wacek Kusnierczyk waclaw.marcin.kusnierc...@idi.ntnu.no
 on Mon, 23 Feb 2009 19:29:31 +0100 writes:

WK Martin Maechler wrote:
 WK == Wacek Kusnierczyk waclaw.marcin.kusnierc...@idi.ntnu.no
 on Mon, 23 Feb 2009 12:06:32 +0100 writes:
 
 
 Thank you, Wacek, 
 though .. wrong mailing list 
 

WK apologies.  i was actually asking for explanation, assuming that it
WK might be my misunderstanding, rather than reporting a bug.

( yes; but it is really a technical topic, also touching on
  extending R [below], hence -- R-devel )

WK the man page for relational operators (see, e.g., ?'') says:
WK 
WK Binary operators which allow the comparison of values in atomic vectors.
 
WK Arguments:
 
WK x, y: atomic vectors, symbols, calls, or other objects for which
WK methods have been written.
WK 
 
WK it is somewhat surprizing that the following works:
 
WK ''(1)
WK # logical(0)
 
WK ''()
WK # logical(0)
 
WK ''(1,2,3)
WK # TRUE
 
 a bit surprising (sic!), indeed, even for me.
 Thanks for your notice and report!
 

WK you're welcome. 

WK shouldn't the tests have captured it?  i think you should have a check
WK for every feature following from the docs.  

yes, we should.  

   R is free software and comes with ABSOLUTELY NO WARRANTY.
   You are welcome to ..
 .

   R is a collaborative project with many contributors.

I think we'd gladly accept well-written  commented extra
  R-x.y.z/tests/foo.R  
files or patches to existing ./tests/*.R 
particularly if the contributor shows the new tests are
systematically covering currently untested areas...
Again: this really belongs to R-devel

-- I'm CCing there  {and write a quick reply on R-help about
the mailing list redirection}

WK plus those undocumented, but assumed by the developers.

  ;-) :-)

Indeed, we are also grateful for (concise!) patches to  man/*.Rd
help files.

 If you'd looked a bit in the sources, you'd seen that they
 really are supposed to be binary only.
 

WK it wouldn't be nonsensical to let them be of arbitrary arity (in a
WK well-documented manner), though it might confuse users.

Yes (to the latter).  One of the beauties of S and R is the
syntax closeness to  mathematical notation.
Many of us know that  Lisp  has beauties that S can never have,
but that's really in different beauty-space. 


 A very small change in the sources does accomplish this, passes
 the standard checks (and I cannot imagine reasonable code that
 would have relied on the more lenient behavior), so
 this will have changed in one of the next versions of R-devel.
 

WK thanks.

WK just a question (i haven't checked the sources, maybe i should):  what
WK is it that happens when one of the operators is called with n = 0 or 1
WK argument?  how does it come up with logical(0) rather than NA?

In some of the cases  e.g. 
   ''(1)   

it basically does   [empty]  1  and hence returns the same as

   NULL  1

Regards,
Martin Maechler, ETH Zurich

__
R-devel@r-project.org mailing list
https://stat.ethz.ch/mailman/listinfo/r-devel


Re: [Rd] [R] Semantics of sequences in R

2009-02-24 Thread Wacek Kusnierczyk
Berwin A Turlach wrote:

 i am sending *no* patch for this.  the issue has to be first discussed
 on the design level, and only then, if accepted, should anyone -- me,
 for example -- make an attempt to implement it.  tell me you want to
 listen to what i have to say, and we can discuss.  
 

 I could tell you that I will listen and we can discuss this until the
 cows come home.  This will not change one iota since neither of us have
 the power to implement changes in R.  You keep barking up the wrong
 tree.  
   

i am barking on the list;  whoever is the appropriate person to react,
has the chance to read and react.  i don't think it's appropriate to
send my messages to x or y personally.  what is the right tree, you say?

 So far I have seen only one posting of an R-core member in this thread
 (but perhaps he has started further discussion on the R-core mailing
 list to which we are not privy), but if you want to have discussion and
 acceptance before you do anything, you have to get R core involved.

 Since for the kind of work for which I am using R a facility for
 sorting lists is not crucial, I am rather indifferent about whether
 such a facility should exist and, if so, how it should be designed.

   

i discussed these things with you, because you responded.  this made me
think you were not indifferent, but anyway i kept ccing to the list
precisely because because i don't think you're the right person to make
a decision or suggest the next steps.

 telling me i have a chip on my shoulder is rather unhelpful.
 

 Well, then stop acting as if you are running around with chips on your
 shoulders.  Behaving in such a manner is rather counter productive in
 the R community (at least from my experience/observation).  

why not read some fortunes?

