Re: [R] Problem with data frame when using xYplot?
Problem solved! I was so focused on reproducing the plotmeans() functionality with xYplot() that I completely overlooked the fact that my data does not allow a x-y plot, as only Sodium is a numeric variable while Position and AltGeo are factors! Using unclass() to make Position a numeric variable does the trick: tmp$Position - unclass(tmp$Position) The code below does the trick. Now I only need to figure out how to tweak the x axis to pretend I am plotting a factor, i.e. plotting labels Inside and Outside. Cheers, Sander. library(Hmisc) library(Lattice) tmp - structure(list(Position = structure(as.integer(c(1, 2, 1, 2, 1, 2, 1, 2)), .Label = c(Inside, Outside), class = factor), AltGeo = structure(as.integer(c(1, 1, 2, 2, 3, 3, 4, 4)), .Label = c(Basalt-High, Basalt-Low, Quartz-High, Quartz-Low), class = factor), Sodium = c(27.3, 26.9, 25, 18.1, 4.67, 5.56, 10.7, 5.67 ), SD = c(5.3851648071345, 2.42097317438899, 20.1618451536560, 15.2679766541317, 5.45435605731786, 8.09492296305393, 10.6183802907976, 8.06225774829855), Nobs = c(9, 9, 9, 9, 9, 9, 9, 9), Lower = c(25.5382783976218, 26.0818978307592, 18.2793849487813, 13.0217855597339, 2.84854798089405, 2.85724790120425, 7.12720656973412, 2.97924741723382), Upper = c(29.1283882690448, 27.6958799470186, 31.7206150512187, 23.2004366624884, 6.48478535243929, 8.25386320990686, 14.2061267635992, 8.35408591609952)), .Names = c(Position, AltGeo, Sodium, SD, Nobs, Lower, Upper), row.names = c(1, 2, 3, 4, 5, 6, 7, 8), class = data.frame) tmp$Position - unclass(tmp$Position) xYplot(Cbind(Sodium,Lower,Upper) ~ Position|AltGeo, groups=AltGeo, data=tmp, ylim=c(min(tmp$Lower)-1,max(tmp$Upper)+1), xlab=Position, ylab=Sodium ) Sander Oom wrote: Dear all, I am trying to plot means and error bars using xYplot, but I get an error message from xYplot which I can not figure out: Error in Summary.factor(..., na.rm = na.rm) : range not meaningful for factors The data frame (tmpNa) was created using aggregate. I have used dump to created the code below, which generates the same error. Can anybody tell me what is wrong with the data frame? Thanks in advance, Sander. library(Hmisc) tmpNa - structure(list(Position = structure(as.integer(c(1, 2, 1, 2, 1, 2, 1, 2)), .Label = c(Inside, Outside), class = factor), AltGeo = structure(as.integer(c(1, 1, 2, 2, 3, 3, 4, 4)), .Label = c(Basalt-High, Basalt-Low, Quartz-High, Quartz-Low), class = factor), Sodium = c(27.3, 26.9, 25, 18.1, 4.67, 5.56, 10.7, 5.67 ), SD = c(5.3851648071345, 2.42097317438899, 20.1618451536560, 15.2679766541317, 5.45435605731786, 8.09492296305393, 10.6183802907976, 8.06225774829855), Nobs = c(9, 9, 9, 9, 9, 9, 9, 9), Lower = c(25.5382783976218, 26.0818978307592, 18.2793849487813, 13.0217855597339, 2.84854798089405, 2.85724790120425, 7.12720656973412, 2.97924741723382), Upper = c(29.1283882690448, 27.6958799470186, 31.7206150512187, 23.2004366624884, 6.48478535243929, 8.25386320990686, 14.2061267635992, 8.35408591609952)), .Names = c(Position, AltGeo, Sodium, SD, Nobs, Lower, Upper), row.names = c(1, 2, 3, 4, 5, 6, 7, 8), class = data.frame) xYplot(Cbind(Sodium,Lower,Upper) ~ AltGeo, groups=Position, data=tmpNa) version _ platform i686-pc-linux-gnu arch i686 os linux-gnu system i686, linux-gnu status major2 minor1.0 year 2005 month04 day 18 language R -- Dr. Sander P. Oom Animal, Plant and Environmental Sciences, University of the Witwatersrand Private Bag 3, Wits 2050, South Africa Tel (work) +27 (0)11 717 64 04 Tel (home) +27 (0)18 297 44 51 Fax +27 (0)18 299 24 64 Email [EMAIL PROTECTED] Web www.oomvanlieshout.net/sander __ R-help@stat.math.ethz.ch mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide! http://www.R-project.org/posting-guide.html
Re: [R] Problem with data frame when using xYplot?
