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August 20, 2009 - 23:34 by admin   Tags:

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Please provide software codes including the datasets used for testing and the detailed explanation of the processing steps and algorithms used. You are welcome to use our reference dataset.

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Volcano Maungawhau

August 20, 2009 - 16:07 by T.Hengl   Tags:
Short title: 
volcano

Maunga Whau (Mt Eden) is one of about 50 volcanos in the Auckland volcanic field. This data set gives topographic information for Maunga Whau on a 10 m by 10 m grid. A matrix with 87 rows and 61 columns, rows corresponding to grid lines running east to west and columns to grid lines running south to north.

Location

Volcano Maungawhau Auckland
New Zealand
36° 50' 50.586" S, 174° 45' 56.646" E
Available layers: 

- volcano_maungawhau.asc --- the 10 m DEM digitized from the topo map;

Grid definition: 

ncols: 61
nrows: 87
xllcorner: 2667400
yllcorner: 6478700
cellsize: 10 m

proj4: 
+init=epsg:27200
Lineage: 

Digitized from a topographic map by Ross Ihaka. These data should not be regarded as accurate.

> data(volcano)
> library(spatstat)
> LLC <- data.frame(E=174.761345, N=-36.879784)
> coordinates(LLC) <- ~E+N
> proj4string(LLC) <- CRS("+proj=longlat +datum=WGS84")
> LLC.NZGD49 <- spTransform(LLC, CRS("+init=epsg:27200"))
> volcano.r <- as.im(list(x=seq(from=2667405, length.out=61, by=10),
+     y=seq(from=6478705, length.out=87, by=10), 
+     z=t(volcano)[61:1,]))
> volcano.sp <- as(volcano.r, "SpatialGridDataFrame")
> proj4string(volcano.sp) <- CRS("+init=epsg:27200")
# str(volcano.sp)
# spplot(volcano.sp, at=seq(min(volcano.sp$v), max(volcano.sp$v),5),
+    col.regions=topo.colors(45))
> write.asciigrid(volcano.sp, "volcano_maungawhau.asc", na.value=-1)
Data owner: 
LINZ
Location: 
Volcano Maungawhau Auckland
New Zealand
36° 50' 50.586" S, 174° 45' 56.646" E
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