Displaying 20 results from an estimated 500 matches similar to: "All possible combinations of functions within a function"
2016 Apr 21
2
"cophenetic" function for objects of class "dendrogram"
Hello,
I have been using the "cophenetic" function for objects of class "dendrogram" and I have realised that it gives different results when it is used with objects of class "hclust". For instance, running the first example in the help file of the "cophenetic" function,
d1 <- dist(USArrests)
hc <- hclust(d1, "ave")
d2 <-
2016 Apr 21
1
"cophenetic" function for objects of class "dendrogram"
Note that cophenetic.default (which works on the output of hclust(dist(X)))
uses the
row names of X as labels. as.dendrogram.hclust does not retain those row
names
so cophenetic.dendrogram cannot use them (so it orders them based on the
topology of the dendrogram).
Bill Dunlap
TIBCO Software
wdunlap tibco.com
On Thu, Apr 21, 2016 at 7:59 AM, William Dunlap <wdunlap at tibco.com> wrote:
2006 May 09
1
problem accessing trees after read.nexus from ape package
Hello,
I've been trying to figure out how to access the individual elements
from an object of class phylo.
I am reading in 201 trees created by paup as below.
> read.nexus("A_30knj_200t.txt", tree.names= NULL) -> anj30
> anj30[1]
$tree1
$edge
[,1] [,2]
[1,] "-1" "-2"
[2,] "-2" "-3"
[3,] "-3" "1"
2001 Jun 12
1
cophenetic matrix
Hello,
I analyse some free-sorting data so I use hierarchical
clustering.
I want to compare my proximity matrix with the tree
representation to evalute the fitting. (stress, cophenetic correlation
(pearson's correlation)...)
"The cophenetic similarity of two objects a and b is defined as the
similarity level at wich objects a and b become members of the same
cluster during the course of
2007 Feb 17
1
help with cluster stopping rules
Is there a function available in R that implements Mojena's Upper Tail Rule or that draws a Mojena plot?
I would also like to find a function that implements Duda and Hart's stopping rule.
Finally with function cophenet how can I achieve a straightforward Cophenet correlation coefficient (i.e. one number for example 0.876) that gives the agreement between the structure of the
2011 Sep 15
2
Problem looping a function to create/add to new dataframe
Dear List Members,
I have created a function to run a simulation based on a given set of
values within a vector, such that I run the function like this:
new.data<-sapply(vector, function)
In which I run 'function' on every value within a vector that I created.
The result is a matrix of 1000 rows, and as many columns as the length
of the vector.
I modified the function to utilize
2013 Feb 07
1
Feature selection for kmeans
I know that within sum of squares, DB, sillhouette and cophenetic are
indicators of clustering quality, but what indicators I need to observe when
I choose attributes for kmeans?
--
View this message in context: http://r.789695.n4.nabble.com/Feature-selection-for-kmeans-tp4657830.html
Sent from the R help mailing list archive at Nabble.com.
2016 Apr 21
0
"cophenetic" function for objects of class "dendrogram"
I think the results differ only in the order of the labels. The following
function
puts the labels in a standard order and then the results are the same:
canonicalize.dist <- function (distObject)
{
o <- order(labels(distObject))
as.matrix(distObject)[o, o, drop = FALSE]
}
identical(canonicalize.dist(d2), canonicalize.dist(d3))
[1] TRUE
Bill Dunlap
TIBCO Software
2010 Feb 21
1
How to: Compare Two dendrograms (Hierarchical Clusterings) ?
Hello all,
I wish to compare two dendrograms (representing Hierarchical Clusterings).
My problems are several:
1) how do I manually create a dendrogram object ?
That is, how can I reconstruct it as an "hclust" object that creates such a
dendrogram, when all I have is the dendrogram image (but don't have the
underlaying distance matrix that produced it) ?
I see that there is a
2009 Jul 30
1
stepwise variable selection method wanted
Hi List,
I am looking for a variable selection procedure with a forward-backward selection method.
