Latest Contributions by ChrisDonohue__GISP

‎01-06-2015

For starters, you will need to find out what the coordinate system is for it. I'm not familiar with the UK coordinate system(s), so don't know offhand what it should be. It's probably listed on the Ordnance Survey site here somewhere. In theory then if you have the image and the world file, you should be good to go. Chris Donohue, GISP

‎12-29-2014

Interesting analysis challenge. Some quick thoughts/rehashing: - It's almost like the reverse of Sink detection in hydrology. - I wonder if there is a way to detect the impassible areas and then aggregate them to create barriers. Chris Donohue, GISP

‎12-18-2014

Something to check on - the display settings of the mosaic. It may be that one or more of these settings is off for the mosaic, thus displaying it gray. When in ArcMap, right-click on the mosaic, then look at the Display and Symbology tabs. - In Display, check the "Resample during Display using:" - In Symbology, there are a variety of settings to look at: 1. Show: Stretched or RGB Composite 2. the Band assignments 3. Stretch Type 4. Apply Gamma Stretch Chris Donohue, GISP

‎12-18-2014

I have a Zoning map that my employer would like to be updated by changing the Zoning labels color from blue to black. It has over 1,300 Zoning labels and was done in ArcMap 10.2.1. The labels are annotation that have been saved to the mxd as map annotation (Convert Labels to Annotation, saved in the mxd). This was done as many parts of the map are very complex and labeling those parts in an legible way required the use of leader lines and lots of manual placement (Maplex was a good starting point, but wasn't cutting it). So the map is a mix of labels - some with leader lines, some without. Now here's the problem. I can manually select lots of labels at once with the Select Elements tool and change the color to black, but if any labels are selected with leader lines, the leader lines disappear when the color change is applied. Not sure why this is happening. Oddly enough, if just labels with leader lines are selected and the color change applied, the leader lines remain and there is no problem. So here's some questions: 1. Instead of manually editing this, Is there a script or other process that could do the color change? Some ideas: - A process that changes the color and doesn't have the side effect of dropping the leader lines? - Any automated way to query all the labels and select only the ones with leader lines? 2. If manual editing is continued, is there a different way to select many labels at once, change the color, and have it not drop the leader lines (instead of using the Select Elements tool)? Thanks in advance, Chris Donohue, GISP

‎12-17-2014

One way to do this is to use XTools Pro, a handy third-party software that works in ArcGIS. They have a function called "Split Polylines" that offers a multitude of ways to split a line, including by another feature class. XToolsPro, Feature Conversions, Split Polylines. Then choose "Split Polylines by another layer". http://www.xtoolspro.com/ They have a trial download available so you can test it out. Chris Donohue, GISP

‎12-17-2014

I haven't used ArcInfo Workstation in several years, but when I did I recall having to choose the correct mode. There are several: Included with ArcInfo are the following tools: Arc Arcdoc Arcedit Arcplot Arctools Formedit Grid Source: Arcinfo Workstation | software.ncsu.edu In terms of choosing which one, it boils down to what the your Arc Macro Language (AML) is trying to accomplish. For example, if the AML produces a map, use Arcplot. Many AMLs will also work in ARC: I'd try ARC as a first step. The general form to run the aml is this: Arc: &r amlname.aml input output Sorry if this is confusing - it's been a few years and I'm rusty. Chris Donohue, GISP

‎12-17-2014

A consideration: Are the specific expectations defined for the results? I ask as there could be several different ways to do this depending on what the expected final result is. For example, the expected result might be as simple as the PM2.5 rate spatially joined to each zip code, to a more complex surface analysis where you derive a raster surface from the PM 2.5 points using Spatial Analyst and then maybe even use Spatial Statistics. If you don't already have it defined, inquire with your instructor as to what the result requirements are. I bring this up as this is a common issue in the working world. People say "I need a map", but one often has to dig a bit to discover the particulars of what they really want. They already have in mind what they need, but don't always provide the many details/complexities that are needed to produce the desired results. What you want to find out often includes: expectations, methodology, assumptions, quality, accuracy, precision, exceptions, time constraints, etc. See if you can tease it out of your instructor/T.A. Also, since it is a class, I would advise making sure you make it clear from the beginning that your are looking for what the expectations of the results are, and that you are not trying to get the exact result out of them. Chris Donohue, GISP

‎12-16-2014

One way it could be done is by editing the data to make 2 parallell copies of the existing line (red) - one copy on either side. Then cut them to the desired length. About making a parallell copy of a line: ArcGIS Help 10.1 Chris Donohue, GISP

‎12-10-2014

Modelbuilder could be a way to go, assuming it is just a few simple queries. Here's the bare bones: Input data linked to a Select (Analysis) tool (with your first query in it), then the output linked to a Feature to Raster tool (or Polygon to Raster, Point to Raster, or Polyline to Raster). Then coming off the input data another Select tool for your second query, then the output linked to a Feature to Raster tool. Repeat for all the rest of your queries. if there are many queries it may be more effective to write code to loop through them instead of doing individual steps as I outlined above. Chris Donohue, GISP

