Displaying 20 results from an estimated 40000 matches similar to: "Help Graph edit distance in R"
2009 Feb 13
0
Graph Edit Distance
Dear R Users
I'm trying to acquire a metric for how similar two graphs are by doing
inexact graph matching. I heard that the "Graph Edit Distance" is one
such metric. Do you know of any R packages (off the top of your head)
that implement an algorithm for calculating this from a pair of
adjacency matrices? I had a quick skim-look on Cran but couldn't find
anything.
Cheers
Tom
2010 May 25
1
Hierarchical clustering using own distance matrices
Hey Everyone!
I wanted to carry out Hierarchical clustering using distance matrices i have
calculated ( instead of euclidean distance etc.)
I understand as.dist is the function for this, but the distances in the
dendrogram i got by using the following script(1) were not the distances
defined in my distance matrices.
script:
var<-read.table("the distance matrix i calculated",
2004 Jan 30
1
How to create own distance measure in cluster ?
Hi everyone,
I want to create my own distance measure, other than 'euclidean' or
'manhatan', to use in cluster pckgs. To do this I think that I need to
change dist(), in mva pckg, or daisy(), in cluster pckg. (or is there a
cleaver way ?)
But this functions are in fact things like: .Fortran( "daisy", ... ) or
.C("dist",...).
I tried unsuccessfully to find
2009 Mar 02
0
Distance between clusters
Dear friends
I reformulate the question. I think I did not formulate it properly.
I have some data on some sites. I can define a dissimilarity between each pair
of sites. Using this dissimilarity, I have clustered the sites using the
hclust algorithm, with method ward. I then obtain 48 clusters, by cutting the
tree using cutree with k=48.
I would now like to estimate the distance between
2009 Mar 02
0
Distance between clusters
Dear friends
I reformulate the question. I think I did not formulate it properly.
I have some data on some sites. I can define a dissimilarity between each pair
of sites. Using this dissimilarity, I have clustered the sites using the
hclust algorithm, with method ward. I then obtain 48 clusters, by cutting the
tree using cutree with k=48.
I would now like to estimate the distance between
2012 Sep 17
1
self defined distance matrix in NbClust
i m using a package NbClust for cluster analysis. in the following algorithm
->NbClust(m, diss="NULL", distance = "euclidean", min.nc=2, max.nc=15, method = "ward", index = "all", alphaBeale = 0.1)
i want to define my own dissimilarity matrix of dimension 38*38. my original data "m" is a matrix of 365*38. whenever i define my own dissimilarity
2008 Sep 02
2
cluster a distance(analogue)-object using agnes(cluster)
I try to perform a clustering using an existing dissimilarity matrix that I
calculated using distance (analogue)
I tried two different things. One of them worked and one not and I don`t
understand why.
Here the code:
not working example
library(cluster)
library(analogue)
iris2<-as.data.frame(iris)
str(iris2)
'data.frame': 150 obs. of 5 variables:
$ Sepal.Length: num 5.1 4.9 4.7
2001 May 30
3
Transformation of dissimilarity or distance matrix
Dear List,
is there an elegant (or even not elegant) way how to transform
dissimilarity or distance matrix A
(or, in general, arbitrary symmetrical matrix) by transposition of rows and
columns into a form
closest to "block diagonal" matrix B?
The matrix A is adjusted the following way
A[A<epsilon] <-0 #(epsilon is given "small" number)
B: (in its ideal form)
2009 Dec 01
2
Distance between sets of points in transformed environmental space
Dear friends,
I have several sets of points in a transformed environmental space. Each set
of points can be represented as a cloud in the environmental space.
This space is spanned by n coordinates, corresponding to the first n PCs of 36
PCs of some environmental variables (12 monthly minimum temperatures, 12
monthly maximum temperature, 12 monthly precipitations).