When a Certain Guru rips strips off people (God knows he's done it to
me often
enough) on this list, there's a damned good reason for it.
   -- Rolf Turner (in a discussion about whether a friendly mailing list
with
  more 'customer service' attitude than R-help was needed)
  R-help (December 2003)

when gurus are ripped strips off on this list, there's a damned good
reason for it.
(and i'm actually not doing it.)  or:

You may have not been long enough on this list to see that some of the
old-time
gurus have reached a demigod like status. Demigods have all rights to be
'rude'
(that's almost a definition of a demi-deity).
   -- Jari Oksanen (in a discussion on whether answers on R-help should
be more
  polite)
  R-help (December 2004)

which certainly documents a very productive approach to communication
with users.
snip

 And what makes you believe this is not the case?   I have seen over
 the years e-mails to R-devel along the lines I am thinking of a
 change along [lots of details and reasoning for the change]; would
 patches that implement this be accepted? and these e-mails were
 discussed more often than not.  However, in the end, the only
 people who can commit changes to the R code are the members of
 R-core, thus they will have the final word of design issues (and,
 as I assume, they discuss, among other things, design issues on the
 private mailing list of R-core member).  But you can discuss this
 issues before writing a patch. 
   
 how many such mails have you seen?  
 

 A few over the years, but the more R progresses/matures the less of
 such e-mail happens.

   

a few over the years?

 i've been on r-devel for six months, and haven't seen many.  
 

 Well, six month is a rather narrow sampling window
   

your sampling window does not seem to provide better results.


   
 on the other hand, i have seen quite a few responses that were
 bashing a user for reporting a non-existent bug or submitting an
 annoying patch.
 

 In didactic terms those are negative motivations/reinforcements;
 opinion differ on how effective they are to reach certain learning
 outcomes.   
   

ah, so what's the difference between the way i pinpoint design flaws and
the way r gurus respond to people, so that i am running with a chip on
my shoulder, and they are being 'negatively motivating/reinforcing' in
didactic terms?  (am i correct, is the 'negative
motivation/reinforcement' the same stuff jari oksanen talked about?)


   
 And I am sure that if you had sent an e-mail to r-devel pointing out
 that the binary operator , when called in the non-standard way 
 ''(1,2,3), does not check the number of arguments while other
 binary operators (e.g. '+'(1,2,3) or '*'(1,2,3)) do such checks,
 and provided a patch that implemented such a check for '' (and
 presumably other comparison operators), then that patch would have
 been acknowledged and applied.
   
   
 it has been fixed immediately by martin. 
 

 Yes, and, again, you could not help yourself telling the developers
 what you think they should do, could you?  

was this really running with a chip:

shouldn't the tests have captured it? i think you should have a 

Re: [Rd] [R] are arithmetic comparison operators binary?

2009-02-24 Thread Wacek Kusnierczyk
Martin Maechler wrote:

  Thank you, Wacek, 
  though .. wrong mailing list 
  

 WK apologies.  i was actually asking for explanation, assuming that it
 WK might be my misunderstanding, rather than reporting a bug.

 ( yes; but it is really a technical topic, also touching on
   extending R [below], hence -- R-devel )
   

point taken.

 I think we'd gladly accept well-written  commented extra
   R-x.y.z/tests/foo.R  
 files or patches to existing ./tests/*.R 
 particularly if the contributor shows the new tests are
 systematically covering currently untested areas...
 Again: this really belongs to R-devel

   

ok.

 WK plus those undocumented, but assumed by the developers.

   ;-) :-)

 Indeed, we are also grateful for (concise!) patches to  man/*.Rd
 help files.
   

ok.

  If you'd looked a bit in the sources, you'd seen that they
  really are supposed to be binary only.
  

 WK it wouldn't be nonsensical to let them be of arbitrary arity (in a
 WK well-documented manner), though it might confuse users.

 Yes (to the latter).  One of the beauties of S and R is the
 syntax closeness to  mathematical notation.
 Many of us know that  Lisp  has beauties that S can never have,
 but that's really in different beauty-space. 
   

not quite sure what you mean by 'closeness to mathematical notation' here.


 WK just a question (i haven't checked the sources, maybe i should):  what
 WK is it that happens when one of the operators is called with n = 0 or 1
 WK argument?  how does it come up with logical(0) rather than NA?

 In some of the cases  e.g. 
''(1)   

 it basically does   [empty]  1  and hence returns the same as

NULL  1
   
which is consistent with NULL + 1.  btw:

1. you might want to keep the error message from applying  and other
relops to an inappropriate number of arguments in sync with the message
one gets from, e.g., '+'(1,2,3).  (you may want to actually update the
message from '+' and relatives, as it seems that there are more
operators that give an error message similar to that of ''.  the
attached patch fixes this; it has been compiled and successfully tested
-- see below.)

