Displaying 20 results from an estimated 11000 matches similar to: "List of multidimensional arrays"
2012 Oct 04
3
Problem with colors in contour plot
Dear R users,
I have a 51 by 51 matrix of p-values (named as pvalue_MA). I want to
present graphically this matrix in a plot (filled contour plot) where both
axes represent probabilities. I have also added a grid in this plot. I want
to highlight in white the cells of the grid that represent p-values smaller
than the (common) significance threshold, 0.05. The code from this plot is
colored in
2012 Oct 28
2
List of arrays - problem with dimensions
Dear all,
I want to obtain the following result
[[1]]
, , 1, 1
[,1] [,2]
[1,] 1 1
[2,] 1 1
, , 2, 1
[,1] [,2]
[1,] 1 1
[2,] 1 1
................
, , 9, 1
[,1] [,2]
[1,] 1 1
[2,] 1 1
, , 10, 1
[,1] [,2]
[1,] 1 1
[2,] 1 1
[[2]]
, , 1, 1
[,1] [,2]
[1,] 1 1
[2,] 1 1
, , 2, 1
[,1] [,2]
[1,] 1
2012 Oct 02
2
Problem with mutli-dimensional array
I want to make a multi-dimensional array. To be specific I want to make the
following array
results<-array(0,dim=c(2,2,64,7))
This is the code I have created but it gives no result due to the error
"subscript out of bound".
x<-rep(7,7) # Missingness in intervention
y<-rep(7,7) # Missingness in control
2012 Sep 26
1
Creating x*y different contigency tables
Dear all,
I am trying to construct 25x31 different matrices of 2x2 dimension. Here
is the problem:
we have the following matrix
matrix(c(54+s0,
43+s1, 56-s0, 67-s1), nrow=2, ncol=2, byrow=T)
the values for s0 and s1 are c(0:24) and c(0:31), respectively.
I wrote the following code without the desired results
2012 Nov 08
1
A panel of contour plots through a iteration process
Dear all,
as you can see from the code I want to create *a panel of 11 contour
plots through
a iteration process*. I found a thread that address the issue of plotting
many contour.plots in the same device, but it does not address my problem!
I emphasize that the 11 contour plots must be appeared in the same device
through an iteration process and NOT individually!
par(mfrow=c(4,3)) # I want them
2011 Feb 14
1
Analyzing dissimilarity ratings with Multidimensional Scaling
Dear R-list members,
I need an help with the Multidimensional Scaling analysis (MDS).
So far I used the cmdscale() command in R, but I did not get the perceptual
map I would love to see,
and I would like to know if it is possible to get it using R, and if yes
how.
I also had a look to the functions isoMDS() and sammoc() but with no luck.
I summarize the experiment I performed, and I would ask you
2007 Sep 26
1
Repeated tests against baseline
I came across a post by Karl Knoblick regarding the modeling of longitudinal data (see https://stat.ethz.ch/pipermail/r-help/2007-May/132137.html). I am often asked by physicians to perform what Karl refers to in his post as option 1: to perform paired t-tests against baseline at each follow up time point (30 days, 90 days, 6 months, etc.). Unlike Karl's example, however, many of the trials
2009 Feb 27
2
Adjusting confidence intervals for paired t-tests of multiple endpoints
Dear R-users,
In a randomized placebo-controlled within-subject design, subjects recieved
a psycho-active drug and placebo. Subjects filled out a questionnaire
containing 15 scales on four different time points after drug
administration. In order to detect drug effects on each time point, I
compared scale values between placebo and drug for all time conditions and
scales, which sums up to
2010 Jul 22
1
gam() and contrast
Dear All,
I met problems when doing contrast and now really need some help in the
model below:
Fit=gam(y~treat+SEQUENCE+PERIOD+SEX+s(x),data=dat,
random=list(SUBJID=~1),correlation=corAR1(form=~1|SUBJID))
And error message keeps coming out when I want to compare the differences
between treatments:
Diff=contrast(Fit,
list(treat=treatment[-placebo.pos]),list(treat="Placebo"),
2012 May 14
3
How to apply a function to a multidimensional array based on its indices
Hello. I have a 4 dimensional array and I want to fill in the slots with
values which are a function of the inputs. Through searching the forums here
I found that the function "outer" is helpful for 2x2 matrices but cannot be
applied to general multidimensional arrays. Is there anything which can
achieve, more efficiently than the following code, the job I want?
