Category Archives: GIS

Geographic Information Systems

Specify Editor for Python Scripts in ArcGIS for Desktop

Posted on by
Reply

Python, it is extremely useful for streamlining workflows and SOP for a multitude of tasks. This is particularly true for geoprocessing in ArcGIS. True, ModelBuilder can be used. More often than not, I find myself starting in ModelBuilder and finishing in Python simply because of the ability to have more control over processes and the ease of using iteration.

ArcGIS for Desktop 10 introduced the option to embed scripts into tools. Once embedded, editing is as simple as right clicking on the script in a toolbox and selecting edit. The default Python IDE, IDLE would open and from there the script could be edited.

After installing ArcGIS for Desktop 10.1 Prerelease, I discovered when choosing to edit an embedded script, the script opened in Notepad. This was not acceptable. Fortunately setting the editor is an easy change. Continue reading →

An IDE with code assist for the ArcGIS JavaScript API

Posted on by
Reply

For a multitude of reasons, I want to figure out how to work with the ArcGIS JavaScript API.  It has to do with mobile devices, lack of need for plugins and mostly because this is the direction the web is going long term. After all, HTML5 really is just a combination of html, CSS and JavaScript. Granted there are a few other goodies thrown in, but by and large, HTML5 is little more than an extension of these existing technologies. For these reasons, I want to learn to build web mapping applications using what is going to be the future.

Once deciding on this, another vexing conundrum presents itself. Unlike Flash and Sliverlight, which Esri has web mapping API’s for as well, there is not just a single integrated development environment (IDE) with code assist built in. Adobe distributes the Flash Builder IDE and it has some great code assist built in. Microsoft’s Visual Studio provides outstanding code assist for developing Silverlight.

The best IDE to use for JavaScript? Simply typing JavaScript IDE into Google brings up a flood of blog postings arguing this exact topic. The first hit however, above all these blog postings, is a direct link to Aptana Studio. Cross referencing to the ArcGIS Resource Center, I managed to unearth a help document with rather simple directions for using the ArcGIS JavaScript API with various editors. Continue reading →

Use ArcGIS.com to Create Custom JavaScript Web Applications

Posted on by
Reply

Esri has released web application builders for both Flash and Silverlight. However, for those wishing to stay away from these plugin dependent solutions, at first glance, it may appear there is little other option than starting from scratch and building an web application from scratch. Fortunately this is not the case. There are some great templates available on ArcGIS.com. Using these templates you can create a JavaScript web mapping application in a very similar way to the Flash and Silverlight builders.

Today I created a custom JavaScript web mapping application depicting piracy trends in the Arabian Sea without writing a single line of code. To create the same type of map, all you have to do is create three maps on ArcGIS.com, save them in your profile and use one as a starting point to create an application. Continue reading →

Create List of Unique Table Values using Python for ArcGIS Analysis

Posted on by
3

Necessity is the mother of invention and as of late, this means I have learned to use Python with ArcGIS. Early on, an issue I ran across was needing a list of all unique values in a field to be used in further analysis. Unfortunately there is not a pre-built method for this. Still, it did not take long to figure out the following function to accomplish this. Continue reading →

Iranian Ballistic Missile Range

Posted on by
Reply

Being a GIS geek, when reading the New York Times and The Economist on my iPad, current events in the Middle East always get me to thinking about how the geography all fits together. During the last few weeks and especially the last few days, tensions with Iran are at an all time high. Out of curiosity, I decided to further investigate using the toys at work, primarily ArcGIS 10 for Desktop, specifically the Multiple Ring Buffer geoprocessing tool.

To perform this analysis, first I need to establish what I am interested in, then find the data, prepare the data, analyze the data and finally output the results. The first part is easy, I know what I want to investigate. What areas are affected by the capabilities of Iran’s missile program? Continue reading →

Green Narrows Trail Map

Posted on by
2

Saturday 05 Nov 2011 at high noon the first racer will leave the eddy above Bride of Frankenstein on the Green River in North Carolina just outside of Hendersonville and head into the Narrows. Less than six minutes later, after descending over 500 feet through close to 10 class V rapids, the first racer will have finished the course. There rapids include friendly names such as Frankenstein, Go Left and Die, Gorilla and Scream Machine.

Every minute for the next few hours, another racer will start. All the safety is voluntary. There is no entry fee, no race sponsors and no prize money. The hike in to watch is a two mile walk ending with a quarter mile scramble dropping over 400 feet down into the gorge. Yet there will be over 200 racers and over 1,500 spectators for the Green Race, arguably the most prestigious extreme race in the country.

For the paddlers, getting there is not very difficult. However, for many of the spectators, this will be their first time trying to figure out how to get into the gorge. Although there is the generally accepted regular route down the Pulliam Creek trail, there are also other alternatives for getting into the gorge provided you do not mind walking a little further.

If interested in these other routes, want to figure out driving directions, or want to figure out another way in and out of the gorge, hopefully this map can be of assistance.


View Larger Map with ability to Print

Learn LiDAR Principles

Posted on by
Reply

LiDAR, if you work in GIS and pay any attention to digital elevation model (DEM) data, you have heard of LiDAR. Although many people know it has something to do with bouncing light off terrain and it is very accurate, many times knowledge ends there. Fortunately there is an outstanding resource for learning about LiDAR.

The USGS put together this very well organized resource. Although it focuses on applications of LiDAR for natural resources, over 75 percent of the lesson focuses on data collection methods, factors of accuracy and other technical aspects of LiDAR applicable to anybody who uses LiDAR data. Fully narrated with animated visual aids it is a great resource, one I highly recommend.

Run ArcGIS Models as Scheduled Tasks

Posted on by
2

ModelBuilder in ArcGIS Desktop is great. It enables the functionality of scripting without needing to know scripting. If you know how to use tools in ArcToolbox, typically in less than 30 minutes you can start automating redundant and long multi-step workflows using ModelBuilder. When it comes to taking this automation one step further, to have the computer automatically perform this workflow at a scheduled time, this is where difficulty can arise.

Windows cannot run a model as a scheduled task. Windows can however, run a Python script as a scheduled task. A Python script can run a model as a scheduled task. Using a three line Python script, a model can effectively be run as a scheduled task. The scheduled task calls the Python script and the Python script calls the model. The script looks like this…

import arcpy

arcpy.ImportToolbox(r"C:\pathToToolbox\Toolbox.tbx", "TBX")

arcpy.Model_TBX()

Continue reading →

Esri Disaster Response

Posted on by
Reply

Today I received an email highlighting the assistance Esri is standing by ready to offer for those assisting with disaster response. This email included a link directly to the Esri Disaster Response Webpage. Types of assistance include everything from software to data and even consulting. Most all types of disasters are included, wildfires, earthquakes, flooding, hurricanes and cyclones, spills and volcanic eruptions.  All you have to do is ask. Nothing is guaranteed, but if you have a need, you never know unless you ask!