Displaying 20 results from an estimated 10000 matches similar to: "discriminant function analysis"
2013 May 13
2
reduce three columns to one with the colnames
Ein eingebundener Text mit undefiniertem Zeichensatz wurde abgetrennt.
Name: nicht verf?gbar
URL: <https://stat.ethz.ch/pipermail/r-help/attachments/20130513/fe848ce7/attachment.pl>
2013 Jun 18
2
find closest value in a vector based on another vector values
Dear All,
would you please provide your thoughts on the following:
let us say I have:
a <-c(1,5,8,15,32,69)
b <-c(8.5,33)
and I would like to extract from "a" the two values that are closest to the values in "b", where the length of this vectors may change but b will allways be shorter than "a". So at the end based on this example I should have the result
2012 Sep 12
3
Need help
Hello,
I am brand new in this site as well as in R. Please accept my early apology if it's not the right place to ask such a question.
I have the following equation:
b=[2(1-a)(1+2a)^0.5]/(1+3a)
How can I solve the above equation for 'a' using R?
Thanks in advance.
KD
[[alternative HTML version deleted]]
2012 Jul 23
3
How to do the same thing for all levels of a column?
Dear all,
I am a R beginner, and I am looking for a way to do the same thing for all
levels of a column in a table.
Basically, I have a bunch of protein sequences composed of different amino
acid residues, and each residue is represented by an uppercase letter. I
want to calculate the ratio of different amino acid residues at each
position of the proteins. Here is an example table:
Proteins
2013 Mar 09
2
grouping followed by finding frequent patterns in R
I have a data in the following form :
CIN TRN_TYP
9079954 1
9079954 2
9079954 3
9079954 4
9079954 5
9079954 4
9079954 5
9079954 6
9079954 7
9079954 8
9079954 9
9079954 9
. .
. .
. .
there are 100 types of CIN (9079954,12441087,15246633,...) and respective
TRN_TYP
first of all, I want this data to be
2012 Feb 23
5
cor() on sets of vectors
suppose I have two sets of vectors: x1,x2,...,xN and y1,y2,...,yN.
I want N correlations: cor(x1,y1), cor(x2,y2), ..., cor(xN,yN).
my sets of vectors are arranged as data frames x & y (vector=column):
x <- data.frame(a=rnorm(10),b=rnorm(10),c=rnorm(10))
y <- data.frame(d=rnorm(10),e=rnorm(10),f=rnorm(10))
cor(x,y) returns a _matrix_ of all pairwise correlations:
cor(x,y)
2012 Oct 11
3
Sorting a data frame by specifying a vector
Hello all,
I cannot seem to figure out this seemingly simple procedure.
I want to sort a data frame by a specified character vector.
So for :
df.. <- data.frame(Season=rep(c("Summer","Fall","Winter","Spring"),4),Obs=
runif(length(rep(c("Summer","Fall","Winter","Spring"),4))))
I want to sort the data frame
2012 Sep 27
1
Problem with grid.rect
I have a stupid problem that is currently driving me crazy...
Let us suppose that I want to draw a big red square in the middle of my
current device (say X11)
I tried the following code :
pushViewport(viewport(xscale=c(0,1), yscale=c(0,1)), just=c("center", "center"))
vp1 <- viewport(x=unit(0.5, "native"), y=unit(0.5, "native"),
width=unit(0.4,
2012 Sep 25
3
(core) designation on Task View
Hello,
Does the (core) designation in the CRAN Task View indicate packages
that provide basic/recommended functionality in that domain?
I don't see it documented anywhere on the site.
Thanks for your help.
2012 Sep 01
2
(Newbie) help cannot find chrome
Following the beginning tutorial, I typed help.start() and was given a
choice of browsers. I picked chrome but got back that chrome is not found.
I cannot seem to change or get rid of it now.
I looked at /etc/R/Renviron but don't see anywhere to set browser
(R_BROWSER = ${R_BROWSER ...etc) - nothing about chrome.
