Displaying 20 results from an estimated 4000 matches similar to: "concatenating column names in a loop"
2011 Feb 17
4
Find and replace all the elements in a data frame
Hi all,
I'm having a problem once again, trying to do something very simple. Consider
the following data frame:
x <- read.table(textConnection("locus1 locus2 locus3
A T C
A T NA
T C C
A T G"), header = TRUE)
closeAllConnections()
I am trying to make a new data frame, replacing "A" with "A/A", "T" with "T/T",
"G" with
2018 Feb 02
1
R-gui sessions end when executing C-code
Hi
I'm trying to develop some C code to find the fixpoint of a contraction mapping, the code compiles and gives the right results when executed in R.
However R-gui session is frequently terminated. I'm suspecting some access violation error due to the exception code 0xc0000005
In the error report windows 10 gives me.
It is the first time I'm writing any C-code so I'm guessing I
2011 Nov 15
1
Estimating model parameters for system of equations
Hi all,
I'm trying to estimate model parameters in R for a pretty simple system of
equations, but I'm having trouble. Here is the system of equations (all
derivatives):
eqAlgae <- (u_Amax * C_A) * (1 - (Q_Amin / Q_A))
eqQuota <- (p_max * R_V) / (K_p + R_V) - ((Q_A-Q_Amin)*u_Amax)
eqResource <- -C_A * (p_max * R_V) / (K_p + R_V)
eqSystem <- list(C_A = eqAlgae, Q_A = eqQuota,
2010 Oct 06
2
Pointing to a specific place on the x-axis with an arrow
Hi all,
I am trying to do something simple, but which is deviling me. I want to add an
up-arrow to the x-axis, pointing to a specific location on the axis. I want the
arrow to be as large as possible.
Here is where I'm at with my code:
#this part if from the ?plot example:
require(stats)
plot(cars)
lines(lowess(cars))
#I am trying to use mtext to add the arrow... but I don't know how
2007 Apr 12
1
LME: internal workings of QR factorization
Hi:
I've been reading "Computational Methods for Multilevel Modeling" by Pinheiro and Bates, the idea of embedding the technique in my own c-level code. The basic idea is to rewrite the joint density in a form to mimic a single least squares problem conditional upon the variance parameters. The paper is fairly clear except that some important level of detail is missing. For
2011 Jul 08
1
computing functions with Euler's number (e^n)
I am trying to create a set of wavelets in frequency space--namely Cauchy
wavelets for an intensity analysis (von Tscharner, 2000). The wavelets are
defined by the following formula:
[(f/cf)^(cf*scale)]*[e^((-f/cf)+1)^(cf*scale)]
where *f *is frequency of length *n*, *cf* is center frequency (defined
below) and is an array of *j *columns and *n* row, and scale is a constant.
cf = (1/scale)*(j
2009 Apr 13
3
toupper does not work in sub + regex
Hi, I don't know what I am doing wrong to the toupper does not seem
working in sub + regex. The following returns 's' not the upper class
'S' as I expect:
sub("q_([a-z])[a-zA-Z]*",toupper('\\1'),"q_sviRaw")
Can someone tell me where I did wrong?
Thanks,
Richard
[[alternative HTML version deleted]]
2010 Sep 16
3
Help with customizing a histogram figure
Hi all,
Please consider the following code:
require(plotrix)
l <- list(rnorm(50),rnorm(50,sd=2),rnorm(50,mean=3))
multhist(l)
I have two things I need help with:
(1) In the output, there are empty spaces on the x-axis. How would I eliminate
these spaces? I want a nice, smooth, empty-spaceless x-axis.
(2) How could I add tracing lines to each histogram? I am undoubtedly using the
wrong
2011 Apr 11
2
Plotting a quadratic line on top of an xy scatterplot
Dear Listserv,
Here is my latest in a series of simple-seeming questions that dog me.