2. '+'() and '+'(1,2,3) say the operator needs one or two arguments, but
again, '+' is documented as a *binary* operator.  i guess the intention
here is to have them unary or binary, and it's the docs that should be
updated.

vQ


The patch for src/main/arithmetic.c was prepared as follows:

svn co https://svn.R-project.org/R/trunk/
cd trunk
tools/rsync-recommended
# modifications made to src/main/character.c
svn diff  do_grep.diff

The patched sources were successfully compiled and tested as follows:

svn revert -R .
patch -p0  do_grep.diff
./configure
make
make check



Index: src/main/arithmetic.c
===
--- src/main/arithmetic.c	(revision 47991)
+++ src/main/arithmetic.c	(working copy)
@@ -295,7 +295,7 @@
 case 2:
 	return R_binary(call, op, CAR(args), CADR(args));
 default:
-	errorcall(call,_(operator needs one or two arguments));
+	errorcall(call,_(%d arguments passed to '%s' which requires 1 or 2), length(args), PRIMNAME(op));
 }
 return ans;			/* never used; to keep -Wall happy */
 }
__
R-devel@r-project.org mailing list
https://stat.ethz.ch/mailman/listinfo/r-devel


Re: [Rd] [R] are arithmetic comparison operators binary?

2009-02-24 Thread Wacek Kusnierczyk
Wacek Kusnierczyk wrote:

 The patch for src/main/arithmetic.c was prepared as follows:

 svn co https://svn.R-project.org/R/trunk/
 cd trunk
 tools/rsync-recommended
 # modifications made to src/main/character.c
 svn diff  do_grep.diff

 The patched sources were successfully compiled and tested as follows:

 svn revert -R .
 patch -p0  do_grep.diff
 ./configure
 make
 make check

   

obviously, i forgot to replace 'do_grep' with 'arithmetic'.

vQ

__
R-devel@r-project.org mailing list
https://stat.ethz.ch/mailman/listinfo/r-devel


Re: [Rd] [R] Semantics of sequences in R

2009-02-24 Thread Dimitris Rizopoulos



Berwin A Turlach wrote:

On Tue, 24 Feb 2009 09:39:51 +0100
Wacek Kusnierczyk waclaw.marcin.kusnierc...@idi.ntnu.no wrote:


Berwin A Turlach wrote:


[...]

why not read some fortunes?

I am well aware of those fortunes and maybe you missed the one:


fortune(Watson)


Getting flamed for asking dumb questions on a public mailing list is
all part of growing up and being a man/woman.
   -- Michael Watson (in a discussion on whether answers on R-help
  should be more polite)
  R-help (December 2004)

I am actually wondering where the corresponding fortunes from December
2005, December 2006, December 2007 and December 2009 are since they
started of be produced on an annual basis.

[...]

on the other hand, i have seen quite a few responses that were
bashing a user for reporting a non-existent bug or submitting an
annoying patch.


In didactic terms those are negative motivations/reinforcements;
opinion differ on how effective they are to reach certain learning
outcomes.   
  

ah, so what's the difference between the way i pinpoint design flaws
and the way r gurus respond to people, so that i am running with a
chip on my shoulder, and they are being 'negatively
motivating/reinforcing' in didactic terms?  [...]


Your goal is, presumably, that you want to have the design flaws
fixed/discussed/c.  The goal of the R gurus is to avoid having to
waste their time on unproductive issues because people do not read
documentation/behave contrary to how they are asked to behave/c.

To reach your goal, the controversial approach is counter productive.
To reach their goal, the controversial approach can be quite effective.


in my opinion the point of the whole discussion could be summarized by 
the question, what is a design flaw? This is totally subjective, and it 
happens almost everywhere in life. Take human languages as an example 
and in particular, English. I do not know the history of the English 
language but I can guess at some point some people decided that the past 
tense for give should be gave and not gived according to the 
standard rule, possibly because they thought it has better acoustic.


Is this a design flaw of English? Some might argue yes, maybe they would 
think gived does not have a that bad acoustic or they could have come 
up with another possibility than gave. Does this confuse new users of 
English? Of course it does -- I had to spent many hours learning the 
past tense and past particle of the irregular verbs. Should it be 
changed? Then almost all existing code (i.e., English texts) should be 
rewritten, which I think demonstrates why some people are a bit 
reluctant in design changes.


To close I'd like to share with you a Greek saying (maybe also a saying 
in other parts of the world) that goes, for every rule there is an 
exception. The important thing, in my opinion, is that these exceptions 
are documented.


Best,
Dimitris



[...]
it has been fixed immediately by martin. 


Yes, and, again, you could not help yourself telling the developers
what you think they should do, could you?  

was this really running with a chip:


Look up what running with a chip on your shoulder means and reflect
on the occasions in which I suggested to you that you give the
impression of doing so.   On this occasion nobody said that you were
running around with a chip on your shoulder.


shouldn't the tests have captured it? i think you should have a check
for every feature following from the docs.

to which marting responded yes, we should


But he also made it clear that it would be unlikely that he or any
other R-core member would write those tests and that this would
probably be left to you; with any contribution being welcome.  Consider
yourself lucky that this exchange was with Martin, other members of R
core might have communicated a similar message in quite another way.
That exchange is very much confirming my understanding of the culture
of the R community.