I have edited the code (hacked from another graph) to provide more
control over the different elements of the graph. Now we have a graph at
publication quality! Slowly the power of R graphics is shining through
the thick cloud of options! Beautiful.
library(Hmisc)
library(lattice)
ltheme - canonical.theme(color = FALSE) ## in-built BW theme
ltheme$strip.background$col - transparent ## change strip bg
lattice.options(default.theme = ltheme) ## set as default
tmp -
structure(list(Position = structure(as.integer(c(1, 2, 1, 2,
1, 2, 1, 2)), .Label = c(Inside, Outside), class = factor),
AltGeo = structure(as.integer(c(1, 1, 2, 2, 3, 3, 4, 4)), .Label =
c(Basalt-High,
Basalt-Low, Quartz-High, Quartz-Low), class = factor),
Sodium = c(27.3, 26.9, 25, 18.1,
4.67, 5.56, 10.7, 5.67
), SD = c(5.3851648071345, 2.42097317438899, 20.1618451536560,
15.2679766541317, 5.45435605731786, 8.09492296305393, 10.6183802907976,
8.06225774829855), Nobs = c(9, 9, 9, 9, 9, 9, 9, 9), Lower =
c(25.5382783976218,
26.0818978307592, 18.2793849487813, 13.0217855597339, 2.84854798089405,
2.85724790120425, 7.12720656973412, 2.97924741723382), Upper =
c(29.1283882690448,
27.6958799470186, 31.7206150512187, 23.2004366624884, 6.48478535243929,
8.25386320990686, 14.2061267635992, 8.35408591609952)), .Names =
c(Position,
AltGeo, Sodium, SD, Nobs, Lower, Upper), row.names = c(1,
2, 3, 4, 5, 6, 7, 8), class = data.frame)
tmp$xvar - rep(1:4, each=2)+rep(c(-.05,.05), 4)
tmp
sp - list(superpose.symbol = list(pch = c(16,1), cex = 1))
xYplot(Cbind(Sodium,Lower,Upper) ~ xvar, groups=Position, data=tmp,
scales=list(y='free',x=list(at=1:4, labels=levels(tmp$AltGeo))),
xlim=c(0.5, 4.5), ylim=c(min(tmp$Lower)-1,max(tmp$Upper)+1),
xlab='AltGeo', ylab='Sodium',
panel = function(x, y, type, ...) {
panel.xYplot(x, y, type=p,...)
lpoints(x, y, pch=16, col=white, cex=2)
panel.superpose(x, y, type=p, ...)
},
par.settings = sp,
auto.key=list(columns=1, x=0.7, y=0.8, corner = c(0,0))
)
Sander Oom wrote:
An off list response from Mat Soukop (thanks Mat!!) provides an even
more elegant solution (see code below)! I have included the original
code, so people can decide whether to plot in a single panel or in
multiple panels. Now we have a fully functional workaround to get
plotmeans{gplots} for multiple factors using lattice! Great!
