Displaying 20 results from an estimated 5000 matches similar to: "A problem about outer()"
2012 Jun 18
6
Trying to speed up an if/else statement in simulations
Dear R-help,
I am trying to write a function to simulate datasets of size n which contain
two time-to-event outcome variables with associated 'Event'/'Censored'
indicator variables (flag1 and flag2 respectively). One of these indicator
variables needs to be dependent on the other, so I am creating the first and
trying to use this to create the second using an if/else statement.
2008 Dec 17
1
Asterisk 1.4 to AS5400 using H.323 (ooh323) inbound working but outbound doesn't
I have the following setup: DS3 -> Cisco AS5400 -> H.323 (ooh323) ->
Asterisk
Inbound calls work great but outbound calls fail. So to check and
make sure we have outbound calling ability on the DS3 we setup a Cisco
Call Manager Express and it can make outbound calls both local and
long distance with no problems.
The failure code is Cause i = 0x8381 - Unallocated/unassigned number.
We
2014 Oct 22
1
display force off - kernel 3.18
http://cgit.freedesktop.org/~darktama/nouveau/commit/?id=4d60422
also broken with this commit
2009 Nov 29
3
Plotting observed vs. Predicted values, change of symbols
Dear Wiz[R]ds,
I am deeply grateful for the help from Duncan Murdoch, Gray Calhoun, and
others. We are almost there. For whatever reason, I can't change the symbol
from a circle to a triangle in the upright posture plots. Any ideas? I have
included the problem in full.
# tritiated (3H)-Norepinephrine(NE) disappearance from plasma
# concentrations supine and upright
# supine
datasu <-
2018 May 03
4
adding overall constraint in optim()
Hi ?
This is giving me a headache. I?m trying to do a relatively simple optimization ? actually trying to approximate the output from the Excel Solver function but at roughly 1000x the speed. ?
The optimization parameters look like this. The only trouble is that I want to add a constraint that sum(wgt.vect)=1, and I can?t figure out how to do that in optim.
Mo.vect <-
2006 Sep 04
3
Subsetting vectors based on condition
Hello,
I have a question regarding subsetting of vectors. Here's an example of
what I'm trying to do:
vect.1 <- c(76,195, 290, 380)
vect.2 <- c(63, 95, 133, 170, 215, 253, 285, 299, 325, 375)
I would like to subset vect.2 so that it has the same length as vect.1,
and its numbers are the first corresponging higher value compared to
vect.1.
The output should be:
final.output =
2003 Nov 14
7
Vector indices and minus sign
Hi,
I got caught out by this behaviour in 1.8.0 and I wondered why this
happens:
I have a list of vectors and was using lapply and grep to remove
matched elements that occur in only a subset of the elements of the
list:
locs <- lapply(locs, function(x){x[- grep("^x", x)]})
The problem is that where the grep finds no matches and hence returns a
vector of length 0, all the
2018 May 03
2
adding overall constraint in optim()
Thanks Bert. But everyone on that forum wants to use finance tools rather than general optimization stuff! And I am not optimizing a traditional Markowitz mean-variance problem. Plus, smarter people here. :-)
> On May 3, 2018, at 3:01 PM, Bert Gunter <bgunter.4567 at gmail.com> wrote:
>
> You can't -- at least as I read the docs for ?optim (but I'm pretty
> ignorant
2011 Feb 13
6
From numeric vector to string vector
Hi there, I have a numeric vector let say:
Vect <- c(12.234, 234.5675, 1.5)
Now I want a string vector like:
changedVec <- c("012.234", "234.568", "001.500")
Would be grateful if somebody help me how can I do that.
Thanks and regards,
[[alternative HTML version deleted]]
2008 Jun 09
1
Cross-validation in R
Folks; I am having a problem with the cv.glm and would appreciate someone
shedding some light here. It seems obvious but I cannot get it. I did read
the manual, but I could not get more insight. This is a database containing
3363 records and I am trying a cross-validation to understand the process.
When using the cv.glm, code below, I get mean of perr1 of 0.2336 and SD of
0.000139. When using a
2001 Nov 05
1
Why doesn't outer work?