As I try to tell you, that
is not the way it works.  R comes already with extensive tests that
are run with make check.  If you think some are missing, you
could send a script and propose that they are included.  But
telling others that they should write such tests is unlikely to
make it happen. 

haven't done the thing.


Come on, read your own quote above:  Shouldn't the tests have captured
this?  I think you should have a check for every feature following from
the docs,  If this is not telling others that they should write such
test, then what is?  


Cheers,

Berwin

__
R-devel@r-project.org mailing list
https://stat.ethz.ch/mailman/listinfo/r-devel



--
Dimitris Rizopoulos
Assistant Professor
Department of Biostatistics
Erasmus University Medical Center

Address: PO Box 2040, 3000 CA Rotterdam, the Netherlands
Tel: +31/(0)10/7043478
Fax: +31/(0)10/7043014

__
R-devel@r-project.org mailing list

Re: [Rd] [R] Semantics of sequences in R

2009-02-24 Thread Wacek Kusnierczyk
Dimitris Rizopoulos wrote:
 in my opinion the point of the whole discussion could be summarized by
 the question, what is a design flaw? This is totally subjective, and
 it happens almost everywhere in life. Take human languages as an
 example and in particular, English. I do not know the history of the
 English language but I can guess at some point some people decided
 that the past tense for give should be gave and not gived
 according to the standard rule, possibly because they thought it has
 better acoustic.

 Is this a design flaw of English? Some might argue yes, maybe they
 would think gived does not have a that bad acoustic or they could
 have come up with another possibility than gave. Does this confuse
 new users of English? Of course it does -- I had to spent many hours
 learning the past tense and past particle of the irregular verbs.
 Should it be changed? Then almost all existing code (i.e., English
 texts) should be rewritten, which I think demonstrates why some people
 are a bit reluctant in design changes.

 To close I'd like to share with you a Greek saying (maybe also a
 saying in other parts of the world) that goes, for every rule there is
 an exception. The important thing, in my opinion, is that these
 exceptions are documented.

all this is true;  however, programming languages are not natural
languages, there are substantial differences, and conclusions valid for
natural languages are not necessarily valid for programming languages.

vQ

__
R-devel@r-project.org mailing list
https://stat.ethz.ch/mailman/listinfo/r-devel


[Rd] sys.source and encoding

2009-02-24 Thread romain . francois
Hello,

The sys.source function does not have an encoding argument, and does not accept 
a connection (created by file):

gt; sys.source(syssource.R)
Error in parse(n = -1, file = file) :
 invalid multibyte character in parser at line 2

Here we could simply pass encoding or ... to parse, the next one is more 
confusing:

gt; sys.source( file( syssource.R, encoding = windows-1252 ) )
Error in sys.source(file(syssource.R, encoding = windows-1252)) :
 '5' is not an existing file

the syssource.R file contains this :

file

critère lt;- 1
/file

I can try to fix this, but maybe a decision needs to be made first about how ? 
just add the encoding argument to sys.source, add the ... to sys.source, handle 
connection in sys.source ?

gt; version
  _
platform   i686-pc-linux-gnu
arch   i686
os linux-gnu
system i686, linux-gnu
status Under development (unstable)
major  2
minor  9.0
year   2009
month  02
day08
svn rev47879
language   R
version.string R version 2.9.0 Under development (unstable) (2009-02-08 r47879)

Romain

-- 
Romain Francois
Independent R Consultant
+33(0) 6 28 91 30 30
http://romainfrancois.blog.free.fr
[[alternative HTML version deleted]]

__
R-devel@r-project.org mailing list
https://stat.ethz.ch/mailman/listinfo/r-devel


Re: [Rd] [R] Semantics of sequences in R

2009-02-24 Thread Berwin A Turlach
G'day Dimitris,

On Tue, 24 Feb 2009 11:19:15 +0100
Dimitris Rizopoulos d.rizopou...@erasmusmc.nl wrote:

 in my opinion the point of the whole discussion could be summarized
 by the question, what is a design flaw? This is totally subjective,
 and it happens almost everywhere in life. [...]

Beautifully summarised and I completely agree.  Not surprisingly,
others don't.

[...]
 To close I'd like to share with you a Greek saying (maybe also a
 saying in other parts of the world) that goes, for every rule there
 is an exception. [...]

As far as I know, the same saying exist in English.  It definitely
exist in German.  Actually, in German it is every rule has its
exception including this rule.  In German there is one grammar rule
that does not have an exception.  At least there used to be one; I am
not really sure whether that rule survived the recent reform of the
German grammar rules.

