Displaying 20 results from an estimated 3000 matches similar to: "Zero rows/cols in the hessian matrix"
2004 Feb 19
1
Obtaining SE from the hessian matrix
Dear R experts,
In R-intro, under the 'Nonlinear least squares and maximum likelihood
models' there are ttwo examples considered how to use 'nlm' function.
In 'Least squares' the Standard Errors obtained as follows:
After the fitting, out$minimum is the SSE, and out$estimates are the
least squares estimates of the parameters. To obtain the approximate
standard
2004 Jan 21
2
derivative of atan(x) and similar functions
Dear R experts.
'D()' function recognizes some of the analitical functions, such as
sin, cos, etc. But I'd like to take analytical derivatives from asin,
atan etc. functions. Are there any R packages providing that features?
Thanks.
--
Timur.
2003 Aug 01
2
'format' problem
Dear R experts,
format(12345678, digits = 2)
gives
[1] "1.2e+07"
while
format(1234567, digits = 2)
gives
[1] "1234567"
but I'd like the last number to be represented as "1.2e+06" string too.
Where am I wrong?
Thanks,
Timur.
2005 Aug 16
2
Registration with Asterisk server
Dear Asterisk community,
sorry if I'm so stupid, but I couldn't register myself with Asterisk.
I created the [sip-incoming] context in the sip.conf:
[sip-incoming]
type = peer
username = elzhov
port = 5062 ; my kphone listens port 5062
host = 127.0.0.1
Then run Asterisk, and checked peers that are known for Asterisk:
*CLI> sip show peers
Name/username
2003 Oct 30
2
'nls' and its arguments
Dear R experts!
I'd to fit data by 'nls' with me-supplied function 'fcn'.
1) I'd like 'fcn' to accept arbitrary arguments, i.e. I defined it
as f(...) {<body>}. (Ok, that's not actually impotant).
2) Second, I would NOT like to supply every parameter in the formula.
To illustrate this, let's look at the last example of 'nls' help
2002 Dec 06
2
Fitting 2D vs. 2D data with nls()
Dear R-experts!
I have y(x) data, dim(y) == dim(x) == c(2000, 2)
I'd like to fit them with nls:
fit.result <- nls ( y ~ f(x, p1, p2, p3),
start = list(p1 = ... , p2 = .. , p3 = ..)
)
Actually I want to fit y[,1] ~ x[,1] and y[,2] ~ x[,2]
*simulaneously*, with the same parameters set {p1, p2, p3}.
I tried to feed R tha above formula, R errors with:
2003 Jan 17
1
Arguments of R- and C-side of internal functions
Dear R experts,
I looked at the body of, say, `optim' function and found
the call to the `.Internal', C optim function. It looks
like this:
.Internal(optim(par, fn1, gr1, method, con, lower, upper))
On the other hand, the C prototype of optim is:
SEXP do_optim(SEXP call, SEXP op, SEXP args, SEXP rho);
So, I guess that all the list of parameters passing in R are assigned
to
2003 Nov 12
1
problem with x11 and PS devices on different machines
Dear R help,
I run R at home and the work, I have Debian Linux on both machines and
the same 'r-base-core' deb packages installed. So I tried to run the
same R script, which plots graph in x11 device and then dump it to eps
file (x11 and eps you'll find attached). On the home machine there are
some stranges in x11 plot as well as in eps file. On the work machine
all the ok, despite
2004 Mar 15
8
Simple numeric "as.is" question
I am reading a list of numbers from my clipboard, and have been
successful, except I can't make a histogram as R doesn't recognize my
variable as numeric. I know I need to use "as.is", but the specifics
escape me.
I have used x<-read.table("clipboard", header=F) to import from a txt
file. How do make this numeric? Thanks, J.
2004 Nov 09
4
R code debugging
Dear useRs,
it's quite difficult for me to find `Error:'s in my R code, because R does
say about error itself, but say nothing about its location, say, string
number and file with an error (which may be `source'd from another file).
Are there any option for turning of the similar feature, or R can not do
such a thing at all?
Thanks.
--
WBR,
Timur.
2004 Feb 03
5
lm coefficients
Dear R experts,
Excuse me if my question will be stupid...
