Displaying 20 results from an estimated 600 matches similar to: "ordination in vegan"
2011 Nov 07
2
ordination in vegan: what does downweight() do?
Can anyone point me in the right direction of figuring out what downweight()
is doing?
I am using vegan to perform CCA on diatom assemblage data. I have a lot of
rare species, so I want to reduce the influence of rare species in my CCA. I
have read that some authors reduce rare species by only including species
with an abundance of at least 1% in at least one sample (other authors use
5% as a
2010 Apr 13
1
vegan (ordisurf): R² for smoothed surfaces
Dear r-helpers,
I just read in an article by Virtanen et al. (2006) where vegetation-environment relationships are studied by fitting smoothed surfaces on an NMDS ordination using GAMs (Wood 2000). The authors describe, that they used R? as goodness-of-fit statistic, which they compare to the R? of fitted vectors. Calculations were carried out using the package vegan (Oksanen).
I know that I can
2012 Jul 27
1
labeling loading vectors in vegan
Hello,
I am using vegan to do an NMDS plot and I would like to suppress the labels
for the loading vectors. Is this possible? Alternatively, how can I avoid
overlap?
Many thanks for the help.
Example code:
#perform NMDS using metaMDS() function
spe.nmds<-metaMDS(data, distance='bray',k=2 , engine = "isoMDS",
autotransform=F, trymax=1000)
#calculate the loading (i.e.,
2011 May 10
3
metaMDS and envfit: Help reading output
Hello R experts,
I've used metaMDS to run NMDS on some fish abundance data, and am also working on correlating environmental data to the NMDS coordinates. I'm fairly new to metaMDS and NMDS in general, so I have what are probably some very basic questions. My fish abundance data consists of 66 sites for which up to 20 species of fish were identified and counted. I ran metaMDS on this data
2002 Dec 16
1
unknown decorana error returned (vegan package)
Hi
After trying a simple decorana analysis (from the vegan package) on a simple
data frame which contains no NA's the following error was returned:
> tt_decorana(covN)
Error in decorana(covN) : NA/NaN/Inf in foreign function call (arg 1)
Have any vegan users come across this error and know what can be done about it?
Cheers,
J
2006 Nov 16
2
question about capscale (vegan)
Hello,
I am interested in using the capscale function of vegan package of R. I
already have a dissimilarity matrix and I am intended to use it as
'distance' argument. But then, I don't know what kind of data must be in
'comm' argument. I don't understand what type of data must be referred
as 'species scores' and 'community data frame' since my data refer to
2010 Nov 17
1
Total inertia in package Vegan?
Dear all at the R-project help list.
I have run into a problem when it comes to getting values for "total inertia" and "R-squared" for my DCA using "decorana" in the package "vegan". I have tried the "goodness" function, but the reply indicates that it does not work with "decorana" class objects. In Canoco one gets the Total inertia in
2013 Jul 12
2
vegan capscale 'subscript out of bounds' error
Hi list,
I am using the capscale function in vegan_2.0-7 to do a constrained
principal coordinates analysis, and I kept getting the following error
message:
Error in Y.r[, oo, drop = FALSE] : subscript out of bounds
I googled but I couldn't find an answer. Could anyone tell me why this
error msg and what to do?
Here is the command I used:
2010 Apr 27
1
cca standard error species
Dear all,
I realised a correspondence analysis with function cca() of vegan library.
Just like in Okansen (2010) in the example of R help:
library(vegan)
data(varespec)
data(varechem)
vare.cca<-cca(varespec~ Al + P + K, varechem)
With plot.cca() function I represented the species matrix in the next way:
plot(vare.cca,display="species")
Being similar to:
plot((c(-2,2)),(c(-2,2)),
2008 Sep 26
1
cca constraining variables table
I performed canonical correspondence analysis (cca) with the example data of
vegan, but I'm not able to obtain a table like scores() for the constraining
variables. I can see them in the summary() mode, but it would be great to
have in a separate table. Any suggestion?, thanx Gianandrea
require(vegan)
data(varespec)
data(varechem)
vare.cca<-cca(varespec,varechem)
scores(vare.cca)
2016 Sep 05
3
Tests of all canonical RDA axes
Estimados,
Buenas Tardes,
Estoy teniendo problema para testar la significancia de los ejes del RDA. NO se cual seria el error.