Cheers,

Berwin

__
R-devel@r-project.org mailing list
https://stat.ethz.ch/mailman/listinfo/r-devel


[Rd] [SoC09-Idea] Movement Ecology add-ons for adehabitat package

2009-02-24 Thread Damiano G. Preatoni
Hi all,
  here's a proposal for a SoC project on wildlife movement patterns analysis.
A MSc student is available to anwser the call, of course. The idea has already 
been briefly discussed with the mantainer of the adehabitat package and the 
AniMov project community.


Short description
Develop some add-on functions to use the adehabitat package to perform basic 
movement ecology analysis, in particular analysis of fractal dimension D. 
Developed functions could possibly be included in a future release of the 
adehabitat package itself.

Detailed description
Fractal dimension analysis is an useful tool to better understand not just 
the 'path tortuosity', in an animal's trajectory, but also the scale level at 
which 'search patterns' occur, i.e. an indirect index of the scale at which 
habtat resources are 'perceived'.
It has already been shown using simulations (Nams 2005; Oecologia 143: 
179-188) that the fractal dimension D of a trajectory changes within scales, 
and that the fractal dimension could be a valuable tool in multiscale 
analysis of wildlife movement patterns.
The adehabitat package, increasingly used as a free-open source alternative in 
radiiotracking and animal habitat selection studies, already has base 
functions to deal with trajectories in time and space, both as regular 
samples (e.g. data from GPS radio tags) and as irregular ones (as 
in 'classic' VHF radiotraking). The implementation of the algorithms devised 
by Nams could widen the range of analytical instruments that already make 
adehabitat an almost complete tool.
Moreover, the author of the sole existing software to do fractal analysis (V. 
O. Nams [0]) has expressed no objection towards such a porting (as reported 
by Paolo Cavallini in the AniMov mailing list [1]), suggesting that a 
complete rewrite could be a better solution.
In detail, the project objectives will be to port (or rewrite) into R 
the 'standard' methods offered by the FRACTAL program:
- fractal dimension estimation (D) using the basic divider method
- estimation of D the resampling divider method (Nams 2006: Acta Biotheoretica 
54:1-11)
- estimation of D using the VFractal estimator (Nams, 1996: Landscape Ecology 
11:289-297).
- production of other relevant movement ecology statistics useful in spetial 
scale perception by animals (Nams 2006: Animal Behaviour. 72: 1197-1203).
- optionally, in conjunction with the random movement simulators already 
present in adehabitat (in particular simm.levy and simm.crw), test for 
deviations from a CRW model (Nams and Bourgeois 2004: Can J. Zool, 
82:1738-1747) and detect if oriented movements occur (Nams 2006: Animal 
Behaviour. 72: 1197-1203)

Required skills
The candidate should be both familiar with R programming and wildlife 
radiotracking data analysis. A minimal familiarity with the adehabitat code 
could be desirable.

Mentor
Damiano G. Preatoni, PhD.
Research Associate
Unità di Analisi e Gestione delle Risorse Ambientali
Dipartimento Ambiente-Salute-Sicurezza
Università degli Studi dell'Insubria
(see signature for details)

And, finally, the programming exercise [2]:
the candidate should demonstrate to be able to transform raw irregular VHF 
radiotracking data into an adehabitat ltraj object, which could be the base 
data structure to work with in the proposed package.


[0] http://nsac.ca/envsci/staff/vnams/Fractal.htm
[1] http://www.nabble.com/fractals-to21875728.html
[2] http://xkcd.com/74/


signature.asc
Description: This is a digitally signed message part.
__
R-devel@r-project.org mailing list
https://stat.ethz.ch/mailman/listinfo/r-devel


Re: [Rd] [R] Semantics of sequences in R

2009-02-24 Thread Ted Harding
On 24-Feb-09 13:14:36, Berwin A Turlach wrote:
 G'day Dimitris,
 
 On Tue, 24 Feb 2009 11:19:15 +0100
 Dimitris Rizopoulos d.rizopou...@erasmusmc.nl wrote:
 
 in my opinion the point of the whole discussion could be summarized
 by the question, what is a design flaw? This is totally subjective,
 and it happens almost everywhere in life. [...]
 
 Beautifully summarised and I completely agree.  Not surprisingly,
 others don't.
 
 [...]
 To close I'd like to share with you a Greek saying (maybe also a
 saying in other parts of the world) that goes, for every rule there
 is an exception. [...]
 
 As far as I know, the same saying exist in English.  It definitely
 exist in German.  Actually, in German it is every rule has its
 exception including this rule.

Or, as my mother used to say, Moderation in all things!
To which, as I grew up, I adjoined  ... including moderation.
Ted.

 In German there is one grammar rule
 that does not have an exception.  At least there used to be one; I am
 not really sure whether that rule survived the recent reform of the
 German grammar rules.
 
