Displaying 20 results from an estimated 2000 matches similar to: "Quick question about princomp/biplot"
2006 Jul 31
1
How does biplot.princomp scale its axes?
I'm attempting to modify how biplot draws its red vectors (among other
things). This is how I've started:
Biplot <- function(xx, comps = c(1, 2), cex = c(.6, .4))
{
## Purpose: Makes a biplot with princomp() object to not show arrows
## ----------------------------------------------------------------------
## Arguments: xx is an object made using princomp()
##
2003 Apr 04
2
biplot
Dear list,
I want to perform a biplot, using customized titels for the x and y axis.
Setting xlab="" and ylab="" resulted in an error, e.g.:
> data(USArrests)
> biplot(princomp(USArrests),xlab="",ylab="")
Error in biplot.default(t(t(scores[, choices])/lam), t(t(x$loadings[, :
length of dimnames[1] not equal to array extent
>
How do I
2006 Sep 06
2
biplot label size
Which is the parameter that is used to decrease the size of ylabs
plotted in biplot? I tried playing with cex and cex.lab I am not getting
it right
pc <- princomp(USArrests)
biplot(pc, xlabs = rep("", nrow(USArrests)),ylabs=(colnames(USArrests)))
Thanks../Murli
[[alternative HTML version deleted]]
2004 Sep 30
3
biplot.princomp with loadings only
Hi
is there a way to plot only the loadings in a biplot (with the nice
arrows), and to skip the scores?
thanks
christoph
2012 Jun 18
2
How can I "declutter"/make a biplot less messy in R
I am doing a principle component analysis on a dataset with a lot of
different variables and have constructed a biplot of the data.
Unfortunately, as can be seen on the attached image, the biplot is very
messy, cluttered, and hard to read. I have performed a few modifications
including outlier removal from a few of the variables, which has made the
plot better, however it still is too cluttered
2013 Feb 11
1
Clean up biplot resulting from princomp()
Dear R-helpers,
The vectors in my biplot are completely obscured by the ~1400 labels R is
printing on my biplot. I don't really care about the labels. How can I make
the biplot without the annoying labels?
See attached, if that helps you see my problem.
Many thanks,
Mark Na
2009 Sep 02
4
"biplot" graphical options?
Dear R-help fellows
good afternoon.
I am struggling in the attempt to impose some graphical conditions (changing point symbols, colors, etc) to biplot function (I am using it to visualize the results of princomp) but I can't apparently manage to change anything but the axis... and I have been browsing manuals and vignettes without finding any explicit suggestions on how to operate...
Can
2002 Apr 30
1
ylim in biplot does not seem to work (PR#1498)
Full_Name: Hinrich Göhlmann
Version: 1.4.1
OS: Windows 2000
Submission from: (NULL) (148.177.130.121)
Hi all,
I've searched the known bugs and hopefully I did not oversee this one...
When I have done a normal
zz<-princomp(na.omit(raw.data))
and I then draw a biplot with
biplot(zz,cex=c(.1,.7),col=c(5,1),choice=c(1,2),xlim=c(-2,2),ylim=c(-5,2))
the x axis gets set properly, but the y
2005 Sep 16
1
About princomp
Hi,
I run the example for princomp for R211
I got the following error for biplot
> ## The variances of the variables in the
> ## USArrests data vary by orders of magnitude, so scaling is appropriate
> (pc.cr <http://pc.cr> <- princomp(USArrests)) # inappropriate
Erreur dans cov.wt(z) : 'x' must contain finite values only
> princomp(USArrests, cor = TRUE) # =^=
2009 Feb 24
1
biplot.princomp - changing score labels
Dear R helpers,
When producing a PCA biplot, vectors of environmental variables (as red
arrows with labels) and scores of the observations (black labels
(observation names)) are plotted by default. How can I change the
graphical output? Let's say I would like that the scores are plottet
only as symbols and not text. The only solution I found was this post in
the help archive
2010 Apr 27
1
Symbols in biplot
Hello all,
I just started in on R today. I am at the point where I am trying
to distinguish different groups of data (hydrochemical data) in
biplot. I search and found a post about converting the sample number
in biplot to a symbol like x or +
"> temp <- matrix(runif(50), nrow=10)
> temp.pca <- princomp(temp)
> biplot(temp.pca, xlabs=c("A", "A",
2005 Apr 21
1
biplot graphical problems
Hello,
I have a graphical problem concerning a biplot that I was ask to insert
in a scientific work to be published.
I've performed a princomp analysis and produce the relative biplot but
the labels of variables are out of margin (see attached file).
When I try to wide the x axis by the function xlim=c(i:j), nothing
happens if not a partial shift of the x range. Is there any specific
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
1999 Sep 09
1
princomp
Peter,
As I understand your Q. You probably have data that is similar to each other
like stock Prices for all RHS variable. In that case the difference between corr
and cov is not significant; however, if your RHS contains totally dissimilar
variables it matters a great deal. If x1 income, x2 job type, x3 Education
level, etc..., then taking cov of these variables would not be desireable
2009 Mar 01
3
Modifying a built-in R function
Hello,
Something incredible (at least for me) has happen. Yesterday night I
downloaded biplot.R to edit this function and add new features I wished.
Namely I wanted to plot points belonging to different groups using different
colors and symbols. I identified which part of the original code I had to
modify. Then, I rename biplot by biplotes and executing biplotes(x), being x
a princomp class
2006 Dec 18
1
Replacing labels with symbols in biplot
Dear all
I would like to replace labels for x in biplot() with symbols (points)
that will visually illustrate different classes/groups. After an
unsuccessful search through the documents and archives, I turn to the
list for help - any suggestions that can point me in the right
direction?
Thanks
Mat Vanderklift
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
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
2010 May 31
0
Documentation of biplot for princomp
Hi,
I think that the documentation for the biplot function `biplot.princomp' is
inconsistent with what it actually does. Here is what the documentation
states:
pc.biplot
If true, use what Gabriel (1971) refers to as a "principal component
biplot", with lambda = 1 and observations scaled up by sqrt(n) and variables
scaled down by sqrt(n). Then inner products between
2010 Jun 30
3
Factor Loadings in Vegan's PCA
Hi all,
I am using the vegan package to run a prcincipal components analysis
on forest structural variables (tree density, basal area, average
height, regeneration density) in R.
However, I could not find out how to extract factor loadings
(correlations of each variable with each pca axis), as is straightforwar
in princomp.
Do anyone know how to do that?
Moreover, do anyone knows