By Kenneth Field, Esri Research Cartographer
In the lead up to London’s big sporting event in July 2012, the symbolic torch will travel the length and breadth of the United Kingdom. The route has been designed to maximize the opportunity for the UK population to view the torch as it makes its way, across 70 days, stopping at over 1000 locations where bearers will parade the torch locally. The torch relay event web map provides a time aware window on the event for locals to follow and for more distant observers to explore.
Whether you’re working with an existing application, or you’re planning a new app, unit testing provides an efficient, dependable way to verify that your code functions as expected and ensure that your app’s features work. In a nutshell, unit testing provides an automated way to target, test and validate specific components of an application.
As with most things JavaScript, Dojo has you covered. Specifically, the Dojo Objective Harness (DOH), which ships with Dojo, provides a framework for writing and running unit tests. The ArcGIS API for JavaScript team uses DOH to run unit tests throughout the development process to check that changes made to the API do not break existing functionality, and that new features accomplish their intended purpose. For more background on DOH and to get up to speed on its capabilities, please head over to the Dojo reference guide page for DOH. Please read through that page to get a better understanding of what DOH can do for you.
Now that you’ve had a brief introduction to DOH, let’s talk about how to use it with your custom modules as well as with classes shipped as part of the ArcGIS API for JavaScript. We’ve put up a page showing some simple unit tests that test functionality in a custom module as well as test some functionality in the ArcGIS API for JavaScript. The two tests for the esri.geometry.Extent object were pulled from the JavaScript API’s test suite of over 2,000 tests and are provided as an example of how to write a test that references esri modules. You can also download all of the required files from ArcGIS.com to run the tests locally.
One key change to make when using DOH to test code that references classes from the ArcGIS API for JavaScript is to change the dojoUrl variable to point to the Esri CDN-hosted version of ArcGIS API for JavaScript instead of a locally-hosted or other CDN-hosted version of dojo. Inside a script tag in runner.html, specify window.dojoUrl as the URL to the ArcGIS API for JavaScript:
window.dojoUrl = "http://serverapi.arcgisonline.com/jsapi/arcgis/?v=2.8";
By default, test modules are specified via a query string parameter called testModule. In the example linked above, the tests.all module is specified. That module rolls up tests from a couple of other modules that contain unit tests. By using modules, DOH allows you to run any number of tests, in any number of modules easily. For instance, to run only the tests in tests.TestModule1, specify that module as the testModule query string parameter. To see the specifics of how the various unit tests are implemented, please download the code from the link above.
Is this more work? Yes. Is it worth the trouble? Absolutely. While writing tests adds to the work required for app development, seeing tests run and pass instills confidence in your application that would otherwise be missing. By writing unit tests for your code, you can be sure that your app’s features and functionality work as expected. When tests are run throughout the development process, you know exactly how changes affect existing code and when things break. Unit tests do not completely replace manual, in-browser testing but they can go a long way to eliminating the majority of that work.
by Stephen Brown, Graduate Research Assistant, Dept. of Civil Engineering, University of New Mexico
Hydrologic data analysis frequently begins with a tedious march through the gauntlet of national data repositories, downloading data gage-by-gage until you have acceptable coverage for your region. The march continues as you homogenize the gage data to match locally collected values in an attempt to identify trends or simply graph the values for comparison. A majority of research time may be spent simply conducting data discovery and management.
Incorporating a Hydrologic Information System into your workflow can save you time and increase analysis opportunities. The Consortium of Universities for Advancement of Hydrologic Science, Inc. (CUAHSI) has developed an open source Hydrologic Information System (HIS) specifically to aid researchers with data discovery, analysis, and management.
Are you interested in learning about lidar and GIS at 10.1? A live training seminar will be offered next Thursday, May 24, 2012 to introduce Esri’s lidar capabilities at ArcGIS 10.1. There will be three offerings at: 9:00 am, 11:00 am, and 3:00 pm PDT (U.S. & Canada). To find out more information regarding the latest Working with Lidar Data in ArcGIS 10.1 seminar click the link below.
http://training.esri.com/Gateway/index.cfm?fa=seminars.viewDetails&course_id=178
Lindsay Weitz
Product Engineer, Software Product Release
In a previous blog, we described some of the basic checks in Data Reviewer that help validate features participating in a geometric network. Today, let’s discuss several advanced checks that provide an avenue to validate data in more specific ways. Once you have an understanding of how to configure these checks, they serve as powerful tools for maintaining data quality.
In the image you can see a casing that has been orphaned.
Finding Orphaned Features Using the Composite Check
There may be times when you want to validate data based on multiple conditions such as features that have relationships with two or more feature classes. However, if you create separate checks for each condition, you may not necessarily get the results you need. The Composite check in Data Reviewer searches for features that satisfy multiple conditions. The check combines Geometry on Geometry and/or Table to Table Attribute checks by feeding the results of one check into the next. The check configuration described below helps identify orphaned casings, for instance those that do not intersect laterals or mains.
With the release of ArcGIS 10, Esri provides users with a Land Records solution as a core part of the ArcGIS platform. This solution helps you produce great web maps, implement efficient workflows, and incorporate best practices from the land records industry at large.
The parcel maintenance solution has three key parts. First is the Parcel Editor toolbar, which is included with ArcGIS Desktop at the ArcEditor and ArcInfo license levels. This toolbar contains the tools needed to access and work with parcel data. The second part of the solution is the parcel fabric. This dataset manages the spatial and topological relationships inherent in parcel point, line, and polygon data. The third and final part of the solution is the Tax Parcel Editing map. It supports local government workflows and is a multiscale editing map that organizes the survey framework (Public Land Survey System [PLSS] and control), subdivisions, lots, tax parcels, and encumbrances in a fabric data model that can be used with the Parcel Editor toolbar.
by Paul Robinson, Water Resources Team Leader
Imagine being able to have an idea of where flooding issues are at the outset of a project. What if we could squeeze government dollars a bit harder and quickly map flood risk for a whole nation?
Making good use of available GIS data and new tools in the armory of our profession are rapid flood inundation models like Halcrow’s ISIS-FAST. The tool provides a quick assessment of flooding using simplified hydraulic principles to provide results up to 1000 times quicker when compared to other tools and methods available for flood inundation simulations – i.e. providing results in minutes as opposed to hours or days.
ISIS-FAST works by first identifying depressions on the floodplain before routing water through these depressions. Water depths in the depressions are determined by: volume of water flowing into that depression; level at which water can spill into neighboring depressions; and water level in neighboring depressions. ISIS FAST represents connectivity and volume filling effects on the floodplain, without having to represent detailed hydraulics.
In the last couple of weeks, the Imagery Blog discussed combining all your imagery bands into one raster. As mentioned previously, when you receive most satellite or aerial scenes they tend to distributed to you in several files – where each band is a separate file.
This week’s blog will discuss how the mosaic dataset can help you put your bands together. A mosaic dataset can put these scenes together into one logical geodatabase entity. Furthermore, it can mosaic all the scenes together as well.
A mosaic dataset can composite bands and also mosaic scenes.
Virtual 3D cities and geodesign in 3D are hot topics these days, and at the recent Esri Partner Conference and Developer Summit lead product engineer Mark Bockenhauer demonstrated some interesting capabilities which can potentially make your entire virtual city, including the software used to view and analyze it, completely portable – even pocketable.
We recently had a couple of questions in our inbox concerning map tips – the text that is displayed when you hover with your mouse over a feature – and here’s a summary of how they work.