library(Hmisc)
library(lattice)
tmp -
structure(list(Position = structure(as.integer(c(1, 2, 1, 2,
1, 2, 1, 2)), .Label = c(Inside, Outside), class = factor),
AltGeo = structure(as.integer(c(1, 1, 2, 2, 3, 3, 4, 4)), .Label =
c(Basalt-High,
Basalt-Low, Quartz-High, Quartz-Low), class = factor),
Sodium = c(27.3, 26.9, 25, 18.1,
4.67, 5.56, 10.7, 5.67
), SD = c(5.3851648071345, 2.42097317438899, 20.1618451536560,
15.2679766541317, 5.45435605731786, 8.09492296305393, 10.6183802907976,
8.06225774829855), Nobs = c(9, 9, 9, 9, 9, 9, 9, 9), Lower =
c(25.5382783976218,
26.0818978307592, 18.2793849487813, 13.0217855597339, 2.84854798089405,
2.85724790120425, 7.12720656973412, 2.97924741723382), Upper =
c(29.1283882690448,
27.6958799470186, 31.7206150512187, 23.2004366624884, 6.48478535243929,
8.25386320990686, 14.2061267635992, 8.35408591609952)), .Names =
c(Position,
AltGeo, Sodium, SD, Nobs, Lower, Upper), row.names = c(1,
2, 3, 4, 5, 6, 7, 8), class = data.frame)
tmp$PosNum - unclass(tmp$Position)
tmp
(labs - unique(tmp$Position))
# plot factor levels in seperate panels
xYplot(Cbind(Sodium,Lower,Upper) ~ PosNum|AltGeo, data=tmp, nx=FALSE,
xlim=c(0.5,2.5),
ylim=c(min(tmp$Lower)-1,max(tmp$Upper)+1),
scales = list(x = list(at=seq(1, 2, by=1), labels = labs)),
xlab=Position, ylab=Sodium
)
new.back - trellis.par.get(background)
new.back$col - white
newcol - trellis.par.get(superpose.symbol)
newcol$col - c('green4','blue','red','black')
newcol$pch - c(16,1,4,8)
new.line - trellis.par.get(box.rectangle)
new.line$col - 'black'
trellis.par.set(background, new.back)
trellis.par.set(superpose.symbol, newcol)
trellis.par.set(box.rectangle, new.line)
# Plot factor levels in one graph
tmp$xvar - rep(1:4, each=2)+rep(c(-.05,.05), 4)
xYplot(Cbind(Sodium,Lower,Upper) ~ xvar, groups=Position, data=tmp,
scales=list(y='free',x=list(at=1:4,
labels=levels(tmp$AltGeo))),
xlab='AltGeo', xlim=c(.5, 4.5),
key=list(points=Rows(trellis.par.get(superpose.symbol),1:2),
text=list(lab =as.character(levels(tmp$Position)),
col=trellis.par.get(superpose.symbol)$col[1:2]),
columns=2, cex=1, title=Position,
cex.title=1.1))
Sander Oom wrote:
Problem solved!
I was so focused on reproducing the
Re: [R] Problem with data frame when using xYplot?
On Friday 13 May 2005 08:07 am, Sander Oom wrote:
An off list response from Mat Soukop (thanks Mat!!) provides an even
more elegant solution (see code below)! I have included the original
code, so people can decide whether to plot in a single panel or in
multiple panels. Now we have a fully functional workaround to get
plotmeans{gplots} for multiple factors using lattice! Great!
library(Hmisc)
library(lattice)
tmp -
structure(list(Position = structure(as.integer(c(1, 2, 1, 2,
1, 2, 1, 2)), .Label = c(Inside, Outside), class = factor),
AltGeo = structure(as.integer(c(1, 1, 2, 2, 3, 3, 4, 4)), .Label =
c(Basalt-High,
Basalt-Low, Quartz-High, Quartz-Low), class = factor),
Sodium = c(27.3, 26.9, 25, 18.1,
4.67, 5.56, 10.7, 5.67
), SD = c(5.3851648071345, 2.42097317438899, 20.1618451536560,
15.2679766541317, 5.45435605731786, 8.09492296305393,
10.6183802907976, 8.06225774829855), Nobs = c(9, 9, 9, 9, 9, 9, 9, 9),
Lower =
c(25.5382783976218,
26.0818978307592, 18.2793849487813, 13.0217855597339,
2.84854798089405, 2.85724790120425, 7.12720656973412, 2.97924741723382),
Upper = c(29.1283882690448,
27.6958799470186, 31.7206150512187, 23.2004366624884,
6.48478535243929, 8.25386320990686, 14.2061267635992, 8.35408591609952)),
.Names = c(Position,
AltGeo, Sodium, SD, Nobs, Lower, Upper), row.names = c(1,
2, 3, 4, 5, 6, 7, 8), class = data.frame)
tmp$PosNum - unclass(tmp$Position)
tmp
(labs - unique(tmp$Position))
# plot factor levels in seperate panels
xYplot(Cbind(Sodium,Lower,Upper) ~ PosNum|AltGeo, data=tmp, nx=FALSE,
xlim=c(0.5,2.5),
ylim=c(min(tmp$Lower)-1,max(tmp$Upper)+1),
scales = list(x = list(at=seq(1, 2, by=1), labels = labs)),
xlab=Position, ylab=Sodium
)
Just out of curiousity, does replacing the 'xlim' and 'scales' arguments above
by
xlim = levels(tmp$Position)
do the same thing? It should with xyplot (which also allows the x variable to
be a factor), but xYplot may be bypassing that.