 Cheers,
   Berwin


E-Mail: (Ted Harding) ted.hard...@manchester.ac.uk
Fax-to-email: +44 (0)870 094 0861
Date: 24-Feb-09   Time: 14:44:21
-- XFMail --

__
R-devel@r-project.org mailing list
https://stat.ethz.ch/mailman/listinfo/r-devel


Re: [Rd] [R] Semantics of sequences in R

2009-02-24 Thread Martin Maechler
 WK == Wacek Kusnierczyk waclaw.marcin.kusnierc...@idi.ntnu.no
 on Tue, 24 Feb 2009 11:31:13 +0100 writes:

WK Dimitris Rizopoulos wrote:
 in my opinion the point of the whole discussion could be summarized by
 the question, what is a design flaw? This is totally subjective, and
 it happens almost everywhere in life. Take human languages as an
 example and in particular, English. I do not know the history of the
 English language but I can guess at some point some people decided
 that the past tense for give should be gave and not gived
 according to the standard rule, possibly because they thought it has
 better acoustic.
 
 Is this a design flaw of English? Some might argue yes, maybe they
 would think gived does not have a that bad acoustic or they could
 have come up with another possibility than gave. Does this confuse
 new users of English? Of course it does -- I had to spent many hours
 learning the past tense and past particle of the irregular verbs.
 Should it be changed? Then almost all existing code (i.e., English
 texts) should be rewritten, which I think demonstrates why some people
 are a bit reluctant in design changes.
 
 To close I'd like to share with you a Greek saying (maybe also a
 saying in other parts of the world) that goes, for every rule there is
 an exception. The important thing, in my opinion, is that these
 exceptions are documented.

WK all this is true;  however, programming languages are not natural
WK languages, there are substantial differences, and conclusions valid for
WK natural languages are not necessarily valid for programming languages.

You are are right, Wacek.

However, Dimitris' comparison is still a valuable one, and I
think I know that you don't quite agree :

The S language has a long history and a relatively large user
base that goes back many years (say 20). As you know, the vast
majority are not professional programmers, not even
semi-professional ones. 
Rather  applied statisticians, scientists in many fields, also
mathematicians, most very happy about how productively they can
apply the S language by using R.
The books they have written do exist however (namely mostly collections
of R script files), and for almost all of them it would just
lead to considerable frustration if one of 
the exceptions in the language was replaced by the rule in a
way that makes their books contain typos.

We very occasionally do this, i.e., back-incompatible
improvements to R, inspite, but only rarely, when we are
convinced that the costs (user frustration, need to re-write
books) seem to be outweighed by the benefits. 

I think this is one of the big differences between (S and) R
and other computer languages you've mentioned.
So, indeed, Dimitris' parabola was more to the point than you
may have appreciated.

Hmm, but now let's return to something a bit more
productive, please...

Martin

__
R-devel@r-project.org mailing list
https://stat.ethz.ch/mailman/listinfo/r-devel


[Rd] wishlist boxplot (PR#13553)

2009-02-24 Thread ligges
[CCing Martin and Brian who had both done most svn commits of boxplot.R 
so far]


A very minor wishlist item that I should have already reported years ago:

All the time when I need presentation/publication quality boxplots, I 
add par(lend=1) in my code in order to suppress the ugly median line 
that does not stop at the end of the box given the rounded line endings.

Ugly example:

boxplot(1:10, lwd=30)



I'd like the following very minor change for boxplots:

D:\Rcompile\recent\R\src\library\graphics\Rdiff -u boxplot.R boxplot-new.R
--- boxplot.R   2009-02-24 18:04:47.265625000 +0100
+++ boxplot-new.R   2009-02-24 18:10:02.0 +0100
@@ -148,7 +148,7 @@
  ## Median
  xysegments(xP(x, -wntch), stats[3L],
 xP(x, +wntch), stats[3L],
-   lty = medlty[i], lwd = medlwd[i], col = medcol[i])
+   lty = medlty[i], lwd = medlwd[i], col = medcol[i], lend=1)
  xypoints(x, stats[3L],
   pch = medpch[i], cex = medcex[i], col= medcol[i], bg = 
medbg[i])
  ## Whiskers



Best wishes,
Uwe Ligges

__
R-devel@r-project.org mailing list
https://stat.ethz.ch/mailman/listinfo/r-devel


[Rd] invalid comparison in numeric sequence (PR#13551)

2009-02-24 Thread alexandre . courtiol
Full_Name: alex
Version: 2.8.1
OS: Ubuntu / MacOSX
Submission from: (NULL) (162.38.183.51)


 0.6==0.6
[1] TRUE
 seq(0,1,0.1)==0.4
 [1] FALSE FALSE FALSE FALSE  TRUE FALSE FALSE FALSE FALSE FALSE FALSE
 seq(0,1,0.1)==0.6
 [1] FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE
 seq(0,1,0.1)==0.8
 [1] FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE  TRUE FALSE FALSE


What is wrong with 0.6 ??? (TRUE is missing)
I tried 3 differents computers (2 Ubuntu with R 2.8.1, and one Mac with R 2.8).

