Latest Contributions by SteveLynch

Dean Firstly, what type of precip data, hourly, daily, monthly, annual, mean annual, etc.? Secondly, higher elevation does not always mean more rain, there are rain shadows, for example. So you may need additional info. In studies that I did many years ago I found that distance from the sea and surface roughness also played an important role. Also the rain-bearing direction. An extensive literature search will help 🙂 Regards Steve ... View more

Have you set your Processing extent = to that of the polygon? This is done via the Environment. Steve ... View more

It is in ArcGIS version 10.1 ... View more

Lauren If you are using ArcGIS 10 you can use CellStatistics. Input raster=small raster and in the environment set the processing extent=larger raster. Steve ... View more

While doing a search did you find http://resources.arcgis.com/en/help/main/10.1/index.html#//009z00000078000000 ? Have you looked at the 2 references ? Regards Steve ... View more

also if you are using ArcGIS 10, you could use CellStatistics and set the extent to Union of.. see http://forums.arcgis.com/threads/59895-Combine-Rasters-using-Con-Expression-Error?highlight=cellstatistics Steve ... View more

Please see http://forums.arcgis.com/threads/34053-Interpolation-for-Precipitation-Grid ... View more

Dean A Geostatistical layer cannot be masked per se. You can, however, clip the data frame. (in ArcMap, right click the Layers in the TOC and choose Data Frame Properties and supply a clipping polygon). In 10.1 you can supply a MASK via the environment when using the GALayerToGrid tool. Pre 10.1, you can use Spatial Analyst's Plus tool to add zero to your exported raster and supply a MASK in the environment. Steve ... View more

You need to set the output extent = max of the input rasters Steve ... View more

Look at the Zonal Statistics tool in the Spatial Analyst toolbox Steve ... View more

Have you tried uncheckking the "Simplify polygons" option ? Thanks Steve ... View more

The text file must contain 700 * 1300 legit values from the 6th row onwards. It'll then use the first 700 for the northern most part of the raster and so on with the very southern most part coming from the very last 700 values. It appears that you have non numeric values somewhere after the 6th row or you don't have 700*1300 values. Steve ... View more

It is not the correct format, please see the help for the correct format. You can't have strings and semicolons. I.e     NCOLS 3     NROWS 2     XLLCORNER 378922     YLLCORNER 4072345     CELLSIZE 30     43 2 45     35 45 65 Steve ... View more

Chris What version of ArcGIS are you using? Are you only using contour input? What is the average spacing between contour lines? What cell size are you using? Have you tried using stream/rivers as input? How many iterations are you doing? Are your data in a projected coordinate system? Thanks Steve ... View more