Deepayan
__
R-help@stat.math.ethz.ch mailing list
https://stat.ethz.ch/mailman/listinfo/r-help
PLEASE do read the posting guide! http://www.R-project.org/posting-guide.html
Re: [R] Problem with data frame when using xYplot?
Hi Deepayan!
Deepayan Sarkar wrote:
On Friday 13 May 2005 08:07 am, Sander Oom wrote:
An off list response from Mat Soukop (thanks Mat!!) provides an even
more elegant solution (see code below)! I have included the original
code, so people can decide whether to plot in a single panel or in
multiple panels. Now we have a fully functional workaround to get
plotmeans{gplots} for multiple factors using lattice! Great!
Just out of curiousity, does replacing the 'xlim' and 'scales' arguments above
by
xlim = levels(tmp$Position)
do the same thing? It should with xyplot (which also allows the x variable to
be a factor), but xYplot may be bypassing that.
You mean: xlim = levels(tmp$AltGeo)yes it does!? No clue how one
would ever get comfortable with all these options!
library(Hmisc)
library(lattice)
ltheme - canonical.theme(color = FALSE) ## in-built BW theme
ltheme$strip.background$col - transparent ## change strip bg
lattice.options(default.theme = ltheme) ## set as default
tmp -
structure(list(Position = structure(as.integer(c(1, 2, 1, 2,
1, 2, 1, 2)), .Label = c(Inside, Outside), class = factor),
AltGeo = structure(as.integer(c(1, 1, 2, 2, 3, 3, 4, 4)), .Label =
c(Basalt-High,
Basalt-Low, Quartz-High, Quartz-Low), class = factor),
Sodium = c(27.3, 26.9, 25, 18.1,
4.67, 5.56, 10.7, 5.67
), SD = c(5.3851648071345, 2.42097317438899, 20.1618451536560,
15.2679766541317, 5.45435605731786, 8.09492296305393, 10.6183802907976,
8.06225774829855), Nobs = c(9, 9, 9, 9, 9, 9, 9, 9), Lower =
c(25.5382783976218,
26.0818978307592, 18.2793849487813, 13.0217855597339, 2.84854798089405,
2.85724790120425, 7.12720656973412, 2.97924741723382), Upper =
c(29.1283882690448,
27.6958799470186, 31.7206150512187, 23.2004366624884, 6.48478535243929,
8.25386320990686, 14.2061267635992, 8.35408591609952)), .Names =
c(Position,
AltGeo, Sodium, SD, Nobs, Lower, Upper), row.names = c(1,
2, 3, 4, 5, 6, 7, 8), class = data.frame)
tmp$xvar - rep(1:4, each=2)+rep(c(-0.1,0.1), 4)
tmp
sp - list(superpose.symbol = list(pch = c(16,1), cex = 1))
xYplot(Cbind(Sodium,Lower,Upper) ~ xvar, groups=Position, data=tmp,
xlim = levels(tmp$AltGeo),
ylim=c(min(tmp$Lower)-1,max(tmp$Upper)+1),
xlab='AltGeo', ylab='Sodium',
panel = function(x, y, type, ...) {
panel.xYplot(x, y, type=p,...)
lpoints(x, y, pch=16, col=white, cex=2)
panel.superpose(x, y, type=p, ...)
},
par.settings = sp,
auto.key=list(columns=1, x=0.7, y=0.8, corner = c(0,0))
)
Deepayan
__
R-help@stat.math.ethz.ch mailing list
https://stat.ethz.ch/mailman/listinfo/r-help
PLEASE do read the posting guide! http://www.R-project.org/posting-guide.html
--
Dr. Sander P. Oom
Animal, Plant and Environmental Sciences,
University of the Witwatersrand
Private Bag 3, Wits 2050, South Africa
Tel (work) +27 (0)11 717 64 04
Tel (home) +27 (0)18 297 44 51
Fax +27 (0)18 299 24 64
Email [EMAIL PROTECTED]
Web www.oomvanlieshout.net/sander
__
R-help@stat.math.ethz.ch mailing list
https://stat.ethz.ch/mailman/listinfo/r-help
PLEASE do read the posting guide! http://www.R-project.org/posting-guide.html
Re: [R] Problem with data frame when using xYplot?