__
R-devel@r-project.org mailing list
https://stat.ethz.ch/mailman/listinfo/r-devel


Re: [Rd] [R] Semantics of sequences in R

2009-02-24 Thread Mark Difford

...
My earlier email requires too much reading between the lines. This one puts
the finger more closely on the issues: There are historical inconsistencies
and there are design flaws. Naturally, there often is an overlap, but there
is also a clear area of excellence. These are largely different things and
they should not be so easily confused.

Regards, Mark.


Mark Difford wrote:
 
 Dimitris Rizopoulos wrote:
 
 in my opinion the point of the whole discussion could be summarized by
 the question, what 
 is a design flaw? This is totally subjective, and it happens almost
 everywhere in life. 
 
 This [what constitutes a design flaw, and the suggestion that all design
 flaws are subjective] needs to be more carefully defined, and cannot, or
 should not, be allowed to fly untested. People do die from time to time
 because of design flaws. In recent times, two well-known car companies had
 serious design flaws that led to several deaths.
 
 Needless to say [perhaps], design flaws in software can have serious
 consequences. So-called design flaws in a language are unlikely to. So
 there are some fundamental, and important, differences between them.
 Usually, respondents on this list are very careful not to confuse apples
 with birds, or to try to compare them.
 
 Regards, Mark.
 
 
 Berwin A Turlach wrote:
 On Tue, 24 Feb 2009 09:39:51 +0100
 Wacek Kusnierczyk waclaw.marcin.kusnierc...@idi.ntnu.no wrote:
 
 Berwin A Turlach wrote:
 
 [...]
 why not read some fortunes?
 I am well aware of those fortunes and maybe you missed the one:
 
 fortune(Watson)
 
 Getting flamed for asking dumb questions on a public mailing list is
 all part of growing up and being a man/woman.
-- Michael Watson (in a discussion on whether answers on R-help
   should be more polite)
   R-help (December 2004)
 
 I am actually wondering where the corresponding fortunes from December
 2005, December 2006, December 2007 and December 2009 are since they
 started of be produced on an annual basis.
 
 [...]
 on the other hand, i have seen quite a few responses that were
 bashing a user for reporting a non-existent bug or submitting an
 annoying patch.
 
 In didactic terms those are negative motivations/reinforcements;
 opinion differ on how effective they are to reach certain learning
 outcomes.   
   
 ah, so what's the difference between the way i pinpoint design flaws
 and the way r gurus respond to people, so that i am running with a
 chip on my shoulder, and they are being 'negatively
 motivating/reinforcing' in didactic terms?  [...]
 
 Your goal is, presumably, that you want to have the design flaws
 fixed/discussed/c.  The goal of the R gurus is to avoid having to
 waste their time on unproductive issues because people do not read
 documentation/behave contrary to how they are asked to behave/c.
 
 To reach your goal, the controversial approach is counter productive.
 To reach their goal, the controversial approach can be quite effective.
 
 in my opinion the point of the whole discussion could be summarized by 
 the question, what is a design flaw? This is totally subjective, and it 
 happens almost everywhere in life. Take human languages as an example 
 and in particular, English. I do not know the history of the English 
 language but I can guess at some point some people decided that the past 
 tense for give should be gave and not gived according to the 
 standard rule, possibly because they thought it has better acoustic.
 
 Is this a design flaw of English? Some might argue yes, maybe they would 
 think gived does not have a that bad acoustic or they could have come 
 up with another possibility than gave. Does this confuse new users of 
 English? Of course it does -- I had to spent many hours learning the 
 past tense and past particle of the irregular verbs. Should it be 
 changed? Then almost all existing code (i.e., English texts) should be 
 rewritten, which I think demonstrates why some people are a bit 
 reluctant in design changes.
 
 To close I'd like to share with you a Greek saying (maybe also a saying 
 in other parts of the world) that goes, for every rule there is an 
 exception. The important thing, in my opinion, is that these exceptions 
 are documented.
 
 Best,
 Dimitris
 
 
 [...]
 it has been fixed immediately by martin. 
 
 Yes, and, again, you could not help yourself telling the developers
 what you think they should do, could you?  
 was this really running with a chip:
 
 Look up what running with a chip on your shoulder means and reflect
 on the occasions in which I suggested to you that you give the
 impression of doing so.   On this occasion nobody said that you were
 running around with a chip on your shoulder.
 
 shouldn't the tests have captured it? i think you should have a check
 for every feature following from the docs.

 to which marting responded yes, we should
 
 But he also made it clear that it would be unlikely that he or any
 other R-core member would write those 

[Rd] Box.test reference correction (PR#13554)

2009-02-24 Thread solymos
Full_Name: Peter Solymos
Version: 2.8.1
OS: Windows
Submission from: (NULL) (129.128.141.92)


The help page of the Box.test function (stats) states that the Ljung-Box test
was published in:

Ljung, G. M. and Box, G. E. P. (1978), On a measure of lack of fit in time
series models. Biometrika 65, 553--564. 

