Displaying 20 results from an estimated 5000 matches similar to: "finding "clusters" in 2-dimensional data"
2004 Jun 21
6
Visual stimulus presentation using R?
Dear all!
Although the Psycho-Toolbox for Matlab is free software, Matlab isn't.
I'm planning to do an experiment where it's essentail to travel to the
subjects, not let the subjects come to where the Matlab licences are
:-(
So I need to use a free software for my experiment if I don't want to
by an extra Matlab licence (which I don't want to).
Did anyone ever try to do
2008 Jul 28
2
Help with a loop
HI:
I need ideas on how to make this code shorter (maybe with a second loop?).
The code as it is works, but in this case I only have 14 samples, but it
will become insane with more, so I need a way to make it more automatic. The
problem is that the output from ts1, ts2, and so on is a vector with more
than one value, so I do not know how to solve this.
Thanks
Prenewbie
The code is the
2011 Jun 17
0
Inconsistent results from var.get.nc in RNetCDF
Hello -
I am having trouble extracting data from NetCDF data files using
RNetCDF. The data files each have 3 dimensions (longitude, latitude,
and a date) and 3 variables (latitude, longitude, and a climate
variable).
Here is some of the output from print.nc for clarity:
-----
dimensions:
month = UNLIMITED ; // (1368 currently)
lat = 3105 ;
lon = 7025 ;
variables:
float
2005 Jan 17
0
[basic ?] Merging result of by processing with a data fra me
> From: Jean-Louis Abitbol
>
> Dear All,
>
> I would like to merge a data frame such as:
>
> > basetab
> subject dose cmax
> 1 1031 50 21.8
> ....
>
> with the result of a by processing such as:
>
> > tmax<-by(pkga,subject,f.tmax)
> > tmax
> subject: 1031
> [1] 6
> --------------------------------------------------
2005 Jan 31
2
coercing a list to a data frame, lists in foreloops
I have a set of time-series climate data with missing entries. I need to add
rows for these missing entries to this data set. The only way I know to do
this is unsing a foreloop, but this won't work on a list. I've tried to
convert the list to a data frame, but that won't happen, either.
I want to fill rows in this table:
> newtest[10:15,]
yrmos yearmo snow.sum snow.mean
2011 Aug 08
0
Re: Tmax Window(a propietary OS) using Wine?
Forgive my poor English.
There is Tmax Window, the 1st windows XP compatible proprietary OS from Korea.
Tmax company showed screenshot of Tmax Windows.
But it is known as they mixed images with real XP and OpenOffice suite screenshots.
http://mr-dust.pe.kr/entry/Tmaxwindow-screenshot-failed
Tmax Window is doubtful about stolen ReactOS source code:
This is a post of a tmax developer.
2007 Oct 25
0
Error message from nlmer
Hi,
I have R 2.6.0 with updated lme4 and Matrix packages, and I am trying to
fit a nonlinear multilevel model. I get the following error message:
Error in nlmer(f ~ grModel(x, w, Tmin, Tmax, Topt, kopt, m) ~ kopt |
flat, :
gradient attribute of evaluated model must be a numeric matrix
and I wonder what this may indicate.
The nonlinear model I try to fit is as follows:
> grModel
2013 Apr 24
0
Understanding how nls() works
I'm trying to understand what goes on in the process that nls() uses.
This converges without much drama:
> rate.nls <- nls(Dev ~ exp(rho * (T)) - exp(rho*Tmax - (Tmax - T)/del)+
+ lam , data = xx, trace = TRUE,
+ start = c(rho = 0.15, del = 7, lam = .02, Tmax = 30))
599.7841 : 0.15 7.00 0.02 30.00
4.69849 : 0.14673457 6.83443060 -0.01417782
2003 Dec 17
1
repeated measures aov problem
Hi all,
I have a strange problem and rigth now I can't figure out a
solution.
Trying to calculate an ANOVA with one between subject factor (group)
and one within (hemisphere). My dependent variable is source
localization (data). My N = 25.
My data.frame looks like this:
> ML.dist.stack
subj group hemisphere data
1 1 tin left 0.7460840
2 2 tin left
2015 Sep 04
0
getting a vector of unown size
Hi all!
