Displaying 20 results from an estimated 3000 matches similar to: "data(eurodist) and PCA ??"
2009 Aug 13
1
eurodist example dataset is malformed
The eurodist dataset (my favorite for mds) is malformed. Instead of a
standard distance matrix, it's a data frame. The rownames have gotten
'bumped' to a new anonymous dimension "X". It's possible to fix the data,
but it messes up a lot of example code out there.
X Athens Barcelona Brussels Calais ...
1 Athens 0 3313 2963 3175
2 Barcelona
2004 Jun 29
2
Several PCA questions...
Hi, I am doing PCA on several columns of data in a data.frame.
I am interested in particular rows of data which may have a particular
combination of 'types' of column values (without any pre-conception of
what they may be).
I do the following...
# My data table.
allDat <- read.table("big_select_thresh_5", header=1)
# Where some rows look like this...
# PDB SUNID1
2010 Nov 19
1
library(datasets)
## i have one question anouth this package..
library(datasets)
eurodist
## if i type this i get max distance between european cities
> max(eurodist)
[1] 4532
## but i would like get something like this: 4532 Gilbratar - Anthens
## and another one..
## if a live in barcelona and i would like travel in all cities
## how can i get sum of all distance to other cities... i try
2008 Jun 17
4
PCA analysis
Hi,
I have a problem with making PCA plots that are readable.
I would like to set different sympols instead of the numbers of my samples or their names, that I get plotted (xlabs).
How is this possible? With points, i don´t seem to get the right data plotted onto the PCA plot, as I do not quite understand from where it is taken. I dont know how to
plot the correct columns of the prcomp
2008 Jun 27
1
plotting prcomp
Please consider the following PCA example;
my.df <-
data.frame(A=(x <- rnorm(100,mean=100, sd=10)),
B=(y <- x + rnorm(100,mean=10, sd=10)))
plot(my.df)
my.pc <-
prcomp(my.df, center=TRUE, scale=TRUE)
biplot(my.pc)
my.x <- (my.pc$x)[,1]
my.y <- (my.pc$x)[,2]
plot(my.x, my.y, type="n")
text(my.x, my.y, labels=1:100)
Clearly the plots have the same
2004 Nov 04
4
highly biased PCA data?
Hello, supposing that I have two or three clear categories for my data,
lets say pet preferece across fish, cat, dog. Lets say most people rate
their preference as being mostly one of the categories.
I want to do pca on the data to see three 'groups' of people, one group
for fish, one for cat and one for dog. I would like to see the odd person
who likes both or all three in the
2020 Apr 25
5
[PATCH] Allow RDTSC and RDTSCP from userspace
On Sat, Apr 25, 2020 at 1:23 PM Joerg Roedel <joro at 8bytes.org> wrote:
>
> On Sat, Apr 25, 2020 at 12:47:31PM -0700, Andy Lutomirski wrote:
> > I assume the race you mean is:
> >
> > #VC
> > Immediate NMI before IST gets shifted
> > #VC
> >
> > Kaboom.
> >
> > How are you dealing with this? Ultimately, I think that NMI will need
2005 Oct 11
1
Manual page example of plot.window needs fixing
I was looking at the example on the manual page of plot.window, and
noticed that it needs fixing - names(eurodist) should now be
labels(eurodist):
--- /home/rsb/topics/R-2.2.0/src/library/graphics/man/plot.window.Rd
2005-04-18 12:18:59.000000000 +0200
+++ plot.window.Rd 2005-10-11 21:08:57.000000000 +0200
@@ -48,6 +48,6 @@
ry <- range(y <- -loc[,2])
plot(x, y, type="n",
2010 Apr 02
2
Biplot for PCA using labdsv package
Hi everyone,
I am doing PCA with labdsv package. I was trying to create a biplot graphs
in order to observe arrows related to my variables. However when I run the
script for this graph, the console just keep saying:
*Error in nrow(y) : element 1 is empty;
the part of the args list of 'dim' being evaluated was:
(x)*
could please someone tell me what this means? what i am doing
2011 May 13
2
biplots for PCA
Hi all
I have produced a biplot for a PCA (see attached pdf) that I ran however the
names of the variables which are placed at the end of the arrows overlap and
are thus unreadable. Similarly some of the numbered points overlap. I was
wondering if there was a way to edit the biplot to move the label names and
if not what the best alternative is.
