[R] two questions for R beginners

Claudia Beleites cbeleites at units.it
Fri Feb 26 18:29:08 CET 2010


Dear Patrick (and all)

I'm now working with R a couple of years, before working mostly in Matlab
Lazy & impatient is both true for me :-)

> * What were your biggest misconceptions or
> stumbling blocks to getting up and running
> with R?

 > * What documents helped you the most in this
 > initial phase?
 >
 > I especially want to hear from people who are
 > lazy and impatient.
 >
 > Feel free to write to me off-list.  Definitely
 > write off-list if you are just confirming what
 > has been said on-list.
 >

Stumbling:

* It took me long to remember
getwd () and setwd () (instead of pwd and cd / chdir or the like)

* I still discover very useful functions that I would have needed for a long 
time. Latest discoveries: mapply and ave
I knew aggregate. And was always a little angry that it needs a grouping list. I 
even decided that the aggregate method for my hyperSpec class should work with 
factors as well as with lists. Some day I read in this mailing list that ave 
does what I need...
I like the crosslinks in the help (see also) very much. Maybe I rely too much on 
them. So: not lazy today, I attach a patch for aggregate.Rd that adds the 
seealso to ave.

Reading this mailing list once in a while gives me nice new ideas. However, > 50 
emails / d is somewhat scary for me, so I read only occasionally.

* Vecorization: I like the *apply functions.
but I'd really appreciate a comprehensive page/vignette here.
I remember that it took me a while to realize that the rule for MARGIN in sweep 
is "use the same number as in the apply that created the STATS"

* I never found the pdf manuals helpful (help pages are easier to access, and 
there is nothing in the pdf that the help doesn't have.
At the beginning I expected the pdf manual to be something that the vignettes are.

* I did not arrive at a comfortable debugging cycle for a long time. But now 
there's the debug package and setBreakpoint and I'm happy....

* As I now start teaching I notice that many students react to error messages 
"uhh! an error!" (panic). Few realizing that the error message actually gives 
information on what went wrong.
A list with common causes of different error messages would be helpful here, I 
think.
In case someone agrees: I started one at the Wiki: 
http://rwiki.sciviews.org/doku.php?id=tips:errormessages


Cheers,

Claudia





More information about the R-help mailing list