If  you don't have access to a 64-bit system that works with R and/or more than
4 gb ram you might try using a 3 gb switch in your boot.ini file on windows.
This is because windows will often conveniently limit you to 2 gb memory
because of its reserved overhead. 

http://www.microsoft.com/whdc/system/platform/server/PAE/PAEmem.mspx

I don't know if that switch works on Vista though since they want you to just
upgrade to 64-bit Vista and buy more RAM. 

On my XP Pro machine this switch has worked very well with Matlab and R in
allowing me more access to physcial ram. Maybe you have a copy of XP Pro laying
around and you can ditch Vista?

Adam


On Tue, Aug  5, 2008 03:40 PM, "Alessandro" <[EMAIL PROTECTED]>
wrote:
>
My notebook is:
>
> 
>
>Hp Pavilion dv6700 notebook PC
>
>Intel() Core �2 Duo CPU T9300 �2.50gHz 2,50GHz
>
>RAM: 4.00 GB
>
>OS: 32bit
>
>Windows (TERRIBLE!!!!!!!!!) VISTA
>
> 
>
> 
>
>Da: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] Per conto di
>Matt Oliver
>Inviato: marted� 5 agosto 2008 12.02
>A: Alessandro
>Cc: [EMAIL PROTECTED]; r-sig-geo@stat.math.ethz.ch
>Oggetto: Re: [R-sig-Geo] LIDAR Problem in R (THANKS for HELP)
>
> 
>
>you can try
>
>memory.limit(size=4000)
>
>only if you have 4GB of memory on the system
>
>This is not guaranteed to solve your problem though
>
>
>With big datasets like lidar, you are much better off getting access to a
>64bit system with a ton of RAM (>64GB).
>
>Cheers
>
>Matt
>
>
>
>On Tue, Aug 5, 2008 at 1:47 PM, Alessandro <[EMAIL PROTECTED]>
>wrote:
>
> 
>
>Hi All,
>
> 
>
>I am a PhD student in forestry science and I am working with LiDAR data set
>(huge data set). I am a brand-new in R and geostatistic (SORRY,
>my
>background it's in forestry) but I wish improve my skill for improve
>myself.
>I wish to develop a methodology to processing a large data-set of points
>(typical in LiDAR) but there is a problem with memory. I had created a
>subsample data-base but the semivariogram is periodic shape and I am not to
>able to try a fit the model. This is a maximum of two weeks of work (day
>bay
>day) SORRY. Is there a geostatistical user I am very happy to listen his
>suggests. Data format is X, Y and Z (height to create the DEM) in txt
>format
>
>I have this questions:
>
> 
>
>1.       After the random selection (10000 points) and
>fit.semivariogram
>model is it possible to use all LiDAR points? Because the new LiDAR power is
>to use huge number of points (X;Y; Z value) to create a very high
>resolution
>map of DEM and VEGETATION. The problem is the memory, but we can use a
>cluster-linux network to improve the capacity of R
>
> 
>
>2.       Is it possible to improve the memory capacity?
>
> 
>
>3.       The data has a trend and the qqplot shows a Gaussian trend. Is it
>possible to normalize the data (i.e. with log)?
>
> 
>
>4.       When I use this R code "subground.uk =
>krige(log(Z)~X+Y, subground,
>new.grid, v.fit, nmax=40)" to appear an Error massage: Error in
>eval(expr,
>envir, enclos) : oggetto "X" non trovato
>
> 
>
>I send you a report and attach the image to explain better. 
>
> 
>
>all procedure is write in R-software and to improve in gstat . The number of
>points of GROUND data-set (4x2 km) is 5,459,916.00. The random sub-
>set from
>original data-set is 10000 (R code is:  > samplerows
><-sample(1:nrow(testground),size=10000,replace=FALSE)
>> subground
><-testground[samplerows,])
>
> 
>