Thanks
Anna
pca<-biodata[,3:10]
2008 Jan 18
2
plotting other axes for PCA
Hi R-community,
I am doing a PCA and I need plots for different combinations of axes (e.g.,
PC1 vs PC3, and PC2 vs PC3) with the arrows indicating the loadings of each
variables. What I need is exactly what I get using biplot (pca.object) but
for other axes.
I have plotted PC2 and 3 using the scores of the cases, but I don't get the
arrows proportional to the loadings of each variables on
2009 Feb 12
1
Different labels for subsets of points in a PCA or RDA biplot
I've tried a few things both with prcomp(), and rda() and its friends
in vegan (including biplot.rda and ordiplot), but can't find a
solution. I'd like to associate subsets of the points in a resulting
biplot ("sites" in the rda object) with different plotting colors/text
styles to emphasize certain sets of points. I can't figure out how to
keep the arrows (for
2002 Sep 09
1
Re: Biplot function of PCA
[was sent a wrong R-help address; manually resent by MM]
Hello
I'am using the 'biplot' and 'biplot.pincomp' functions of the 'mva'
package for my studies.
The biplot represents both the observations and the variables of a
matrix of multivariate data on the same plot.
The observations are represented by their numbers (the line of the data
matrix), but I would need to
2012 Apr 25
1
pca biplot.princomp has a bug?
x=rmvnorm(2000, rep(0, 6), diag(c(5, rep(1,5))))
x=scale(x, center=T, scale=F)
pc <- princomp(x)
biplot(pc)
There are a bunch of red arrows plotted, what do they mean? I knew that the
first arrow labelled with "Var1" should be pointing the most varying
direction of the data-set (if we think them as 2000 data points, each being
a vector of size 6). I also read from
2004 Oct 11
2
hclust title and paste - messed up
I use the following code to scan a (limited) parameter space of clustering
strategies ...
data <- read.table(...
dataTranspose <- t(data)
distMeth <- c("euclidean",
"maximum",
"manhattan",
"canberra",
"binary"
)
clustMeth <- c("ward",
2010 Jan 25
1
PCA: Showing file datalabels on biplot
The script below successfully produces a biplot of the data but the 'site
names' (rows) and the names of the 'response variables' (columns) are shown
as simple numerals (rather than the column and row names). How might I
'enforce' the use of the row/column names used in the datafile (section of
datafile shown below)?
Can anyone help, please?
Section of datafile
sample a b
2009 Apr 28
1
colored PCA biplot
Hi-
I'm trying to make my PCA (princomp) colored. In my csv excel sheet, I have
the first column numbered according to the groupings I want to assign to the
PCA. I've played around with trying to set this first column as the color
vector, but haven't had any luck.
Any suggestions? Thanks,
Hillary
[[alternative HTML version deleted]]
2012 May 07
3
How to plot PCA output?
I have a decent sized matrix (36 x 11,000) that I have preformed a PCA on
with prcomp(), but due to the large number of variables I can't plot the
result with biplot(). How else can I plot the PCA output?
I tried posting this before, but got no responses so I'm trying again.
Surely this is a common problem, but I can't find a solution with google?
The University of Dundee is a
2011 Aug 09
2
reflecting a PCA biplot
Hi Listers,
I am trying to reflect a PCA biplot in the x-axis (i.e. PC1) but am not
having much success. In theory I believe all I need to do is multiply the
site and species scores for the PC1 by -1, which would effectively flip the
biplot.
I am creating a blank plot using the plot command and accessing the results
from a call to rda. I then use the calls to scores to obtain separate site
and
2008 Sep 15
1
how to plot PC2 vs PC 3 in PCA
Hi everybody,
I am doing principal component analysis (PCA) using "prcomp' function. When i did "Biplot", i did not found interesting result and it is based on Principal component (PC) 1 vs PC2. Now, i want to see"Biplot" in combination of either PC1 vs PC3 or PC2 vs PC 3. I did not get the ideas.
Does any one have ideas ?
I am optimistic on getting some idea.