Firstly, it is meant to work with the cophenetic
correlation coefficient (CPCC) and intended to find the variable combination with the
highest cophenetic correlation. Secondly, it is aimed at Gower metric with
wards method (though this could be easily extended) aimed at categorical data.
What I
2009 Nov 03
2
Re place only first NA in column
Dear All,
I am trying to fill in a blank vector ("a") with one value at a time, with
the value of the number of rows in a randomized dataset with rowSums=0.
Below is the code I've got so far, but what I want to be as the last line is
" a[1st NA,]=nz"
such that this will run until all of my NAs are replaced with an integer
value based on randomizations.
2007 May 22
1
Goodness of fit for hclust?
I'd like to get a measure of goodness of fit for a heirarchical
clustering result from hclust. Something that would indicate the
extent to which the dendrogram accurately represents the original
dissimilarity matrix. Is there an easy way to do this?
Or, does anyone have code for computing distances between nodes given
an hclust structure? So far, my searches have come up dry.
-- David
2013 Feb 08
1
vegdist Error en double(N * (N - 1)/2) : tama?o del vector especificado es muy grande
---------- Forwarded message ----------
From: <r-help-owner@r-project.org>
Date: 2013/2/8
Subject: vegdist Error en double(N * (N - 1)/2) : tama?o del vector
especificado es muy grande
To: caro.bello58@gmail.com
Message rejected by filter rule match
---------- Mensaje reenviado ----------
From: caro bello <caro.bello58@gmail.com>
To: r-help@r-project.org
Cc:
Date: Fri, 8 Feb 2013
2011 Sep 09
2
NMDS plot and Adonis (PerMANOVA) of community composition with presence absence and relative intensity
Hi!
Thanks for providing great help in R-related statistics. Now, however I'm
stuck. I'm not a statistics person but I was recommended to use R to perform
a nmds plot and PerMANOVA of my dataset.
Sample(treatment) in the columns and species (OTU) in the rows. I have 4
treatments (Ambient Temperature, Ambient temperature+Low pH, High
temperature, High temperature+low pH), and I have 16
2010 Mar 16
1
memory failure in adonis function (permanova)
Dear all,
I am trying to get a PERMANOVA with quite large data set. I am reading a lot
about this question, but I do not get the answer about it. Although I know
that the R function is adonis () (vegan package), it does not work:
adonis(Pha.env~SPha, data=Pha, permutations=10)
The error message:
Error: cannot allocate vector of size 334.2 Mb
In addition: Warning messages:
1: In vegdist(lhs,
2010 Feb 02
2
hvcluster() with distance method from vegdist(), package = vegan
hello,
i'd be happy if someone could provide help with the following problem:
i have a dist.matrix that comes from vegdist() function of the vegan
package. the used method = "horn" is not accepted as argument in
hvcluster(...,dist.method="...").
is there a way to incorporate the method "horn" in hvcluster()?
thanks in advance!
yours,
kay
--
View this
2011 Oct 03
4
distance coefficient for amatrix with ngative valus
Hi,
I need to run a PCoA (PCO) for a data set wich has both positive and negative values for variables. I could not find any distancecoefficient other than euclidean distace running for the data set. Are there any other coefficient works with negtive values.Also I cannot get summary out put (the eigen values) for PCO as for PCA.
Thanks.
Dilshan
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2006 Nov 17
3
gower distance calculation
Hello
I have 2 rows in a matrix and I want to calculate the Gower Distance between
the 2 , how can I do it?
I searched and found nothing that can help me, and my program doesn't know
the gdist function and I couldn't find it on the R help site.
Can anyone help me plz
Thank u all
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2011 Sep 13
2
help with hclust
Hello,
how can I get the similarity value (i.e., the inner cluster similarity) that was used to cut a hierarchical tree at a specific height?
I would appreciate your help!
Best regards,
Madeleine
2011 May 17
1
simprof test using jaccard distance
Dear All,
I would like to use the simprof function (clustsig package) but the available distances do not include Jaccard distance, which is the most appropriate for pres/abs community data. Here is the core of the function:
> simprof
function (data, num.expected = 1000, num.simulated = 999, method.cluster = "average",
method.distance = "euclidean", method.transform =