Hello
I'm a population ecologist and use R for all my stats and modelling.
Recently I have been using R to numerically solve integral projection
models. This involves constructing several large matrices. The current code
by Easterling (Size-specific sensitivity: Applying a new structured
population model. Ecology, 2000, 81, 694-708) uses nested loops to construct
the matrices. To speed up the
2012 Dec 11
1
Rprof causing R to crash
I'm trying to use Rprof() to identify bottlenecks and speed up a particullary
slow section of code which reads in a portion of a tif file and compares
each of the values to values of predictors used for model fitting. I've
written up an example that anyone can run. Generally temp would be a
section of a tif read into a data.frame and used later for other processing.
The first portion
2012 Mar 17
3
rtriang using ifelse statement
Hi All,
I want to draw samples (n=4) from one of 2 triangular distributions for
each value in a matrix. I am using an ifelse statement to try to define
which distribution to draw from.
>From the output, I can see that the ifelse statement is choosing the correct
distribution, however, my n=4 simulations aren't occurring. Is there a way
to adjust the ifelse statement to fix this, or must
2018 May 04
0
adding overall constraint in optim()
On Thu, May 3, 2018 at 2:03 PM, Michael Ashton
<m.ashton at enduringinvestments.com> wrote:
> Thanks Bert. But everyone on that forum wants to use finance tools rather than general optimization stuff! And I am not optimizing a traditional Markowitz mean-variance problem. Plus, smarter people here. :-)
>
I'm very confused by these statements. Most of the "finance tools"
2009 Apr 16
2
error bars in matplot
Hi,
I was trying to get error bars in my matplot. I looked at an earlier thread, and the sample code that I made is:
#------------------
library(plotrix)
mat1 <- matrix(sample(1:30,10),nrow=5,ncol=2)
ses <- matrix(sample(1:3,10,replace=T),nrow=5,ncol=2)
vect <- seq(20,100,20)
rownames(mat1) <- rownames(ses) <- vect
colnames(mat1) <- colnames(ses) <- letters[1:2]
2018 May 06
1
adding overall constraint in optim()
Hi Michael,
A few comments
1. To add the constraint sum(wgt.vect=1) you would use the method of
Lagrange multipliers.
What this means is that in addition to the w_i (the components of the
weight variables) you would add an additional variable, call it lambda.
Then you would modify your optim.fun() function to add the term
lambda * (sum(wgt.vect - 1)
2. Are you sure that you have defined
2018 May 03
0
adding overall constraint in optim()
You can't -- at least as I read the docs for ?optim (but I'm pretty
ignorant about this, so maybe there's a way to tweak it so you can).
See here: https://cran.r-project.org/web/views/Optimization.html
for other R optimization capabilities.
Also, given your credentials, the r-sig-finance list might be a
better place for you to post your query.
Cheers,
Bert
Bert Gunter
2009 Aug 04
2
can a key of a list be a variable
Hi,
I search a solution to record data in dynamic structures in R.
I have an algorithm that will be executed each step and whose output is an
array of doubles with unknown size.
The solution I found is to use lists
1) I initialise my list
l <- list()
2) and at a step numbered i I conacatain the new tab to the list
vect <- algorithm()
l <<--c( l , list(stepi=vect))
The problem is
2018 May 05
1
adding overall constraint in optim()
Hi,
You can use the projectLinear argument in BB::spg to optimize with linear equality/inequality constraints.
Here is how you implement the constraint that all parameters sum to 1.
require(BB)
spg(par=p0, fn=myFn, project="projectLinear", projectArgs=list(A=matrix(1, 1, length(p0)), b=1, meq=1))
Hope this is helpful,
Ravi
[[alternative HTML version deleted]]
2007 Aug 10
2
need help to manipulate function and time interval
Hi R-users,
I have to define a noise level function L and its energy in the various
moment of the day by:
if time is between 18:00:00 and 23:59:59 then L[j] <- L[j]+5 and W <-
10^((L+5)/10)
if time is between 22:00:00 and 05:59:59 ==> L <- L+10 and W <-
10^((L+10)/10)
else
L=L and W = W
Could someone help me to realize this function please? You will find my
following