Consider the following data:
x <- read.table(textConnection("temperature probability
0.11 9.4
0 2.3
0.38 8.7
0.43 9.2
0.6 15.6
0.47 8.7
0.09 12.8
0.11 9.4
0.01 7.7
0.83 8
0.65 9.3
0.05 7.4
0.34 10.1
0.02 4.8
0.07 9.1
0.6 15.6
0.01 8.4
0.9 9.6
0.83 8
0.12 8.4
0.01 8
0 5
0.11 9.7
0.41 7.4
0.05 9.4
0.09
2010 Sep 26
2
Splitting a data frame into several completely separate data frames
Hello again,
How do I split a data frame into smaller, completely separate data frames
(rather than separate data frames comprising a single "list")? Consider the
following data, and my coding attempt:
x <- read.table(textConnection("id type number
indv.1 bagel 6
indv.2 bagel 1
indv.3 donuts 10
indv.4 donuts 9"), header = TRUE)
closeAllConnections()
x.split <-
2005 Apr 27
0
Fitting a kind of Proportional Odds Modell using nlme, polr, lrm or ordgee
Hello,
I'm trying to fit a special kind of proportional odds model from:
Whitehead et al. (2001). Meta-analysis of ordinal outcome using
individual patient data. Statistics in medicine 20: 2243-2260. (model 2)
The data are as follows:
library(nlme)
library(geepack)
library(Design)
library(MASS)
options(contrasts=c("contr.SAS","contr.poly"))
counts <-
2007 Apr 12
0
LME: internal workings of QR factorization --repost
Hi:
I've been reading "Computational Methods for Multilevel Modeling" by Pinheiro and Bates,
the idea of embedding the technique in my own c-level code. The basic idea is to rewrite
the joint density in a form to mimic a single least squares problem conditional upon the
variance parameters. The paper is fairly clear except that some important level of detail
is missing. For
2010 Jun 09
2
Change the name of one column ONLY
Hi all,
I have a very simple problem that I cannot seem to find the answer to. Consider the following toy dataset:
x <- read.table(textConnection("V1 apples bananas cherries
indv.1 7 8 4 3
indv.2 7 7 4 9"), header = TRUE)
How would I change the column name of ONLY the first column, not the others? Surely I should not have to re-specify the names of ALL the columns -- e.g.,
2008 Aug 20
4
Looping over groups
Hello,
My R skills are somewhere between novice and intermediary, and I am hoping that some of you very helpful forum members, whom I've seen work your magic on other peoples' problems/questions, can help me here.
I have a matrix with the following format:
(i) individual plants comprising many different genotype groups (i.e., a plant is genotype 1 or genotype 2 or genotype 3, etc). The
2011 Feb 20
3
Partial italic in graph titles when looping
Dear all,
I have a rather complicated problem. I am trying to loop through making graphs,
so that the graph-making process is fully automated. For each graph, I'd like to
make sure the corresponding title is formatted properly. The titles will be a
combination of a gene name and numerical position within the gene. The gene name
should be italic-bold, whereas the gene position should be
2005 Jan 29
7
Sipura SPA-841 auto-answer support [patch]
Sipura has implemented auto-answer in version 0.9.5 of the SPA-841
firmware. However, it is implemented via the Call-Info header, which
Asterisk stable doesn't currently support.
The attached patch implments a quick hack to support the Call-Info
header from the Dial() application by way of setting the CALL_INFO
variable. For example, the following macro can be used to dial up a
single
2011 Nov 12
1
State space model
Hi,
I'm trying to estimate the parameters of a state space model of the
following form
measurement eq:
z_t = a + b*y_t + eps_t
transition eq
y_t+h = (I -exp(-hL))theta + exp(-hL)y_t+ eta_{t+h}.
The problem is that the distribution of the innovations of the transition
equation depend on the previous value of the state variable.
To be exact: y_t|y_{t-1} ~N(mu, Q_t) where Q is a diagonal
2007 Apr 14
6
[LLVMdev] Regalloc Refactoring
On Thu, 12 Apr 2007, Fernando Magno Quintao Pereira wrote:
>> I'm definitely interested in improving coalescing and it sounds like
>> this would fall under that work. Do you have references to papers
>> that talk about the various algorithms?
>
> Some suggestions:
>
> @InProceedings{Budimlic02,
> AUTHOR = {Zoran Budimlic and Keith D. Cooper and Timothy
2010 Mar 13
2
Indexing a matrix within loops
Hi,
I was hoping someone could help me with the following problem. Consider this toy example. For the input dataset there are four individuals (rows "indv.1" through "indv.4"), measured for two different variables (columns "var.1" and "var.2") at two different levels of a factor (column "factor.level"). I want to calculate a matrix that has the
2013 Nov 02
2
[PATCH] curve25519-sha256@libssh.org key exchange proposal
Am 02.11.2013 um 11:38 schrieb Aris Adamantiadis <aris at 0xbadc0de.be>:
> RFC4251 describes mpint to be multi-size and with positive values having
> MSB clear, so it's clearly incompatible with raw string.
>
> Since you both agreed on the curve25519 implementation to use, I'll work
> today on Markus' patch to make the changes Damien wanted.
What do you want to