similar to: Raster extract by polygon generating NAs

Dear members, How can I read and plot an ArcGIS raster file into R ? The file has extension .aux and contains floating point bathymetry data. The purpose is to create a spatial model in R that uses ArcGIS map data. I have managed to read and plot various shape files into my R project, but I am stuck with this now. I am new to this list and also to R, so any help would be much appreciated. Many

Hello R-Group, I am new working with netcdf files and the raster package in R.I am trying to read in a netcdf file using the package "ncdf".I am able to get the lat, lon and parameter I need and can plot using fill.contour.Ultimately, I am trying to create a .asc file to reafd into GIS.I am using the package "raster" to read the parameter.When I read in with

Hello: I am using R raster package to replace ArcGIS when processing multiple shp files. However, when I export R raster back to ArcGIS, it couldn't recognize R raster file correctly. For example, I used {raster} package and got a RasterLayer as followed. class : RasterLayer dimensions : 8280, 18480, 153014400 (nrow, ncol, ncell) resolution : 0.008333334, 0.008333334 (x, y)

Can someone help me out with a "small" problem? I've started using netcdf files recently, and I want to extract the grid id and also the coordinates from a HIRHAM netcdf file. I know how to extract a slice of dataset both in space and in time and I also know the area that this file should cover, however I have no idea regarding the reference for both LAT/LON and RLAT/RLON. I tried

Hola, No tengo mucha idea de esto y hace tiempo que no lo uso. Unas ideas: - ¿Puedes hacer un summary(prueba) para ver si los datos que tienes dentro del raster son los que te está representado? Eso te permitirá saber si el problema esta en raster() o en plot() - Puede que al hacer plot() te haga categorías en lugar de asignar un color para cada valor, igual el parámetro col de plot() te ayuda. -

Hi all, I have some concerns regarding the rasterize option in R and I would like to know if the fun=max in rasterize in R provides similar results to the one achieved by using "Polygon to Raster using maximum-combined-area" in ArcGIS? I'm trying to rasterize a habitat layer to a raster of 10m spatial resolution using the function 'max' (e.g. r <- rasterize(ht, r,

Hi List, I have a raster and a polygon with attribute ID and Class. I want to have the fraction of each class present in each pixel of raster. I have use the raster::extract to get the value and weights as below. ex<-extract(raster,polygon,weighted=TRUE) this gives me [[1]] value weight 13943 0.24 13958 0.02 13959 0.84 13960 0.19 13987 0.03 13988 0.31 13990 0.30 [[2]]

Hi, ? I am trying to write a shapefile with projection. I have my data in a data.frame called try and consists in xy coordinates and a numerical attribute value z1. ? Libraries loaded are: sp, rgdal, raster, maptools ? head(try) ???????? x?????? ??? y??? ? ? ? ? ? ? ??? z1 1 610237.1 ???????? 3375751 ???????????? 8.221 2 610236.1 ???????? 3375750 ???????????? 8.153 3 610236.1 ????????

Hi, You might get more help from the R-sig-geo list, which is devoted to spatial topics. However. The *.asc file is an ArcGIS raster export format. You should use whatever the appropriate import commands are for your own gridded rainfall data. If you have a different format, you might or might not be able to import it directly with raster. ?raster will tell you more about the kinds of formats

Hi, I am trying to predict the habitat suitability of lobster with GAMs. I need to produce a map in ArcGis of the predicted densities. I did some search and the function predict.gam seems to do the job. Is this the right way to do it? when you apply the function you get the predicted values (different from your input data points) but I do not understand what is the procedure with the spatial

Dear list, I have to compare two digital elevation models in raster format (geotiff). I then have to calculate the differences in altitude for each cell and make some statistics (basic as mean, median, std, range but also more "advanced" as RMSE) on that. I do not know very much how to proceed: 1) is it possible to import the geotiff in R? If so with which package? if not which is the

Hi, I am working with a SpatialPolygonsDataFrame of many islands. There are a lot of polygons (islands) composing my SpatialPolygonsDataFrame. I want to extract the elevation of each island. I need to separate the different polygons (like dissolve function in arcgis), to have the elevation of each island. Do you have any idea how can I do that ? I already read a lot of forum, and read the

Dear all, I have been trying to speed up a process we have been done in ArcGIS. We have to read a single layer TIFF (monochrome image) in . For this, I have used the "rtiff" package. After reading the TIFF file, I compared the raw values for each pixel that I have in ArcGIS to the ones obtained in R. In ArcGIS I have discrete values in the range 0..255, while in R I have continuous

Hello every body, i?m testing some w32 apps with wine and I found some problems. Trying to install ArcGIS (My first installation), I had the following error: Need internet explorer 6. Well I installed IE 6, and continue installing ArcGIS, it was installed succesfully, but it installed Phyton, and throw some problems. Well finally installed I run ArcGIS and the fonts were crazy, I didnt see

On R 2.15.2 and ArcGIS 9.3.1, it works for me in ArcCatalog but you have to follow the particulars here: http://webhelp.esri.com/arcgisdesktop/9.3/index.cfm?TopicName=Accessing_delimited_text_file_data For example: write.table(test, '***.tab', sep = '\t', row.names = F) The extension .tab and sep = '\t' are required for text files. Didn't test row.names=T but I

Sorry, I did not make my question clear. Since I have a point theme with many points, some of them may clump together. the problems here are: 1. how to find clumps in a point theme? 2. the convex-hull extension I found only deal with all the points in a theme at each time? how to make each convex hull around each point clump automatically? Thanks. Xiaohua On 5/12/06, Bob Booth <bbooth

Fwiw the engine behind geom_raster needs explicit observation-per-row form for input (with no structural normalization), so conversion to points is perfectly proper here, albeit confusing in context. (It's closer to what graphics devices actually use ultimately, but the expansion is laid out very early in ggplot2 because there's no standard for intermediate forms.) Cheers, Mike On Wed,

It seems within the last ~3 months Ive been having issues with writing text or csv files from a R data frame.  The problem is multifold and it is hard to filter  out what is going on and where the problem is.  So, Im hoping someone else has come across this and may provide insight.   My current settings for R: R version 2.15.2 (2012-10-26) Platform: x86_64-w64-mingw32/x64 (64-bit) locale: [1]

Dear R users, I need to produce rainfall maps using R. I know that this is possible, I looked though the web, I found the example below reported (the author is Andrew Tredennick). I would ask you if this is the most performing way to make rainfall maps; if yes would someone be able to give me an example of how file.asc and pointfile.csv should be? If no would somebody please show me another way

Hi everyone, I wonder if anyone knows the reason why the outputs of the same reprojection in r and arcgis are different?. The magnitude of the change can be up to 40 km in the poles. Basically, I have a database of points equally separated by one degree over the globe. In ARCGIS, I am projecting the data in GCS-WGS-1984 and then reprojected it to Berhmann to ensure equal area