>1.       Original data-set Histogram: show two populations;
>
>2.       original data-set density plot: show again two populations of data;
>
>3.        Original data-set Boxplot: show there aren't outlayers un the
>data-set (the classification with terrascan is good and therefore there
>isn't a problem with original data)
>
>4.        ordinary kriging: show a trend in the space (hypothesis: the
>points are very close in the space)
>
>5.       de-trend dataset with:  v <- variogram (log(Z)~X+Y,
>subground,
>cutoff=1800, width=100)
>
>6.       map of semi-variogram: show an anisotropy in the space (0� is
>Nord=
>135� major radius 45� minus radius)
>
>7.       semi-variogram with anisotropy (0�, 45�, 90�, 135�), shows a
> best
>shape is from 135�
>
>8. semi-variogram fit with Gaussian Model. R code is (see the fig): 
>
>> v = variogram(Z~X+Y, subground, cutoff=1800, width=200,
>alpha=c(135)
>
>> v.fit = fit.variogram(v, vgm(psill = 1, model="Gau",
>range=1800, nugget=
>0, anis=c(135, 0.5)
>
> 
>
>R code:
>
> 
>
>testground2 <-
>read.table(file="c:/work_LIDAR_USA/R_kriging_new_set/ground_26841492694149_x
>yz.txt", header=T)
>
>class (testground2)
>
>coordinates (testground2)=~X+Y # this makes testground a
>SpatialPointsDataFrame
>
>class (testground2)
>
>str(as.data.frame(testground)
>
> 
>
>hist(testground$Z,nclass=20) #this makes a histogram
>
>plot(density(testground$Z) #this makes a plot density
>
>boxplot(testground$Z)#this makes a boxplot
>
> 
>
>samplerows<-sample(1:nrow(testground),size=10000,replace=FALSE) #select n.
>points from all data-base
>
>subground <-testground[samplerows,]
>
>hist(subground$Z,nclass=20) #this makes a histogram
>
>plot(density(subground$Z) #this makes a plot density
>
>boxplot(subground$Z)#this makes a boxplot
>
>spplot(subground["Z"], col.regions=bpy.colors(), at = seq(850,1170,10)
>
> 
>
>library(maptools)
>
>library(gstat)
>
>plot(variogram(Z~1, subground) #Ordinary Kriging (without detrend)
>
># if there is a trend we must use a detrend fuction Z~X+Y
>
>x11(); plot(variogram(log(Z)~X+Y, subground, cutoff=1800, width=80)
>#Universal Kriging (with detrend)
>
>x11(); plot(variogram(log(Z)~X+Y, subground, cutoff=1800, width=80, map=T)
>
>x11(); plot(variogram(log(Z)~X+Y, subground, cutoff=1800, width=80,
>alpha=c(0, 45, 90, 135)
>
>v = variogram(log(Z)~X+Y, subground, cutoff=1800, width=80, alpha=c(135,
>45)
>
>v.fit = fit.variogram(v, vgm(psill = 1, model="Gau", range=1800, nugget= 0,
>anis=c(135, 0.5)
>
>plot(v, v.fit, plot.nu=F, pch="+")
>
># create the new grid
>
>new.grid <- spsample(subground, type="regular", cellsize=c(1,1)
>
>gridded(new.grid) <- TRUE
>
>fullgrid(new.grid) <- TRUE
>
>[EMAIL PROTECTED]
>
>#using Universal Kriging
>
>subground.uk = krige(log(Z)~X+Y, subground, new.grid, v.fit, nmax=40)
>#ERROR
>
> 
>
> 
>
> 
>
> 
>
>
>_______________________________________________
>R-sig-Geo mailing list
>R-sig-Geo@stat.math.ethz.ch
>https://stat.ethz.ch/mailman/listinfo/r-sig-geo
>
>
>
>
>-- 
>Matthew J. Oliver
>Assistant Professor
>College of Marine and Earth Studies
>University of Delaware
>700 Pilottown Rd. 
>Lewes, DE, 19958
>302-645-4079
>http://www.ocean.udel.edu/people/profile.aspx?moliver
>
>
>       [[alternative HTML version deleted]]
>
>_______________________________________________
>R-sig-Geo mailing list
>R-sig-Geo@stat.math.ethz.ch
>https://stat.ethz.ch/mailman/listinfo/r-sig-geo
>





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