Displaying 20 results from an estimated 6000 matches similar to: "help on R primitives"
1997 Sep 25
2
R-beta: return()
I have a question on the use of return(). (Nothing on it in the docs I
have)
The test code below gives the error: Error: Object "x" not found
when I do: thingy2().
How should it be fixed? Thanks very much for any help!
(My original solution to this sort of problem was to use global variables
x<<-...
y<<-...)
Bill Simpson
-----------------------------
thingy<-function(k)
1998 Sep 03
2
ppoints
When I look at ppoints I see:
ppoints<-function (x)
{
n <- length(x)
if (n == 1)
n <- x
(1:n - 0.5)/n
}
However Venables & Ripley (2nd ed, p 165) say ppoints() should return
(i-1/2)/n for n>=11; (i-3/8)/(n+1/4) for n<=10.
The version below should work as described:
ppoints<-function (x)
{
n <- length(x)
if (n <= 10)
(1:n - 0.375)/(n + 0.25)
else
(1:n - 0.5)/n
1998 Jan 07
1
R-beta: image
Questions on image:
1) How can I put labels on the x and y axes?
2) How to tell it to use e.g. 32 grey levels (not some colour map)?
3) How to know what the legend is (i.e. each grey level = what z value)?
Thanks very much for any help.
BTW I was wondering if persp was on the To Do list. That would be great!
Bill Simpson
1998 Feb 26
3
R-beta: quantile
I do:
x<-rnorm(1000)
quantile(x,c(.025,.975))
2% 98%
-1.844753 1.931762
Since I want to find a 95% confidence interval, I take the .025 and .975
quantiles. HOWEVER R says I have the 2% (not 2.5%) and 98% (not 97.5%)
points. Is it just rounding the printed 2% and 98%, or is it REALLY
finding .02 and .98 points instead of .025 and .975?
Thanks for any help.
Bill Simpson
1998 Feb 26
3
R-beta: quantile
I do:
x<-rnorm(1000)
quantile(x,c(.025,.975))
2% 98%
-1.844753 1.931762
Since I want to find a 95% confidence interval, I take the .025 and .975
quantiles. HOWEVER R says I have the 2% (not 2.5%) and 98% (not 97.5%)
points. Is it just rounding the printed 2% and 98%, or is it REALLY
finding .02 and .98 points instead of .025 and .975?
Thanks for any help.
Bill Simpson
1998 Mar 25
1
R-beta: qpois help
version .62:
---------------------------------------------
> ?qpois
The Poisson Distribution
dpois(x, lambda)
ppois(q, lambda)
qpois(p, lambda)
rpois(n, lambda)
Arguments:
x: vector of (positive) quantiles.
p: vector of probabilities.
n: number of random values to return.
lambda: vector of positive means.
1998 Apr 03
1
R-beta: default paper size
After some paper clipping problems I checked options() and saw that the
default paper size was a4; I need US Letter. So as per instructions I
uncommented the R_PAPERSIZE line in config.site,
R_PAPERSIZE=letter
Restarting R, everything is still the same though. I guess I have to
reinstall?
That seems awkward. Is there a way a prompt ("a4 or letter paper?") can
be inserted in the
1998 Apr 13
1
R-beta: command line editing?
I would love to have bash-like command line editing in R. (Press up cursor
and see previous command line; use left cursor to go back then edit it)
Appendix B in Rnotes describes Splus I guess, not R. Starting R by
R -e
doesn't let any of the following described actions (B.3) work.
I don't use vi or EMACs (I use Nedit), so I would prefer bash-like
interface anyway. (I don't think I
1998 Jan 16
1
R-beta: kill R Graphics window->crash R
I am running R-0.61.1 on linux under X. If I kill the R Graphics window
(click on X box in upper right corner), then subsequently do x11(),
R crashes.
I find that things only work the right way if I close the graphics window
using dev.off().
I was wondering if maybe it could be arranged that closing the graphics
window via click would seem to R to be equivalent to typing dev.off().
BTW thanks
1998 Jul 03
1
R-beta: histogram
Can someone please tell me to make a density histogram?
hist makes one with count or relative frequency on the y-axis.
I want the density, which is (rel freq)/(bin width)
In the help I see:
intensities: values f^(x[i]), as estimated density values.
If `all(diff(breaks) == 1)', they are the relative
frequencies `counts/n' and in general satisfy
1998 Jul 03
1
R-beta: sum of squares and NAs
This surprised me. Is it the way it is supposed to be?