The page numbers are incorrect. The correct citation should be as follows:

Ljung, G. M. and Box, G. E. P. (1978), On a measure of lack of fit in time
series models. Biometrika 65, 297--303. 

Yours,

Peter

__
R-devel@r-project.org mailing list
https://stat.ethz.ch/mailman/listinfo/r-devel


Re: [Rd] [R] Semantics of sequences in R

2009-02-24 Thread Mark Difford

Dimitris Rizopoulos wrote:

 in my opinion the point of the whole discussion could be summarized by
 the question, what 
 is a design flaw? This is totally subjective, and it happens almost
 everywhere in life. 

This [what constitutes a design flaw, and the suggestion that all design
flaws are subjective] needs to be more carefully defined, and cannot, or
should not, be allowed to fly untested. People do die from time to time
because of design flaws. In recent times, two well-known car companies had
serious design flaws that led to several deaths.

Needless to say [perhaps], design flaws in software can have serious
consequences. So-called design flaws in a language are unlikely to. So
there are some fundamental, and important, differences between them.
Usually, respondents on this list are very careful not to confuse apples
with birds, or to try to compare them.

Regards, Mark.


Berwin A Turlach wrote:
 On Tue, 24 Feb 2009 09:39:51 +0100
 Wacek Kusnierczyk waclaw.marcin.kusnierc...@idi.ntnu.no wrote:
 
 Berwin A Turlach wrote:
 
 [...]
 why not read some fortunes?
 I am well aware of those fortunes and maybe you missed the one:
 
 fortune(Watson)
 
 Getting flamed for asking dumb questions on a public mailing list is
 all part of growing up and being a man/woman.
-- Michael Watson (in a discussion on whether answers on R-help
   should be more polite)
   R-help (December 2004)
 
 I am actually wondering where the corresponding fortunes from December
 2005, December 2006, December 2007 and December 2009 are since they
 started of be produced on an annual basis.
 
 [...]
 on the other hand, i have seen quite a few responses that were
 bashing a user for reporting a non-existent bug or submitting an
 annoying patch.
 
 In didactic terms those are negative motivations/reinforcements;
 opinion differ on how effective they are to reach certain learning
 outcomes.   
   
 ah, so what's the difference between the way i pinpoint design flaws
 and the way r gurus respond to people, so that i am running with a
 chip on my shoulder, and they are being 'negatively
 motivating/reinforcing' in didactic terms?  [...]
 
 Your goal is, presumably, that you want to have the design flaws
 fixed/discussed/c.  The goal of the R gurus is to avoid having to
 waste their time on unproductive issues because people do not read
 documentation/behave contrary to how they are asked to behave/c.
 
 To reach your goal, the controversial approach is counter productive.
 To reach their goal, the controversial approach can be quite effective.

in my opinion the point of the whole discussion could be summarized by 
the question, what is a design flaw? This is totally subjective, and it 
happens almost everywhere in life. Take human languages as an example 
and in particular, English. I do not know the history of the English 
language but I can guess at some point some people decided that the past 
tense for give should be gave and not gived according to the 
standard rule, possibly because they thought it has better acoustic.

Is this a design flaw of English? Some might argue yes, maybe they would 
think gived does not have a that bad acoustic or they could have come 
up with another possibility than gave. Does this confuse new users of 
English? Of course it does -- I had to spent many hours learning the 
past tense and past particle of the irregular verbs. Should it be 
changed? Then almost all existing code (i.e., English texts) should be 
rewritten, which I think demonstrates why some people are a bit 
reluctant in design changes.

To close I'd like to share with you a Greek saying (maybe also a saying 
in other parts of the world) that goes, for every rule there is an 
exception. The important thing, in my opinion, is that these exceptions 
are documented.

Best,
Dimitris


 [...]
 it has been fixed immediately by martin. 
 
 Yes, and, again, you could not help yourself telling the developers
 what you think they should do, could you?  
 was this really running with a chip:
 
 Look up what running with a chip on your shoulder means and reflect
 on the occasions in which I suggested to you that you give the
 impression of doing so.   On this occasion nobody said that you were
 running around with a chip on your shoulder.
 
 shouldn't the tests have captured it? i think you should have a check
 for every feature following from the docs.

 to which marting responded yes, we should
 
 But he also made it clear that it would be unlikely that he or any
 other R-core member would write those tests and that this would
 probably be left to you; with any contribution being welcome.  Consider
 yourself lucky that this exchange was with Martin, other members of R
 core might have communicated a similar message in quite another way.
 That exchange is very much confirming my understanding of the culture
 of the R community.
 
 As I try to tell you, that
 is not the way it works.  R comes already with extensive tests that