Latest Contributions by ChrisDonohue__GISP

I don't recall any book signings during the several times I've been to the Conference, but that may be due to the mind-boggling amount of activities going on. I agree with Chris Sergent - Jack is a very down-to-earth guy.  He's not your typical corporate executive type.  He's busy, but if you can grab him, he is very approachable and enthusiastic. Chris Donohue, GISP ... View more

Let me see if I can help clarify part of this, as it is not obvious.  ArcMap takes the first data set added to it and inherits that data sets projection/coordinate system for the Data Frame in ArcMap.  For example, if I open a new MXD and then add a shapefile that is in "UTM 10N NAD 83" in ArcMap, the Data Frame will now be automatically set to " UTM 10N NAD83".  When you are checking data to figure out what its coordinate system should be, you want to add it to a new ArcMap mxd that has not had any data added previously or had a projection/coordinate system defined.  This way you can get a real sense of the data's location.  If, however, one adds it to a MXD where it has already inherited or been assigned a projection/coordinate system, ArcMaps "project-on-the-fly" will be in operation, and the results will be not representative. Chris Donohue, GISP ... View more

I think James' solution seems to be the best given what you are trying to do.  Representations can be very effective, but are often very time-consuming to create, so are usually not worth it for displaying information unless you forsee using it over and over. Chris Donohue, GISP ... View more

The Cropscape FAQ offers this explanation: Common User Questions Is the CropScape/Cropland Data Layer available in a shapefile format? We do not offer the data in a vector format, such as shapefile. The Cropscape/CDL data can be downloaded in a raster-based GeoTIFF file format and used in most common GIS software. In ESRI ArcGIS you would most likely require the 'Spatial Analyst' extension to perform any in-depth GIS applications using the GeoTIFF file. And any common image processing software, such Erdas Imagine, ENVI or PCI, should be able to perform basic image processing/GIS applications using the GeoTIFF file. This type of pixel-based data does not lend itself to being converted to vector since the resulting polygon file would be enormous. Depending on the size of area you are studying it is technically possible to convert Cropscape data to a shapefile, but it would have to be a rather small area such as a single county or smaller. http://www.nass.usda.gov/research/Cropland/sarsfaqs2.htm#Section3_15.0 Chris Donohue, GISP ... View more

Hmmm, this file is a bit problematic, as says it will extract out to 5.99 Petrabytes, which requires a bit more space than I have free Also, it appears to be a raster image.  I suspect it is as it has an .rrd file. I found this explanation on the web: IGE file extension - Erdas Imagine Large Raster Spill file What is .ige file? File type specification: Bitmap image file type The ige file extension is related to ERDAS IMAGINE, a geospatial data authoring software, and used for so called Large Raster Spill files. When creating images requiring more than 4GB of disk space in Imagine a two file dataset is created. The .img contains the traditional superstructure, but the actual image data is kept in a separate non-HFA file format, normally with the extension .ige. This is presumably done to get around the 32bit file offset limitations of HFA format which makes it impossible to address large images. IGE file extension - Open, view and convert .ige files So I don't think this is a shapefile as you expected.  However, I can't open it to verify this. Chris Donohue, GISP ... View more

Is the file you downloaded this one?  Just wanted to confirm, as it will take a while to download. Click to download the national 2014 CDL zipped file National 2014 CDL (1.4 GB) Chris Donohue, GISP ... View more

Could you post the download link from where you got the data?  This way we can take a look at it to help you answer your question. Chris Donohue, GISP ... View more

Post quick, before the last Contests winners get online - this could be a golden opportunity for a brief moment of fame for being on the top of the list!  Chris Donohue, GISP ... View more

If one Dissolves by the field "SubRegion" the results from the field "Sub_Regi_1" will be lost.  For example, in the table image posted, Dissolving all of Sub_Region = 1 will essentially collapse the 4 records to one. One potential way to get around this is to do any calculations before doing the Dissolve.  You could iterate through the values of "SubRegion" (using Modelbuilder or Python) and do the necessary calculations, the results of which could be placed in new fields.  Then do the Dissolve.  You may have to join back the table with your calculations to the feature class result of the Dissolve (using "SubRegion" as the key). Chris Donohue, GISP ... View more

One way you can make this work with Modelbuilder is to make 3 models: 1.   A model with Iterator #1 2.   A model with Iterator #2 3.   A model that links the two.  You then run this one, which then runs the first and second models. Here's an example (somewhat messy, I admit, but it shows the basics).  The Iterator models are the ones called "Submodels".  Note - use a Precondition to trigger the second model after the first completes. Chris Donohue, GISP ... View more

If have a File Geodatabase or Personal Geodatabase, one way to resolve lock issues is to run the Compact (Data Management) tool.  While it normally is used to make geodatabases perform more effectively, it also explicitly releases locks as part of its functioning.  I've managed to solve several lock issues with this tool. ArcGIS Help (10.2, 10.2.1, and 10.2.2) Run it from ArcCatalog Make sure ArcGIS and all other GIS applications are closed. Note the this is not the same as the Compact tool listed under Administrative tools.  The Administrative tools one has limited lock-clearing capability. There could be a variety of issues causing the locks - this tool will solve existing locks, but not prevent new ones.  If you continue to get locks, more troubleshooting will be needed. Chris Donohue, GISP ... View more

Besides the ideas mentioned above, you could also split out the polygons into individual files with Modelbuilder. ArcGIS Help 10.1 -Note that there will need a unique ID for each polygon so it can be split out correctly.  Depending upon your needs, this could be by crown size or by individual polygon (I wasn't sure from your posts above which is needed). -The process is essentially Select and Export. -An Iterator provides the means to loop through each record. ArcGIS Help 10.1 -Optionally, you could add an "In-line Variable" to distinctively name the new outputs. ArcGIS Help 10.1 Chris Donohue, GISP ... View more

I bet Melinda Morang (ESRI Staff/Network Analyst expert) knows the answer. (when she logs on she will get a notice that her name is mentioned and will see your post). Chris Donohue, GISP ... View more

The two easiest solutions: Try exporting to your local C: drive.  This will bypass potential network slowdowns. Export to a tiff at the dpi you want.  Then use Photoshop or another image program to create the PDF.  The ArcMap pdf creation process is unfortunately not the most efficient way to make PDFs. Also, something not-so-obvious to keep in mind in exporting via ArcMap: - Once you apply a transparency to a layer, all the layers below that one in the Table of Contents will become rasterized on export.  So if one has an mxd with a dozen layers and the top layer has transparency applied, all the information will be exported as if it was raster, even vector linework!  This is very time consuming and memory intensive, not to mention that it creates huge files. You can check this if you like by turning off all the transparency and then re-exporting and see the difference.  The other classic way to see this is load a dozen vector layers into a new mxd, export, then make the top layer transparent and export.  The second export will take much longer to process and will be huge.  And if you open the second file in Adobe Illustrator, all you will see is a raster.  Whereas the first export will still have vector linework.  Note that there was no raster layer in the mxd when you exported. Chris Donohue, GISP ... View more

To elaborate on one of Sephe's comments, in ArcGIS, check whether the field is fully displaying, as often it truncates or rounds the display of the data though the data itself is actually untouched. To do this, go into the field properties and check on the display properties.  I don't have ArcGIS in front of me at the moment, but if I remember correctly one has to click on the ellipsis (...) to open part of the display settings, which is not so obvious.  You can then increase the amount of digits displayed. Chris Donohue, GISP ... View more