I have written some code in C for simulating the fate of population
using a dll loaded in R. During this simulation the population may go
extinct such that the length of its trajectory is unknown beforehand. I
wonder there is a way to define the size of the result in C and make it
known to R to get the vector appropriately.
I have defined the output size very much larger than
2007 Oct 23
0
API for optimization with Simulated annealing
Dear list,
I was trying to use the R API for optimization method "Simulated annealing"
void samin(int n, double *x, double *Fmin, optimfn fn, int maxit,
int tmax, double temp, int trace, void *ex);
but I encountered the following problem:
The implementation of the function samin (as seen in src/main/optim.c)
passes its void * argument "ex" into the function
2004 Sep 06
1
A naive lsoda question....
Hello,
I am an R newbie, trying to use lsoda to solve standard
Lotka-Volterra competition equations. My question is: how do I
pass a parameter that varies with time, like say, phix <- 0.7 +
runif(tmax) in the example below.
# defining function
lotvol <- function(t,n,p){
x <- n[1]; y <- n[2]
rx <- p["rx"]; ry <- p["ry"]
Kx <-
2016 Apr 20
1
Use multiple cores on Linux
I am trying to run the following code in R on a Linux cluster. I would like
to use the full processing power (specifying cores/nodes/memory). The code
essentially runs predictions based on a GAM regression and saves the
results as a CSV file for multiple sets of data (here I only show two).
Is it possible to run this code using HPC packages such as
Rmpi/snow/doParallel? Thank you!
2009 Nov 17
1
How to plot an image in R
Dear all
Im new in R
I have a necdf data set that I want to plot :
this is my data set
[1] "file Tmax.DJF.daily.1981_1999.echama2.nc has 4 dimensions:"
[1] "longitude Size: 127"
[1] "latitude Size: 110"
[1] "ht Size: 1"
[1] "t Size: 1680"
[1] "------------------------"
[1] "file Tmax.DJF.daily.1981_1999.echama2.nc has 1
2012 Sep 20
3
Line over Boxplot
Very much a rookie at R, and have only recently started using it again so
pardon the simple question. I am trying to produce a box plot from one data
set and then overlay a line plot from another data set. The box plot data
set is made up of 20 sets of 30 data points, or 600 total data points. The
line has only 30 total data points. The box plot is plotting fine, but for
some reason, the line plot
2003 Feb 21
0
Linear mixed effects models
Hi everyone,
I'm a newbie to R and to linear mixed effects modeling, so please have mercy
:-)
Just wanted to check, whether what I'm doing is alright.
I've collected data concerning tonotopic organization of the auditory cortex
in humans, and I have approximately 1400-1800 data/time points per person
(13 in total). Observations were made how the focus of neuronal activity
changed
2008 Oct 08
1
Error in spdep: system is computationally singular
Hi all,
I am trying to run an autologistic model using the function errorsarlm from spdep package.
**I built an XY matrix extracting the two colums from matriz**
coords1<-matriz[matriz$casos1==1, c(4,5)]
coords1<-as.matrix(coords1)
**I identify neighbours of region points**
nb20<-dnearneigh(coords1,0,20,longlat=TRUE)
** I build a neighbours list with spatial weights**
2012 Mar 19
3
Issue with asin()
Hello everyone,
I am working for a few days already on a basic algorithm, very common in
applied agronomy, that aims to determine the degree-days necessary for a
given individual to reach a given growth stade. The algorithm (and context)
is explained here: http://www.oardc.ohio-state.edu/gdd/glossary.htm , and
so I implemented my function in R as follows:
DD <- function(Tmin, Tmax, Tseuil,
2010 Jul 26
2
Concatenate a mix of numbers and letters to create a vector name
Dear all,
I am trying to create a vector name, for example tmax.195012 from tmax., 1950 and 12. Obviously I don't wish to simply type it because the 3 name components are changing in each iteration within a loop. Is there any way of concatenating those 3 components (which are a mixture of numbers and letters)?
Thanks for reading,
Panos
2002 Jun 18
1
remote rsync process dies, local hangs
I've got an rsync job which is consistently failing, but I've been
unable to diagnose the problem. FAQ/Google/docs/etc. checked and
no luck.
Basically, it looks like the rsync process invoked on the far end
is exiting, and then the local process waits until the timeout and
exits.
Both systems are Sun boxes, Ultra 10 or better with 256+ MB of memory.
Rsync version is 2.5.0 on the local