K <-
2004 Feb 05
2
Incomplete Factorial design
Hello,
I am planning a study with the main point to evaluate the interaction of two treatments,
but for ethical reasons one cell is empty, that with patients receaving no treatment at all
Treatment B
2011 Mar 01
1
glht() used with coxph()
Hi, I am experimenting with using glht() from multcomp package together with
coxph(), and glad to find that glht() can work on coph object, for example:
> (fit<-coxph(Surv(stop, status>0)~treatment,bladder1))
coxph(formula = Surv(stop, status > 0) ~ treatment, data = bladder1)
coef exp(coef) se(coef) z p
treatmentpyridoxine -0.063 0.939 0.161
2006 Sep 27
3
multidimensional lists
In the process of moving a number of my scripts from MATLAB -> R, I've
discovered that there is no 'pure' equivalent of MATLAB's cell arrays,
which I use quite often. Basically, I create matrices (as a cell array)
where each element of the matrix is itself a matrix (e.g., 2x2 cell
array where each element of the array is another matrix). I pass these
cell arrays to various
2011 May 13
2
L'abbe plot
I cannot seem to get a L'abbe plot to work on R. I do not understand what
the X coordinates, or alternatively an object of class metabin, is
supposed to mean. What is a class of metabin?
Institute of Behavioral Genetics
University of Colorado, Boulder
Whitney.Melroy at Colorado.EDU
2002 Apr 19
4
Multidimensional scaling
A student of mine wants to use R to do some nonmetric multidimensional
scaling. According to the R FAQ, there's a package called pcurve that
computes multidimensional scaling solutions, but I was not able to locate
it the contrib page (I am a Windows user with R version 1.4.1). Can
anyone tell me whether it is possible to do nonmetric multidimensional
scaling with R, and if so, how?
John
2010 Jul 01
2
Export data frame of high dimension to txt
I managed with success to export a data frame of 367 columns and 37 rows to a txt file, but unfortunately I couldn't manage the same with the transposed data frame. Specifically, it seems like the notebook cannot "read" correctly 367 columns, so it reads the first 145 columns and it folds down the rest of them and consequently it folds down the respective data.
2010 Mar 02
2
ANOVA "Types" and Regression models: the same?
Hello,
I think I am beginning to understand what is involved in the so-called
"Type-I, II, ..." ANOVAS (thanks to all the replies I got for yesterday's
post). I have a question that will help me (and others?) understand it
better (or remove a misunderstanding):
I know that ANOVA is really a special case of regression where the
predictor variable is categorical. I know that there
2008 Feb 01
2
the "union" of several data frame rows
Hi,
I have a question about how to obtain the union of several data frame
rows. I'm trying to create a common key for several tests composed of
different items. Here is a small scale version of the problem. These
are keys for 4 different tests, not all mutually exclusive:
id q1 q2 q3 q4 q5 q6
1 A C
2 B D
3 A D B
4 C D B D
I would like
2006 Jul 11
2
Multiple tests on 2 way-ANOVA
Dear r-helpers,
I have a question about multiple testing.
Here an example that puzzles me:
All matrixes and contrast vectors are presented in treatment contrasts.
1. example:
library(multcomp)
n<-60; sigma<-20
# n = sample size per group
# sigma standard deviation of the residuals
cov1 <- matrix(c(3/4,-1/2,-1/2,-1/2,1,0,-1/2,0,1), nrow = 3, ncol=3, byrow=TRUE,
dimnames =
2006 Jul 17
1
multiplying multidimensional arrays (was: Re: [R] Manipulation involving arrays)
I am moving this to r-devel.
The problem and solution below posted on r-help could have been
a bit slicker if %*% worked with multidimensional arrays multiplying
them so that if the first arg is a multidimensional array it is mulitplied
along the last dimension (and first dimension for the second arg).
Then one could have written:
Tbar <- tarray %*% t(wt) / rep(wti, each = 9)
which is a bit