> x<-c(1,2,3,4,5)
> y<-c(1.2,1.3,1.4,1.5,NA)
> x-y
[1] -0.2 0.7 1.6 2.5 NA
> (x-y)^2
[1] 0.04 0.49 2.56 6.25 NaN
>>>so NA^2 = NaN? Why not still NA?
> sum((x-y)^2)
[1] NaN
>>>yes that is reasonable
So if you ever have a data set with missing observations (NAs), you can't
do any nlm() least
1998 Jul 13
1
R-beta: accessing SEs from lm object
If I do
fit<-lm(y~x)
Is it possible to access the SE of the slope?
(Analogous to getting the slope like this: fit$coef[2])
If not, it would be handy.
(I want SE of 1/slope, and an approx way is fit$se[2]/(fit$coef[2]^2))
Thanks for any help.
Bill Simpson
-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-
r-help mailing list -- Read
1998 Jun 25
1
R-beta: re-appearing workspace
I am using R Version 0.62.0 Unstable-snapshot (April 26, 1998)
on Linux. I use the AfterStep window manager.
Problem. Once upon a time, a workspace was saved. But at the end of
this session, on quitting R I say "no", don't save workspace.
On starting up, there are all the old objects again!
I take it that the workspace is saved as ~/.RData.
So is the only solution to manually rm
1998 Mar 11
1
R-beta: ms, nls, etc?
I tried to ?ms, ?nls and apparently these aren't implemented on R yet.
However I seem to remember postings on this list having to do with fitting
nonlinear models (no I don't mean GLM type fits, I have a REAL nonlinear
model: y=ax^b + c). So please tell me if it is possible to fit nonlinear
models in R (by least squares or ML).
Thanks!
Bill Simpson
1998 Apr 01
1
line plot with NA
I have the following data:
intens<-c(28000,72000,120000,150000,180000,260000,310000) #Td
peakcb<-c(1.2,2.5,2.7,3.7,5.6,6.2,6.8) #presses/s
peakan<-c(0.5,3.7,5.1,5.8,7.4,NA,8.4)
(See why I am using NA? I can work around this problem by using
intensityan and intensitycb)
Now do a plot of peakan:
plot(intensity, peakan, pch=10,type="b")
The plot skips the point (260000,NA),
1998 Sep 02
1
INSTALL
I just installed R 0.62.3 and it seems to me the INSTALL document is out
of date. Now it seems it does it all "automatically", so the part in the
doc below can be deleted:
--------------------------------
INSTALLATION
After
./configure
make
have been completed successfully, you can install the complete R tree
to your system by typing
make install
...
1998 Mar 06
1
R-beta: image saved ps file
I include the argument
pty="s"
to image, but still when I make an image by the method
> postscript("rstuff/test.ps")
> tauseq<-seq(0,1,.5)
> cif2d.image(x,,y,tauseq)
> dev.off()
the image plot created is NOT square. I thought pty="s" would make it
square.
Generally it would be nice if the image saved to disk were like the one we
see while in R
1998 Jan 12
2
R-beta: first view, then save plot or image?
I know how to first set postscript output, then execute plot or image
command to create a postscript file of a plot or image.
I was wondering if it is possible to first create the plot or image on
screen so it can be viewed, THEN save it to file? Without doing plot() or
image() again?
(I ask because I have a complicated image computation that takes about 1-2
hrs to complete. I would like to
1998 Mar 12
2
R-beta: nonlinear fitting
Thanks very much Douglas for the pointer to nlm.
Maybe the "Notes on R" maintainer can add at least a mention of nlm in the
section on nonlinear fitting?
I never did nonlinear fitting in S-Plus before, so I have nothing to
unlearn, but I was hoping someone could show me how to do a least squares
fit with nlm.
example:
x<-c(1,2,3,4,5,6)
y<-.3*x^-.6 +.2
y<-y+rnorm(6,0,.01)
1998 Mar 12
2
R-beta: nonlinear fitting
Thanks very much Douglas for the pointer to nlm.
Maybe the "Notes on R" maintainer can add at least a mention of nlm in the
section on nonlinear fitting?
I never did nonlinear fitting in S-Plus before, so I have nothing to
unlearn, but I was hoping someone could show me how to do a least squares
fit with nlm.
example:
x<-c(1,2,3,4,5,6)
y<-.3*x^-.6 +.2
y<-y+rnorm(6,0,.01)