Monthly Archives: August 2011
The latest service pack for ArcGIS 10.0 is scheduled to be released in October, 2011, and includes many fixes for targeted issues.
If you have any feedback or questions regarding these fixes, please post in the ArcGIS Resource Center Forums. Esri will be monitoring these forums and respond to your feedback.
If you have additional enhancements or ideas that you would like to see included in future service packs or releases, please post them on the ArcGIS Ideas site.
Trimble has released an update for GPS Analyst v2.40 (TGA240Update003) in response to the Esri reported issue SPRT00000726462: Start Editing on GPS Analyst Toolbar Causes ArcMap to Crash.
The TGA240Update003 is available both when you install GPS Analyst for the first time (it is automatically offered as a separate download), and when you already have it installed and use the option “Check for New Updates Now”.
- Denise K.
Recently, you helped ArcGIS Ideas reach a few big milestones — Your ideas count passed the 3,000 mark, and the vote count crossed the 50,000 mark! To celebrate your enthusiastic participation, we’re excited to bring you the new, refaced ArcGIS Ideas site.
Our existing Ideas users will see the following key enhancements:
- The site has a cleaner look and feel.
- Categories now collapse into a group for better navigation.
- Recent ideas, Under Consideration ideas and Implemented ideas are shown under different tabs on the home page.
- The community’s recent activity is shown on the home page.
- The “My Ideas” page provides a better representation of your activity, including the number of ideas submitted by you, as well as the number of the ideas that you’ve submitted/voted on that have moved to “Under Consideration” or “Implemented” status.
We have added Frequently Asked Questions (FAQs) that will help you get answers to common questions while using Ideas.
We thank you for your continued support for ArcGIS Ideas and hope you’ll continue using this site to provide us with valuable input to improve our products and services. We look forward to receiving your comments and feedback on the site. Send this using the “feedback” link that’s on the bottom of all the Ideas pages.
We’re making some changes to our support site search, based on user comments, to enhance the overall experience on the site.
Effective immediately, you can experience the following update in our search at http://support.esri.com/.
Less omitted results: While searching for commonly-used terms, you may have previously seen a message: “In order to show you the most relevant results, we have omitted some entries…” (see the image below).
We have made this update to the Search Engine Results Page, enabling all results to be shown for the following repositories:
- Data Models
- Technical Articles
- Patches and Service Packs
- Product Documentation
- Samples and Utilities
- White Papers
Our belief is that this update will vastly improve the search experience for our users and will also help you find what you’re searching for quicker. We’ll consider removing this filter for all repositories, depending on the future feedback we receive.
Want more changes? Use that feedback button because we are listening. Also, keep an eye on the Esri Support site, because we’ve got plenty of other enhancements coming soon!
- Esri Support Services
How to add different-sized rasters with NoData Values
One of the most common forum topics is on how to add two rasters with different spatial extents and get a result more than just where the two rasters overlap. Well, the reason the result is only those areas has to do with null values.
There are environment variables to modify to ensure that the rasters line up (snap raster) and the extent is preserved during the process (Spatial Extent). Fixing the environment setting alone will still not fix the output of the process. If you modify the spatial extent to match the “union of inputs”, the output raster will have the correct spatial extent, but the only values will be the values where the two rasters overlapped. So what is going wrong?
Obviously it is the pixel values … or, wait, I guess it isn’t that obvious. Try this piece of wisdom provided by forum poster and Product Engineer, Eric R.
Pixel value + NoData Pixel = NoData Pixel
Pixel value + 0 = Pixel value
Pixel value + Nothing (because your extents are different) = Nothing.
You may be asking, “What is actually happening? Are the values being used in the analysis or not?” Well, the answer is they will be as long as part of that equation doesn’t include a null value. If there is a null value present that will make the output null, then the output will not be correct.
The next question is how to fix it. Bear in mind, both solutions require you to make the rasters that are being used as the inputs match in spatial extent, pixel registration and cell size. You can use the Copy Raster tool and set the appropriate environment settings to accomplish this. Once you have corrected the rasters, then there are two options depending on the desired output,
1. Set the NoData values to a value of zero, so that when they’re added together, the output will have the correct spatial extent and values from both rasters.
Con(IsNull(“RasterSMALL”),”RasterBIG, (“RasterSMALL” + “RasterBIG”))
To recap, there are options to handle the NoData cells. Depending on what output you’re trying achieve, there are different techniques. It’s also important to understand the effect that NoData has when used in raster calculation.
There is a related forum post that discusses using Python to sum multiple rasters together: Calculate sum of 2334 raster layers.
Jeff S. - Geodata Raster Support Analyst