‎12-10-2014

If your files are in a geodatabase, it may be that it has locked for several reasons. Here's some common ones: 1. It is being accessed by another user. View the geodatabase (carefully) with File Explorer. One of the files is a "lock" file, and part of the filename for that lock file is the computer that created the lock. 2. You are accessing it with more than one process. For example, you have ArcCatalog open separate from ArcMap and both are trying to access the data. Only have one open at a time. 3. The lock is not released from a previous round of geoprocessing or use (even though it should have released). This one is pretty common. I've talked to ESRI Support about this one recently and they admit this is an ongoing issue that they haven't fully resolved. The workaround to get it to release is to run the Compact (Data Management) geoprocessing tool. This tool releases all locks as part of its functioning. Note that this works differently than the "Compact" function in the Administrative tools, which is not as effective. Chris Donohue, GISP

‎12-10-2014

Dan has a point - maybe try geocoding them. I'm in no ways an expert on Geocoding, but I know there are quite a few geocoding services out there. While you may not necessarily be interested in the coordinate location of your address, the address result may very well be parsed for you as part of the process. Here's a site I remember people mentioning in a post here on GeoNet several weeks ago. Texas A&M Geoservices List of Online Geocoding Systems There may also be local geocoding services publicly available from government entities in your area. Maybe try the city and county governments of your area of interest. Chris Donohue, GISP

‎12-10-2014

A different idea - how about this as a possible approach - find an existing dataset of already-parsed addresses that include all the ones you have, then match yours to the parsed ones. Then output the parsed ones and pare down from there. I don't know exactly where you would find the parsed dataset(s), but given the proliferation of address information, geocoding, and the like, I suspect it could be feasible. Can anyone chime in on where specific sources of such already-parsed datasets could be found? Also, Derek, to help with this - what States are your addresses in? Chris Donohue, GISP [Edit: fixed some typos]

‎12-10-2014

If you haven't already tried it, you might be able to accomplish part of what you want with VB Script and the Left, Mid, and Right string functions. Whether this will be usable will depend on how your data is arranged; though from what you have depicted in your examples it would at least allow you to strip the zip code off. Check out the ESRI help, VBScript string functions section (part way down the page): Calculate Field Examples ArcGIS Help 10.1 As to culling out the City, that looks a bit trickier, given the variability in name-length of a city and the presence of multiple words for some cities. Off the wall idea - somehow tie in a search to a list of known cities that your data would include to then identify what to remove? Chris Donohue, GISP

‎12-10-2014

One possible solution to split the lines would be to use XTools Pro (http://www.xtoolspro.com/ ), a third-party add-in for ArcGIS. They have a function called "Split Polylines" that includes the option to split lines based on a second line layer. Their is a free version of XTools so one can try it out. Feature Conversions, Split Polylines, Split Polylines by another layer. Once you have your roadwork split, I believe you then could then do a spatial join to add the land value to the roads. Chris Donohue, GISP

‎12-04-2014

I'm not an expert on DEM's and their downloads, but here's some ideas based on my likewise flailing around on my infrequent downloads of them: An idea - there are several options in Download Data section of the National Map Viewer. One is "Click here to draw and download based on a bounding box." This could help limit your selection. Also, I believe the 30 meter DEM's match the same extents of USGS 24K Topo Quads (though I could be off on this). This may offer another way to determine which ones you need - there is a reference layer that can be displayed for the 24k Quads. Then the crux issue - once you go to the Download function, it returns a long list of different files, making it difficult to figure out which one needs. I believe for 30meter DEM's the files you want to download are just the ones listed as "1 arc-second" under the Resolution column. However, I'm not 100% sure on that - maybe someone who is more knowledgeable can chime in on that? Hope this helps, Chris Donohue, GISP

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Latest Contributions by ChrisDonohue__GISP

Re: ESRI World file (for GIS)

Re: Remove Islands

Re: Problem displaying mosaic (greyed out)

Leader lines dissapear if annotation color changed

Re: Splitting line features where they intersect features of another feature class.

Re: Issue trying to run AML

Re: GIS Lab Question

Re: Reshape overpass parallel to existing line

Re: Need help in creating a model

Re: Editing Error

Re: Trim strings at specific point using Field Calculator

Re: Trim strings at specific point using Field Calculator

Re: Trim strings at specific point using Field Calculator

Re: Splitting a line where it crosses polygon boundary

Re: How to find NED 30 needed for a watershed delineation?

Re: ArcGIS 10: Graphics won't display in Data View

Re: Can't set output as intermediate data

Re: Addressing - Plus Code or What3Words (W3W)

Re: How to label "_, Mount" as "Mount _" ?

Re: Raster/Vector Land use Analysis

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