On Friday 13 May 2005 10:36 am, Sander Oom wrote:
Hi Deepayan!
Deepayan Sarkar wrote:
On Friday 13 May 2005 08:07 am, Sander Oom wrote:
An off list response from Mat Soukop (thanks Mat!!) provides an even
more elegant solution (see code below)! I have included the original
code, so people can decide whether to plot in a single panel or in
multiple panels. Now we have a fully functional workaround to get
plotmeans{gplots} for multiple factors using lattice! Great!
Just out of curiousity, does replacing the 'xlim' and 'scales' arguments
above by
xlim = levels(tmp$Position)
do the same thing? It should with xyplot (which also allows the x
variable to be a factor), but xYplot may be bypassing that.
You mean: xlim = levels(tmp$AltGeo)yes it does!?
No, I meant exactly what I wrote, and my comment followed this piece of code
(which you have deleted from your reply):
-
tmp$PosNum - unclass(tmp$Position)
tmp
(labs - unique(tmp$Position))
# plot factor levels in seperate panels
xYplot(Cbind(Sodium,Lower,Upper) ~ PosNum|AltGeo, data=tmp, nx=FALSE,
xlim=c(0.5,2.5),
ylim=c(min(tmp$Lower)-1,max(tmp$Upper)+1),
scales = list(x = list(at=seq(1, 2, by=1), labels = labs)),
xlab=Position, ylab=Sodium
)
--
No clue how one would ever get comfortable with all these options!
By reading the manual, of course :-)
Deepayan
__
R-help@stat.math.ethz.ch mailing list
https://stat.ethz.ch/mailman/listinfo/r-help
PLEASE do read the posting guide! http://www.R-project.org/posting-guide.html
Re: [R] Problem with data frame when using xYplot?
Sorry Deepayan, I forgot that the code moved on while you send your
reply. Below the simplified version using your suggestion and this time
based on the generic data used in the xYplot manual!
Maybe this example can be included in the manual, so next time people
will find the answer there. Or better still, you could provide a high
level function in 'lattice'. ;-)
dfr - expand.grid(month=1:12, continent=c('Europe','USA'),
sex=c('female','male'))
set.seed(1)
dfr$y - dfr$month/10 + 1*(dfr$sex=='female') +
2*(dfr$continent=='Europe') + runif(48,-.15,.15)
dfr
dfs - summarize(dfr$y, llist(dfr$continent,dfr$sex),
smean.cl.normal)
labs - unique(dfs$continent)
colnames(dfs) - list(continent,sex,y,Lower,Upper)
dfs$sexnum - unclass(dfs$sex)
dfs
xYplot(Cbind(y,Lower,Upper) ~ sexnum|continent, data=dfs, nx=FALSE,
xlim=levels(dfs$sex),
ylim=c(min(dfs$Lower)-1,max(dfs$Upper)+1),
)
dfs$xvar - rep(1:2, each=2)+rep(c(-0.1,0.1), 2)
dfs
sp - list(superpose.symbol = list(pch = c(16,1), cex = 1),
superpose.line = list(col = grey, lty = 1))
xYplot(Cbind(y,Lower,Upper) ~ xvar, groups=sex, data=dfs,
xlim= levels(dfs$continent),
ylim= c(min(dfs$Lower)-1,max(dfs$Upper)+1),
xlab=Continent,
panel=function(x, y, type, ...) {
panel.xYplot(x, y, type=p,...)
lpoints(x, y, pch=16, col=white, cex=2)
panel.superpose(x, y, type=p, ...)
},
par.settings= sp,
auto.key= list(columns=1, x=0.7, y=0.8, corner = c(0,0))
)
Deepayan Sarkar wrote:
On Friday 13 May 2005 10:36 am, Sander Oom wrote:
Hi Deepayan!
Deepayan Sarkar wrote:
On Friday 13 May 2005 08:07 am, Sander Oom wrote:
An off list response from Mat Soukop (thanks Mat!!) provides an even
more elegant solution (see code below)! I have included the original
code, so people can decide whether to plot in a single panel or in
multiple panels. Now we have a fully functional workaround to get
plotmeans{gplots} for multiple factors using lattice! Great!
