search for: sammons

Displaying 20 results from an estimated 59 matches for "sammons".

2005 Apr 20
4
results from sammon()
Dear all, I'm trying to get a two dimensional embedding of some data using different meythods, among which princomp(), cmds(), sammon() and isoMDS(). I have a problem with sammon() because the coordinates I get are all equal to NA. What does it mean? Why the method fails in finding the coordinates? Can I do anything to get some meaningful results? Thank you very much Domenico
2001 Nov 01
1
Erratic behaviour of sammon()
I'm not sure this list is the right place for this thing. I noticed some erratic behaviour in sammon(). Running sammon on two nearly identical sets of data results in very different results. Below is an example. I create an initial configuration with cmdscale() and store it into 'vec1'. I write this to file, and read it back in again to 'vec2'. According to cor() on the three
2004 Apr 16
2
Masked help page
Hi list, not really a problem to solve but a strange unwanted behavior (at least I do not like it): I'm loading library(multiv) to use sammon. Later I load library(MASS) which tells me that sammon is masked now, because there is also a MASS version of sammon. Since I believe that the MASS version is at least as good as the multiv version, I would also use the MASS version, but help(sammon)
2004 Jun 14
1
error running sammon
Hello, I am inputing a 17 x 17 symetric matrix to sammon. The matrix is a co-occurance matrix with no missing data. If this is at all relevant, running hclust on this matrix works. > samx <- sammon(q23axproduct) I receive the following error: Error in sammon(q23axproduct) : initial configuration must be complete In addition: Warning messages: 1: some of the first 2 eigenvalues are
2005 Apr 20
0
I: results from sammon()
Thanks for the attention paid to my rpoblem. Please find enclosed the matrix with my dissimilarities. This is the only case in which sammon(), from the MASS package, gives me this kind of problems. Domenico > > > -----Messaggio originale----- > > Da: Jari Oksanen [mailto:jarioksa at sun3.oulu.fi] > > Inviato: mercoled?? 20 aprile 2005 11.53 > > A: Domenico Cozzetto >
2002 Jul 30
3
Error running sammon() in multiv package
When I try to run the "sammon" function of the multiv package, I always get this error message: Error in as.vector(dist(a)) : couldn't find function "dist" It happens even with example(sammon). I am running R 1.5.0 on Win98 and I have still installed R 1.4.1 but it doesn't work on the old R version with the older multiv package either. Is there a problem with the
2006 Jan 30
1
Varying results of sammon(), for the same data set
Hello, I have a data set on which I run the sammon algorithm as follows: library(MASS) data = read.table('problemforr.dat') y = cmdscale(data, add=TRUE) s = sammon(data, y$points) (In case it should be relevant, I make the data available at http://idi.ntnu.no/~edsberg/problemforr.dat) With R 2.2.1 on Debian Sid I always get one of two solutions (stress 1.74288 after 10 iterations or
2001 Oct 12
1
MASS: isoMDS and sammon
If tbl is an object of class 'dist', you can do this: a <- sammon(tbl, k=3) But you can't do this: b <- isoMDS(tbl, k=3) Wouldn't it be sensible to have identical interfaces to sammon() and isoMDS() ? I think all that would be needed is to change this: isoMDS <- function(d, y=cmdscale(d, 2), maxit=50, trace=TRUE) { ...into this: isoMDS <-
2008 May 31
0
Advice for working with Sammon's Projection on image data
Hello all, I'm working on a project that uses a SOM to generate feature maps from image data. Each image is a 100x75 pixels and RGBA, so 30,000 elements per image. I wanted to observe the structure of the pixel by pixel euclidean distance (where each image is a point in 30,000 dimensional space) of my image data. Sammon's projection seems appropriate for this, though I'm a bit
2010 May 28
0
error in sammon (duplicates in configuration)
Dear members of R-mailing list, I am using Sammon's Non-Linear Mapping in R as implemented in MASS package. I have two distance matrices (attached with the mail). For the first (/5HT_MACCS_dist.dat/) /sammon()/ works fine but for the second (/5HT_TGT_dist.dat/), I get an error message "configuration has duplicates". I checked both the matrices for duplicate values using/
2006 Jul 19
2
voronoi tessellations
...t; > At 11:46 PM -0400 7/18/06, zubin wrote: > > >Hello, looking to draw a voronoi tessellations in R - can anyone > > >recommend a package that has tackled this? > > > > > >some background: > > > > > >i have a economic data set and created a sammons projection, like to now > > >overlay a voronoi tessellation over the sammons 2-D solution for a slick > > >visual, and potentially color each tessellation element based on a metric. > > > > > >home.u <- unique(home1) > > >home.dist <- dist(home.u)...