I tried starting as "R_BROWSER= R" - same thing.
How do I change the
2012 Jan 11
2
2D filter in R?
Hi all,
I am looking for a command for doing 2D filtering (rectangular or
Gaussian) in R...
I have looked at ksmooth, filter and convolve but they seem to be 1D...
Any thoughts?
Thanks a lot!
[[alternative HTML version deleted]]
2011 Oct 11
2
replicate data.frame n times
Hi,
is there a way to replicate a data.frame like you can replicate the entries of a vector (with the repeat-function)?
I want to do this:
x <- data.frame(x, x)
(where x is a data.frame).
but n times.
And it should be as cpu / memory efficient as possible, since n is pretty big in my case.
thanks for any suggestions!
2013 Feb 28
4
Iteration through a list in R
Hello :)
I'm just starting out with R and would appreciate your help with a couple
of problems I am running into.
I have used Sys.glob to get a list of all filenames having a particular
file extension (in my case, *.txt)
I would now like to use this list in the following manner: I would like to
use each filename from the list and open that file into a tab separated
matrix and proceed.
How can
2013 Apr 05
1
Reversing data transformation
Hi everybody,
I would be very grateful if you could give me your thoughts on the following issue.
I need to perform Box-Cox (bcPower) transformation on my data. To do this, I calculated lambda using the function 'powerTransform'.
powerTransform(data)
However, I got an error message when performing this function:
Convergence failure: return code = 52
I was told by John Fox
2012 May 04
2
Off-Topic: Crime Statistics Don't Pay
WARNING: COMPLETELY OFF TOPIC -- Nothing to do with R.
I thought readers of this list might enjoy the following. The link to
the full article is at the bottom. I hope this is not "too"
inappropriate.
-------
Overconfidence in crime statistics doesn?t pay. In a new study, a team
of criminologists makes the case that reported crime rates should
acknowledge uncertainty in the data. The
2013 Jan 11
3
looking for R packages that can do the following:
1. Minimum Mean Square Estimation (for Multi-Dimensional Linear Regression)
2. Two-Sample Kolmogorov-Smirnov Tests
3. Empirical ANOVA Methods
All this to be done on empirical data.
I am new to the R world, any help would be appreciated.
Thank You,
Bill Gilliland
Lead Sensor Systems Engineer
E303, Tactical Communications, Transport, and Sensors
Group: Tactical
2013 Apr 20
1
Assigning factor to character vector
Hi!
Yesterday I accidentally discovered this:
> a <- LETTERS[1:5]
> a
[1] "A" "B" "C" "D" "E"
>
> a[1] <- factor(a[1])
> a
[1] "1" "B" "C" "D" "E"
BUT:
> b <- factor(LETTERS[1:5])
> b
[1] A B C D E
Levels: A B C D E
> b[1] <- factor(b[1])
> b
[1] A B C D E
2012 May 02
2
selection by two unique variables
Dear Group,
I am working with a large dataset where I need to select for each unique id
the the unique lastpk row. Here is a sample subject:
id wtdt wt lastpk
64050256 2010-09-18 275 2010-09-16
64050256 2010-09-19 277 2010-09-18
64050256 2010-09-20 272 2010-09-18
64050256 2010-09-21 277 2010-09-18
I want the result as:
2013 Jun 17
2
SVMREF infinte number of genes
dear all,
I am a student in cs college. I would like to know how to plot infinte
number of genes after using the svm.
the data set i have consists of
x which is a matrix of 39 cancer patients [rows] and 2000 gene names
[colmns]. each cell is the value of the gene for a particular patient.
there are two types of cancer people representedas factor y.
here is the code:
library(e1071)
#load
2013 Mar 05
2
Questions on implementing logistic regression
Hi there,
I am trying to write a tool which involves implementing logistic
regression. With the batch gradient descent method, the convergence is
guaranteed as it is a convex problem. However, I find that with the
stochastic gradient decent method, it typically converges to some random
points (i.e., not very close to the minimum point resulted from the batch
method). I have tried different ways