Latest Contributions by NeilAyres

The lakes and streams data do not need an attribute. The stream are supposed to be all digitized pointing downstream for drainage enforcement. The lake polygon boundaries adopt the minimum elevation value of the data surrounding them. See here : http://resources.arcgis.com/en/help/main/10.2/index.html#//009z0000006s000000 Good luck, Neil ... View more

As a rough approximation (ie on a sphere), just multiply your distance at the equator by the Cosine of the Latitude of where the data is to get the actual distance. And to further underline Melita's point, you should always georeference into the correct projected coordinate system of the data. Not directly into GCS. Good luck, Neil ... View more

What format are these rasters? Are you saying that after using the calc statistics tool, the values shown under properties are still as they were? It is possible that the directory or file setting are set to "read only". Modify this using the normal file explorer. I have seen in the past that calc statistics can run and complete normally, but fail to update the metadata files. Good luck, Neil ... View more

Interesting data! You can certainly set the cellsize and search radius to be the same in each case, you can see that. What is the scale across that map?. You might need an output with submetre resolution. You might consider creating a mask / snap raster covering the extent of all the data, with a particular cellsize and alignment. Then using the environment settings, snap each kernel density output to that. Good luck, Neil ... View more

Are you deleting the cursor somewhere... S_POL_ARTable = arcpy.SearchCursor(S_POL_AR) Something like this : if S_POL_ARTable:     del S_POL_ARTable Good luck, Neil ... View more

What doesn't work, what's the error message? You may want to try a double "\" when you save the output. ... View more

Project it into the same projected coordinate system as the image. ... View more

Errrr, doesn't Statistics_analysis work on tables or feature classes, not rasters. Try GetRasterProperties_management, this will return the MEAN, STDEV, MIN, Max etc etc Good luck, Neil ... View more

I did this a while ago. After much reading and messing about I ended up with a workflow like this : 1. Orthorectify each band. 2. Create a 4 band composite. 3. Do the pan-sharpening. See the pic as an illustration. Good luck, Neil ... View more

I tried defining each image with the same coordinate system, Don't just "redefine" the coordinate system. If necessary, reproject the images from one coord sys to another, including a datum shift if needed. But usually TM stuff is all on WGS84. So decide which years worth of data will be your "master" template in terms of pixel positioning. Then you could use the Raster Clip tool and set the environment snap raster and cell size to this master image. This should result in each one of the images having exactly the same extent and pixel alignment. Good luck, Neil ... View more

Check the file permissions using the normal windows explorer. You say this is grid format, so the directory above where the data is located as well. You could also load it into an fgdb where you know the permissions are read/write. Good luck, Neil ... View more

Another idea and probably more practical. Why not let ArcGIS do the classification and then access the value of the split values via the arcpy.mapping module. Check the RasterClassifiedSymbology class here : http://resources.arcgis.com/en/help/main/10.2/#/RasterClassifiedSymbology/00s30000005p000000/ That could work. Cheers, Neil ... View more

Noah, after I posted the pdf, I did indeed type up this piece of code as a python script. And tested it on a set of random numbers generated by python. The code worked fine. Havn't tested it again to see if it returns the same split values as ArcMap symbol editor though. However, I overlooked your original intention, classify an "image", and get those values into a reclassify routine. I found that the script worked well with, say, several 100's of records. But it doesn't scale very well. All those mat1, mat2 lists which it has to shuffle through. Once these get large, it gets very large. So what you might have to consider is to resample your slope raster using 1000 random points then use those values as an input into the Jenks classifier routine. Obviously converting the entire image (via raster to point or something), you will end up with too much data. Cheers, Neil ... View more

Check the file permissions of the data using the normal windows file explorer. Either the data itself or the directory it is in is probably set to "read only". Good luck, Neil ... View more