I would like to calculate
2010 Feb 11
0
cluster/distance large matrix (fwd)
On Thu, 11 Feb 2010, Christian Hennig wrote:
>It is well know that hierarchical methods are problematic with too large
>dissimilarity matrices; even if you resolve the memory problem, the number of
>operations required is enormous.
There is at least one exception to this. Single-linkage hierarchical clustering with a convex distance such as Euclidean distance is feasible for quite
2008 Oct 13
1
Gower distance between a individual and a population
Hi the list,
I need to compute Gower distance between a specific individual and all
the other individual.
The function DAISY from package cluster compute all the pairwise
dissimilarities of a population. If the population is N individuals,
that is arround N^2 distances to compute.
I need to compute the distance between a specific individual and all
the other individual, that is only N
2010 Apr 23
0
A distance measure between top-k list
Hi folks,
Here is the problem. I am giving an example .I want to find a measure
of similarity or dissimilarity among ranking (of students of a same class
of size say 50)by two judges. But instead of observing the rank of all the
50 students
(Where we could have used rank correlation measures)in each case what I have
is
2 list of top 20 students chosen by each judge.
The following paper gives out
2011 Jul 08
1
Visualizing a dissimilarity matrix in Euclidean space
Hi,
I have a set of nodes and a dissimilarity matrix for them, as well as a csv
file in which the diss matrix has been converted to [node_1, node_2,
dissimilarity] format. I would like to visualize this as a graph in
Euclidean space (that is, similar nodes clumped together in clusters),
rather than the seriation visualization given by dissplot(). I am using
Network WorkBench for my
2010 Nov 16
1
Bug in agrep computing edit distance?
The documentation for agrep says it uses the Levenshtein edit distance,
but it seems to get this wrong in certain cases when there is a
combination of deletions and substitutions. For example:
> agrep("abcd", "abcxyz", max.distance=1)
[1] 1
That should've been a no-match. The edit distance between those strings
is 3 (1 substitution, 2 deletions), but agrep matches
2010 Feb 11
1
cluster/distance large matrix
Hi all,
I've stumbled upon some memory limitations for the analysis that I want to
run.
I've a matrix of distances between 38000 objects. These distances were
calculated outside of R.
I want to cluster these objects.
For smaller sets (egn=100) this is how I proceed:
A<-matrix(scan(file, n=100*100),100,100, byrow=TRUE)
ad<-as.dist(A)
2008 Feb 20
1
clustering problem
First I just want to say thanks for all the help I've had from the
list so far..)
I now have what I think is a clustering problem. I have lots of
objects which I have measured a dissimilarity between. Now, this list
only has one entry per pair, so it is not symmetrical.
Example input:
NameA NameB Dist
189_1C2 189_1C1 0
189_1C3 189_1C1 0.017
189_1C3 189_1C2 0.017
189_1C4 189_1C1 0
2010 Sep 21
1
partial dbRDA or CCA with two distance objects in Vegan.
I am trying to use the cca/rda/capscale functions in vegan to analyse
genetic distance data ( provided as a dist object calculated using
dist.genpop in package adegenet) with geographic distance partialled out
( provided as a distance object using dist function in veganthis method
is attempting to follow the method used by Geffen et al 2004 as
suggested by Legendre and . FORTIN (2010).
I
2004 May 28
6
distance in the function kmeans
Hi,
I want to know which distance is using in the function kmeans
and if we can change this distance.
Indeed, in the function pam, we can put a distance matrix in
parameter (by the line "pam<-pam(dist(matrixdata),k=7)" ) but
we can't do it in the function kmeans, we have to put the
matrix of data directly ...
Thanks in advance,
Nicolas BOUGET
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
2010 Nov 17
2
Bug in agrep computing edit distance?
I posted this yesterday to r-help and Ben Bolker suggested reposting it
here...
Dickison, Daniel <ddickison <at> carnegielearning.com> writes:
>
> The documentation for agrep says it uses the Levenshtein edit distance,
> but it seems to get this wrong in certain cases when there is a
> combination of deletions and substitutions. For example:
>
> >