Just out of curiousity, does replacing the 'xlim' and 'scales' arguments
above by
xlim = levels(tmp$Position)
do the same thing? It should with xyplot (which also allows the x
variable to be a factor), but xYplot may be bypassing that.
You mean: xlim = levels(tmp$AltGeo)yes it does!?
No, I meant exactly what I wrote, and my comment followed this piece of code
(which you have deleted from your reply):
-
tmp$PosNum - unclass(tmp$Position)
tmp
(labs - unique(tmp$Position))
# plot factor levels in seperate panels
xYplot(Cbind(Sodium,Lower,Upper) ~ PosNum|AltGeo, data=tmp, nx=FALSE,
xlim=c(0.5,2.5),
ylim=c(min(tmp$Lower)-1,max(tmp$Upper)+1),
scales = list(x = list(at=seq(1, 2, by=1), labels = labs)),
xlab=Position, ylab=Sodium
)
--
No clue how one would ever get comfortable with all these options!
By reading the manual, of course :-)
Deepayan
__
R-help@stat.math.ethz.ch mailing list
https://stat.ethz.ch/mailman/listinfo/r-help
PLEASE do read the posting guide! http://www.R-project.org/posting-guide.html
--
Dr. Sander P. Oom
Animal, Plant and Environmental Sciences,
University of the Witwatersrand
Private Bag 3, Wits 2050, South Africa
Tel (work) +27 (0)11 717 64 04
Tel (home) +27 (0)18 297 44 51
Fax +27 (0)18 299 24 64
Email [EMAIL PROTECTED]
Web www.oomvanlieshout.net/sander
__
R-help@stat.math.ethz.ch mailing list
https://stat.ethz.ch/mailman/listinfo/r-help
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[R] Problem with data frame when using xYplot?
Dear all, I am trying to plot means and error bars using xYplot, but I get an error message from xYplot which I can not figure out: Error in Summary.factor(..., na.rm = na.rm) : range not meaningful for factors The data frame (tmpNa) was created using aggregate. I have used dump to created the code below, which generates the same error. Can anybody tell me what is wrong with the data frame? Thanks in advance, Sander. library(Hmisc) tmpNa - structure(list(Position = structure(as.integer(c(1, 2, 1, 2, 1, 2, 1, 2)), .Label = c(Inside, Outside), class = factor), AltGeo = structure(as.integer(c(1, 1, 2, 2, 3, 3, 4, 4)), .Label = c(Basalt-High, Basalt-Low, Quartz-High, Quartz-Low), class = factor), Sodium = c(27.3, 26.9, 25, 18.1, 4.67, 5.56, 10.7, 5.67 ), SD = c(5.3851648071345, 2.42097317438899, 20.1618451536560, 15.2679766541317, 5.45435605731786, 8.09492296305393, 10.6183802907976, 8.06225774829855), Nobs = c(9, 9, 9, 9, 9, 9, 9, 9), Lower = c(25.5382783976218, 26.0818978307592, 18.2793849487813, 13.0217855597339, 2.84854798089405, 2.85724790120425, 7.12720656973412, 2.97924741723382), Upper = c(29.1283882690448, 27.6958799470186, 31.7206150512187, 23.2004366624884, 6.48478535243929, 8.25386320990686, 14.2061267635992, 8.35408591609952)), .Names = c(Position, AltGeo, Sodium, SD, Nobs, Lower, Upper), row.names = c(1, 2, 3, 4, 5, 6, 7, 8), class = data.frame) xYplot(Cbind(Sodium,Lower,Upper) ~ AltGeo, groups=Position, data=tmpNa) version _ platform i686-pc-linux-gnu arch i686 os linux-gnu system i686, linux-gnu status major2 minor1.0 year 2005 month04 day 18 language R -- Dr. Sander P. Oom Animal, Plant and Environmental Sciences, University of the Witwatersrand Private Bag 3, Wits 2050, South Africa Tel (work) +27 (0)11 717 64 04 Tel (home) +27 (0)18 297 44 51 Fax +27 (0)18 299 24 64 Email [EMAIL PROTECTED] Web www.oomvanlieshout.net/sander __ R-help@stat.math.ethz.ch mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide! http://www.R-project.org/posting-guide.html
