R help - Aug 2011 - Help with calc_sde

I cannot seem to get this to work? I have weighted data points that I want to
fit an sd-ellipse to, but the ellipse is not right? I have attached a .tiff of
what I get.
I'm wondering if it's not looking at my actual data, but taking the data
from the example? I ask this because I don't know where "Title"
comes from in the graph?
Also, I want to put calcentre=FALSE, but if I do this I get the following error:
                 Error in data.frame(..., check.names = FALSE) :
                 arguments imply differing number of rows: 10, 0
I want the weighted mean centre of the ellipse, not the mean centre.
Can you tell me what is going on and why it isn't calculating the proper
ellipse? I'm going to start crying soon.

Sabeena

library(xlsReadWrite)
Low <- read.xls('LowEB.xls')
attach(Low)
Lwts <- read.xls('LowWtsEB.xls')
attach(Lwts)
cE.add <- c(0.16,1.00,0.42,0.17,0.11,0.49,0.28,0.20,0.45,0.23)
library(aspace)

x11()
plot(x =Low[,1], y = Low[,2], type = 'p', pch = 16, col =
'darkgoldenrod1', cex = 2*cE.add,xlim=c(2,10),ylim=c(40,105))

calc_sde(id=4, filename="EBLOW_Output.txt", centre.xy=NULL,
calccentre=TRUE,
weighted=TRUE, weights=Lwts, points=Low, verbose=TRUE)

plot_sde(plotnew=FALSE, plotSDEaxes=FALSE,
plotcentre=FALSE,plotweightedpts=FALSE,plotpoints=FALSE,sde.col='darkgoldenrod1',sde.lwd=2)





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