Displaying 20 results from an estimated 11000 matches similar to: "aliases (PR#6614)"
2004 Mar 29
1
Help Documentation (PR#6717)
Ivo,
Let me address your points in reverse order:
1. There is a `wishlist' category for bug reports, which I guess you've
overlooked.
2. There is also a `Contributed Documentation' section on the R web site,
which you can submit your contribution. As well, there are a few
introductory level documents there already that you might be interested.
3. I must repectfully disagree about
2004 Mar 27
2
exit() and stop() documentation (PR#6706)
Full_Name: ivo welch
Version: any
OS: linux
Submission from: (NULL) (130.132.33.212)
hi: in "?stop", in "See Also", please add "quit()" as a mention. Similarly, I
would create a help for ?exit, which simply states that "you are probably
looking for quit() or stop()".
regards,
/ivo
2004 Mar 29
3
Help Documentation
I think many people share your view and are aghast at the
reception that some well-intentioned posts receive. There
have been past discussions on this and many people feel the
way you and I do.
Just to head off another round, let me acknowledge that
there appears to be multiple viewpoints and although hard
to believe by myself, there actually is a contingent that
views what I see as
2004 Jul 07
3
fast NA elimination ?
dear R wizards: an operation I execute often is the deletion of all
observations (in a matrix or data set) that have at least one NA. (I
now need this operation for kde2d, because its internal quantile call
complains; could this be considered a buglet?) usually, my data sets
are small enough for speed not to matter, and there I do not care
whether my method is pretty inefficient (ok, I
2004 Jun 20
4
if syntax
I ran into an interesting oddity of R,
if (0) { print(1); }
else { print(2); }
is a syntax error, while
if (0) { print(1); } else { print(2); }
or
if (0) { print(1);
} else { print(2); }
is not. I presume it has to do with the duality of the newline
functioning as an end of command (;) character, though it still seems a
bit odd, and it took me a while to figure out
2011 Jul 02
2
speeding up perception
Dear R developers: R is supposed to be slow for iterative
calculations. actually, it isn't. matrix operations are fast. it is
data frame operations that are slow.
R <- 1000
C <- 1000
example <- function(m) {
cat("rows: "); cat(system.time( for (r in 1:R) m[r,20] <-
sqrt(abs(m[r,20])) + rnorm(1) ), "\n")
cat("columns: "); cat(system.time(for (c
2004 Mar 28
1
add "select" to subset docs (PR#6710)
Full_Name: ivo welch
Version: current
OS: linux
Submission from: (NULL) (130.132.33.212)
* In the ?subset page, please add
subset( dataframe, select= c(-column1,-column2) )
returns a dara frame that is without columns 1 and 2 .
* Also, in ?lm, it would be nice to add a few more words about how to get a
residuals vector of the same length as the variable vectors, even if there
2004 Mar 26
8
stop() vs. error() ?
Why does stop("we are done") print
"Error in eval.with.vis(expr, envir, enclos) :" ?
It would seem to me that a plain stop() is not an error, and that it
would make more sense to have an error() function that is different from
a stop(). Is there a rationale here that I am missing?
sincerely, /iaw
2013 Feb 06
5
First R Package --- Advice?
Dear R experts---
after many years, I am planning to give in and write my first R
package. I want to combine my collection of collected useful utility
routines.
as my guide, I am planning to use Friedrich Leisch's "Creating R
Packages: A Tutorial" from Sep 2009. Is there a newer or better
tutorial? this one is 4 years old.
I also plan on one change---given that the
2012 Mar 30
4
list assignment syntax?
Dear R wizards: is there a clean way to assign to elements in a list?
what I would like to do, in pseudo R+perl notation is
f <- function(a,b) list(a+b,a-b)
(c,d) <- f(1,2)
and have c be assigned 1+2 and d be assigned 1-2. right now, I use the clunky
x <- f(1,2)
c <- x[[1]]
d <- x[[2]]
rm(x)
which seems awful. is there a nicer syntax?
regards, /iaw
----
Ivo Welch
2012 May 09
2
big quasi-fixed effects OLS model
dear R experts---now I have a case where I want to estimate very large
regression models with many fixed effects---not just the mean type, but
cross-fixed effects---years, months, locations, firms. Many millions of
observations, a few thousand variables (most of these variables are
interaction fixed effects). could someone please point me to packages, if
any, that would help me estimate such
2012 May 31
2
print.data.frame to string?
dear R experts---is there a function that prints a data frame to a string?
cat() cannot handle lists, so I cannot write cat("your data frame is:\n",
df, "\n").
regards, /iaw
----
Ivo Welch (ivo.welch@gmail.com)
[[alternative HTML version deleted]]
2010 Jan 08
4
fast lm se?
dear R experts---I am using the coef() function to pick off the coefficients
from an lm() object. alas, I also need the standard errors and I need them
fast. I know I can do a "summary()" on the object and pick them off this
way, but this computes other stuff I do not need. Or, I can compute (X'
X)^(-1) s^2 myself. Has someone written a fast se() function?
incidentally, I think
2013 Feb 07
4
Hard Stop?
is it possible to throw a stop() that is so hard that it will escape
even tryCatch?
/iaw
----
Ivo Welch (ivo.welch at gmail.com)
2012 Dec 24
2
parallelized version of "by" and "ave"
Dear R experts---
Has anyone written parallel versions of "by" (i.e., mcby) and "ave"
(i.e. mcave) ? I did ask a question like this a year ago, and then
the answer was no.
for those who are googling the group for the answer to this question,
in the meantime, the poor man's version of "by" is mclapply( split(
ds, factor ), FUN )
I don't know the poor
2010 Jun 11
3
lm without error
this is not an important question, but I wonder why lm returns an
error, and whether this can be shut off. it would seem to me that
returning NA's would make more sense in some cases---after all, the
problem is clearly that coefficients cannot be computed.
I know that I can trap the lm.fit() error---although I have always
found this to be quite inconvenient---and this is easy if I have only
2011 Oct 10
5
multicore by(), like mclapply?
dear r experts---Is there a multicore equivalent of by(), just like
mclapply() is the multicore equivalent of lapply()?
if not, is there a fast way to convert a data.table into a list based
on a column that lapply and mclapply can consume?
advice appreciated...as always.
regards,
/iaw
----
Ivo Welch (ivo.welch at gmail.com)
2010 Aug 22
2
on abort error, always show call stack?
Dear R Wizards---is it possible to get R to show its current call
stack (sys.calls()) upon an error abort? I don't use ESS for
execution, and it is often not obvious how to locate how I triggered
an error in an R internal function. Seeing the call stack would make
this easier. (right now, I sprinkle "cat" statements everywhere, just
to locate the line where the error appears.) Of
2011 May 15
4
"Low Pain" Unicode Characters in pdf graph?
Dear R-experts---is there a relatively low-pain way to get unicode
characters into a plot to a pdf device?
pdf(file="cardsymbols.pdf")
plot( 0, xlim=c(0,5), ylim=c(0,5), type="n")
text(1,1, "♠")
text(2,2, "♥")
text(3,3, "♦")
text(4,4, "♣")
dev.off()
(these are the characters that I need the most
2010 Aug 20
3
Date Inconsistencies? Buglets?
The treatment of dates seems to be a little inconsistent in R 2.11.1
(2010-05-31):
[1] The choice of origins?
> as.integer(as.Date("1970-01-01"))
works and assumes as origin 1970-01-01. However,
> as.Date(1)
does not work. It requires an origin (as.Date(1,
origin="1970-01-01")). If we set a default origin in the former, it
should probably work when the input