I'd like to fit data with x^2 polynomial:
d <- read.table(file = "Oleg.dat", head = TRUE)
d
X T
3720.00 4.113
3715.00 4.123
3710.00 4.132
...
out <- lm(T ~ poly(X, 4), data = d)
out
Call:
lm(formula = T ~ poly(X, 2), data = d)
Coefficients:
(Intercept) poly(X, 2)1 poly(X, 2)2
2004 May 21
2
.First() in R 1.9.0
Dear R experts,
I just upgraded R from 1.8.1 to 1.9.0 version. My .First()
function in ~/.Rprofile contains x11() and par() functions.
.First <- function() {
x11(display = "", 8.0, 5.0)
par(las = 1, ...)
## ...
}
And, R claims now, on startup:
[hello messages skiped ...]
Error in .First() : couldn't find function "x11"
>
I commented
2005 Jul 22
1
asterisk captures sound device
Hello, dear Asterisk experts.
When I run Asterisk (CVS HEAD version), I'm not able to play music
anymore -- asterisk seems to capture sound device. Is it not a bug,
but a feature? That's unlike stable (1.0.7 and 1.0.9) versions, when
I can, say, run an IP telephone on the *same* machine and listen what
Asterisk' autoattendant says. Now I can't do that, I need Asterisk
and client
2009 Jun 18
1
ogg_stream_reset() question
Hi Ogg experts!
My current work is catenating packets from several ogg files to the
one long stream, so I'd like to create stream once, and then reset it
just before reading codec headers from every new file. However, after
calling
ogg_stream_reset_serialno(ogg_stream_state *os, int serialno),
bos page is not pushed in stream since it calls
ogg_stream_reset(ogg_stream_state *os),
which
2002 Dec 20
1
GetRNGstate() crashes with 'Segmentation fault'
Dear R-masters,
I tried to compile this simpel C-code:
//-----------------
#include<R.h>
int main()
{
GetRNGstate();
return 0;
}
//-----------------
Compiling:
~> gcc -o a a.c -I/usr/lib/R/include/ -L/usr/lib/R/bin/ -lR
~> ldd a
libR.so => /usr/lib/libR.so (0x40018000)
libc.so.6 => /lib/libc.so.6 (0x401a8000)
libblas.so.2 =>
2003 Jan 13
1
Evaluating expressions from within C code
Dear R experts!
I want to evaluate expressions from within C code. For instance,
I want this code:
/* ============ -- C code -- ============== */
#include <R.h>
#include <Rinternals.h>
SEXP foo(SEXP expr, SEXP rho)
{
SEXP x;
PROTECT(x = allocVector(REALSXP, 1));
REAL(x)[0] = 1;
UNPROTECT(1);
return
2003 Feb 25
1
Error analysis
Dear R experts,
I fitted data (length == m) with an external library (that's
a non-linear problem), and, I've got the final parameter vector
(length == n) and Jacobian matrix (dim == c(m, n)). Now, I want
to analyse the standard errors of the parameters correctly.
How can I do it?
Where can I read about it else?
Thanks!
--
WBR,
Timur.
2003 Jun 01
1
persp & colors
Dear R experts!
I use image() & persp() functions for color plotting z(x,y)-type
graphics. In image() colors correspond to z-values, that's what
I want. OTOH, in persp() the col option means:
col: the color(s) of the surface facets. Transparent colours are
ignored. This is recycled to the (nx-1)(ny-1) facets.
but I'd like to persp()' colors behave like in
2005 Jul 25
1
Voicemail: could not stop recording
Dear friends,
please excuse me if my question will be trivial.
I've installed and started Asterisk (stable 1.0.7, but with CVS HEAD
I experienced just the same problem), and changed a bit sip.conf:
[general]
; ...
dtmfmode = inband
disallow = all
allow = ulaw
allow = alaw
allow = gsm
run kphone, and call the 1235 extension. According to sample
extensions.conf, Asterisk would
2008 Sep 10
3
making spearman correlation cor() call fail with log(0) as input
Hi,
How can I make the cor(x, y, method="spearman") call to produce an
error when the input to it (x, y) produces an error? Here is a simple
example:
> a <- c(0, 1, 2)
> b <- c(100, 2, 4)
## error:
> log(a)
[1] -Inf 0.0000000 0.6931472
## error, as expected:
> cor(log(a), log(b), method="pearson")
[1] NaN
## not an error any more (not expected):
>