Latest Contributions by SteveLynch

IDW uses a "line of sight" approach when barriers are used. The output extent, by default is equal to that of the input points. KernelInterpolationWithBarriers in Geostatistical Analyst, on the other hand, uses a "shortest route around" a barrier. Hope that this answers your question. Steve ... View more

If you are in lat/Long then you are in an unprojected coordinate system. I.e you are in a geographic coordinate system. You need to project you data! Steve ... View more

Camden If you load the raster (that you want to create a slope of) into ArcMap, what coordinates do you see in the bottom right of the view? Are they in feet or meters? What is the range of values in your raster, i.e. what are the min and max values? and what units are they in? -Steve ... View more

also remember to set the SnapRaster equal to your input raster otherwise Resampling (using nearest neighbor) will take place. -Steve ... View more

I did, but I get errors Traceback (most recent call last):   File "Z:\Extraction of Bands\Extraction\Python for extraction\Trial\ZonalStatsOverlappingPolys (2)\makeZones.py", line 170, in <module>     arcpy.CopyFeatures_management(inFeat, inFeatures)   File "c:\program files (x86)\arcgis\desktop10.1\arcpy\arcpy\management.py", line 2226, in CopyFeatures     raise e ExecuteError: ERROR 000210: Cannot create output Z:\Extraction of Bands\Extraction\Python for extraction\Trial\Scratch.mdb\50m_buffer_P_selection ERROR 000361: The name starts with an invalid characterFailed to execute (CopyFeatures). Failed to execute (ZonesWOverlap). Failed at Wed Oct 31 10:37:07 2012 (Elapsed Time: 8.00 seconds) Output in a geodatabase must start with an alphabetic character, yours starts with the number 5 ... View more

so you have 3 inputs to TopoToRaster 1) polyline and you've selected the type = Contour 2) point feature class and type = PointElevation 3) polygon feature class and type = Boundary Correct? Thanks Steve ... View more

Drew We don't use AdvancedArcMapSettings.exe (for Geostats) in ArcGIS 10.x anymore. I'm also not sure why you would need to do what you outline, where did you get the instructions from? To subset the data please search for the SubsetFeatures tool. Regards Steve ... View more

Mark Why don't you build pyramids on all your large rasters (or the one that you render often)? If you are creating rasters using Spatial Analyst you should run the Build Pyramids tool afterwards. The main reason that SA does not honor the pyramids setting is because of performance. You don't need pyramids for each raster that is created while doing your workflow. You usiually only need it if the output is large and will be rendered often. Hope this helps Steve ... View more

Spatial Analyst resamples using Nearest. Automatic resampling is triggered when there are different cell sizes, changes in processing environment and/or projection changes. What you could try is to copy your raster from the mosaic dataset into a single raster dataset, use CopyRaster. You will then see what the cell size is and this is basically the raster that'll be contoured. Regards Steve ... View more

The Mosaic dataset consists of many rasters with different cell sizes. Spatial Analyst, by default, uses the largest cell size when more than 1 raster is used. For example, raster1 has a cell size of 10 and raster2 has a cell size of 20. When you use the Plus tool the output will have a cell size of 20. This is what is happening with Contour, all the rasters are resampled to have a cell size=largest. Steve ... View more

Spatial Analyst's IDW ignores all the coincident data. For example, if you have 5 points with the exact same location, then SA's IDW will ignore points (2,3, 4 and 5) or it'll ignore points (1, 2, 3 and 4). This is stated in the help, see the 4th usage tip in http://resources.arcgis.com/en/help/main/10.1/index.html#//009z0000006m000000 Regards Steve ... View more

If you think that the Default max distance is not honored then you could do a simple test. Spatial Analyst does not honor the Geostatistical Analyst's Coincident points option as you and the documentation state. Accordinding to the Spatial Analyst IDW help Some input datasets may have several points with the same x,y coordinates. If the values of the points at the common location are the same, they are considered duplicates and have no affect on the output. If the values are different, they are considered coincident points. The various interpolation tools may handle this data condition differently. For example, in some cases the first coincident point encountered is used for the calculation; in other cases the last point encountered is used. This may cause some locations in the output raster to have different values than what you might expect. The solution is to prepare your data by removing these coincident points. The Collect Events tool in the Spatial Statistics toolbox is useful for identifying any coincident points in your data. -Steve ... View more

The question to ask is not about the horizontal spacing but what is measured in the z direction. You may have 2 points that are 3.5 ft apart but the elevation difference is 2 ft. Or you may be contouring temperature values, what do you make the interval? -Steve ... View more

Natural Neighbor interpolation does not support extrapolation outside the convex hull. If you used IDW, you would set the output extent to the mask feature class and use the Mask = mask feature class -Steve ... View more