Alguien me podría ayudar? Desde ya muchas gracias.
Saludos, Luis
# Tests of all canonical axes
anova.cca(ssp.rda.hel, by="axis", step=1000)#Para saber la significancia de cada eje
Error in anova.cca(ssp.rda.hel, by = "axis", step = 1000) :
2004 May 13
2
BIO-ENV procedure
I've been unable to find a R package that provides the means of
performing Clarke & Ainsworth's BIO-ENV procedure or something
comparable. Briefly, they describe a method for comparing two separate
sample ordinations, one from species data and the second from
environmental data. The analysis includes selection of the 'best'
subset of environmental variables for explaining
2009 Nov 05
1
plot.envfit/move labels
Dear r-helpers!
Jan Thiele asked r-help-list in february, but I could not find an answer to his question. I have the same problem:
While preparing figures of 'envfit' plots with vegan for publication, I ran into a layout problem, that I found no solution for in the literature or the help archive:
The labels of the vectors that indicate correlations of environental variables sometimes
2012 Nov 27
1
CCA plot
Hi, I have a couple questions about fitting environmental (land use
factors, plant species presence-absence, and soil variables) constraints to
my CCA biplot. 1. After successfully plotting species and site scores in my
CCA, I have been trying to insert the biplot arrows of the environmental
constraints in my data set using the text() function. When I do that, the
plot changes completely. Is there
2012 May 09
1
reception of (Vegan) envfit analysis by manuscript reviewers
I'm getting lots of grief from reviewers about figures generated with
the envfit function in the Vegan package. Has anyone else struggled to
effectively explain this analysis? If so, can you share any helpful
tips?
The most recent comment I've gotten back: "What this shows is which
NMDS axis separates the communities, not the relationship between the
edaphic factor and the
2012 May 10
1
envfit output (vegan package) - not sure what it means
I'm pretty new to R and would appreciate some help interpreting the output of
a function that was recommended to me.
I've used the *envfit *function in the vegan package to plot vectors of four
climate variables onto a species matrix ordination. The output indicates
that only a single variable (mean_temp) is significant:
***VECTORS
NMDS1 NMDS2 r2
2009 Sep 09
2
"predict"-fuction for metaMDS (vegan)
Dear r-Community,
Step1: I would like to calculate a NMDS (package vegan, function metaMDS) with species data.
Step2: Then I want to plot environmental variables over it, using function envfit.
The Problem: One of these environmental variables is cos(EXPOSURE). But for flat releves there is no exposure. The value is missing and I can't call it 0 as 0 stands for east and west. Therefore I
2013 Apr 11
1
Cannot find ldfortran (R on Cygwin)
Hi
I am new to Cygwin and Linux.
I installed R under Cygwin as part of the setup
I chose "All" during installation, for all packages. So I have the FULL
installlation of cygwin up and running, including gfortran.
*Under Cygwin, how do I check and configure the path to the various
libraries?*
I am trying below command and it says, cannot find "lgfortran"
But I have installed
2010 Feb 13
2
NMDS ordination
Hi
Im currently trying to plot my NMDS data together with fitted variables
(envfit funct) on an ordination plot. The plot function shows two
displays="sites" and "sp". I was wondering how to plot it so that the sites
come up as different points for different sites but the species come up as
actual names? It looks a little busy at the moment with everything in.
Sya
--
View
2012 May 23
1
procrustes (vegan) plot of residual differences
Hello
This is a simple question but I couldn't google an answer.
In the procrustes function of the vegan package, one uses
plot(procrustes_object, kind=2) to obtain a plot of the residual
differences. For instance:
data(varespec)
vare.dist <- vegdist(wisconsin(varespec))
library(MASS)
mds.null <- isoMDS(vare.dist, tol=1e-7)
mds.alt <- isoMDS(vare.dist,