2003 Oct 07
0
NaN values returned by cmdscale
Hello all, I'm using R1.7.1 on Linux, generating sammon-optimized MDS plots from distance matrices. This is a calculation I run routinely, often on sample sets of up to 100 samples. This time, with three samples, the sammon function returned an error (shown below), which I tracked down to the cmdscale function it uses to find a starting configuration. In short, cmdscale is returning NaN
2004 Feb 26
2
Multidimensional scaling and distance matrices
Dear All, I am in the somewhat unfortunate position of having to reproduce the results previously obtained from (non-metric?) MDS on a "kinship" matrix using Statistica. A kinship matrix measures affinity between groups, and has its maximum values on the diagonal. Apparently, starting with a nxn kinship matrix, all it was needed to do was to feed it to Statistica flagging that the
2000 Mar 10
1
Problem while installing packages
Dear R team / R helpers / R users , I downloaded R-1.0.0 to install it but I am currently facing the following problem : Installation of packages. Here is the output I had while trying to install RmSQL : ------------- > R INSTALL -l /software/R-1.0.0/library/ /software/archive/R/RmSQL_0.2-1.tar.gz Installing package `RmSQL' ... libs RmSQL.c:7: msql.h: No such file or directory make:
2008 Mar 19
1
one/multi-dimensional scaling with incomplete dissimilarity matrix
Dear David, you asked this question a while ago on the R mailing list and got no answer. I have the same problem and was wondering if you had found a solution Cheers Loic Loic Thibaut, PhD candidate, ARC Centre of Excellence for Coral Reef Studies, School of Marine Biology, James Cook University, Townsville, Qld, 4811, Australia. Tel + 61 747 815 735, Fax: + 61 747 251 570, email:
2005 Jun 28
2
enhanced MDS
Hi again Sorry, in looking again at sammon and isoMDS I see that they seem to do exactly what I want, except that they are non-metric, which means, as I understand it, that they relate the rank orders of the variables rather than the actual distances. Could I use these non-metric MDS packages even if my distances are metric? Thanks Karen -- Karen Kotschy Centre for Water in the Environment
1998 Sep 18
1
R-beta: undefined reference to `realpr_' ?
Hi, Win95 version, trying to build multiv. Following error (no mention in faq etc, but someone may have mentioned it recently). Appreciate any help. ------- Building multiv.dll from multiv.a -------- echo LIBRARY multiv > multiv.def echo EXPORTS >> multiv.def nm multiv.a | sed -n "/^........ [DT] _/s/^........ [BCDRT] _/ /p" >> multiv.def gcc -mdll
2010 Jan 06
1
math function - MDS method
Hi, I need math function which is used in: isoMDS, Sammon and metaMDS method. Anybody know where I may find it? Any manual or webside? I would be very happy Thanks a lot ! -- View this message in context: http://n4.nabble.com/math-function-MDS-method-tp1008294p1008294.html Sent from the R help mailing list archive at Nabble.com.
2007 May 24
4
Converting mbox to Maildir, all prior read messages are downloaded as new
I am running dovecot 0.99. Everything works great; however, now I am looking at several different tools to convert mbox to Maildir. It seems the tools, mb2md.pl, perfect_maildir.pl, and others all do what they claim; however, when the messages are converted and they are stored in Maildir/cur, the email clients download these messages as new. This typically wouldn't be a problem;
2002 Jul 15
1
ReInstalling packages
Hello, I just have upgraded from Mandrake 8.1 to 8.2 and installed R 1.5.1. I now try to reinstall all the packages but get the following error (for the multiv package for instance) : /usr/bin/ld: cannot find -lreadline collect2: ld returned 1 exit status make: *** [multiv.so] Erreur 1 ERROR: compilation failed for package 'multiv' The readline library is under /lib on my system and I