Harnessing GIS: Mapping Job Data with Esri's Online GIS
Professional Surveyor Magazine - July 2012
In the April issue, I introduced readers to a workflow for mapping a list of coordinates. This month, I’m offering something for those of you who are keeping track of jobs by their addresses. This article discusses the same tool—Esri’s ArcGIS Online—a free, cloud-based tool for mapping and understanding geographic information.
Mapping addresses is a much more detailed process than mapping coordinates, but much of that complexity is managed for you when you leverage an online GIS tool. You don’t need to worry about finding suitable street data, downloading parcel-based address databases, or matching your data with tax maps. All you need is a spreadsheet of your data. (If your data is in a database, you can easily export the information into a spreadsheet or CSV file.)
The hardest part of the whole process is making sure you have a spreadsheet in the right format. All of the major spreadsheet software packages (Microsoft Excel, OpenOffice Calc, Google Docs/Drive, and Lotus 1-2-3) offer the correct file format: a comma-separated value (CVS) file. You just have to make sure you remove blank lines (rows) and columns and have only a single line at the top defining the names of the columns. Figure 1
is an example spreadsheet.The item you need to worry about the most is the field names. Every field name must start with a letter and contain no spaces or non alpha-numeric characters (like dashes!). You can see in the example that all of the field names are either single words (Address, City, State, and Zip) or use the underscore character instead of a space or dash (Job_Ref).
You can have more columns, of course, but the essential ones are some sort of reference to the job and the address. You will notice the address is split into four columns: This is the best way to format your data. If you don’t have the entire address (including Address Number, City, State, and Zip), you can get away with less information, but the more you provide the greater chance you have of the tool finding the correct location.
The tool currently has a limit of 250 addresses per file. When you have your data in the right format, save or export it into the CSV format.
Creating Your Own Map
Point your web browser to www.arcgis.com
and click Sign In at the top, right corner. If you already have an ArcGIS Online account, just enter that information on the page. If not, you need to register with Esri. It is free and gives you 2GB of space for your maps and data uploads. Click Create an account and follow the instructions.
Once you have logged in, click the MAP button at the top of the window. You will see that all it takes is four easy steps to make your map (Figure 2
Skip Step 1 because the map will adjust automatically to show all of the jobs in your spreadsheet.
Step 2 involves picking a basemap and deciding what other layers you want to add to the map. Select a basemap by clicking the Basemap button and clicking a specific basemap. You have a variety of choices, including imagery, streets, topography, and shaded relief.
To see information about one of the basemaps, click the basemap to add it to your map, click the Details button, click the Show Content button, then click the arrow to the right of the basemap name. Click Description to see information about the basemap.
Once you have a basemap that you like, click the Add button and then click Add Layer From File. Click Choose File, then locate the CSV file containing your job data. Click Import Layer, and, after a few seconds, you will see a field-mapping dialog. This is where you make sure ArcGIS Online understands the address fields in your spreadsheet (Figure 3
If you click in each of the fields under Location Fields, you have a dropdown giving you the ability to choose the correct match for each field you have in your spreadsheet. Everything that isn’t part of the address should be set to Not Used, and, in the example, the Address, City, State, and Zip fields match up because they have the same name as the Location Fields. If yours don’t, match them up appropriately.
Click Add Layer when you are done and wait for the map to render (Figure 4
Making Changes to Your Map
The symbols used to show your address data can be changed. Move your mouse over the layer containing them (it will have the same name as the spreadsheet filename) until you see a small arrow. Click the arrow, and a menu will appear. Click Change Symbols, and you will see that you can show all of the addresses in one symbol, you can show addresses in several different symbols by using the Unique Symbols option (this would be useful if you had a status column or column for individual surveyors in a larger shop), or you can use Color or Size to vary the symbols by a numeric value field in the spreadsheet (like cost). Click Change Symbol to open a dialog box that lets you choose the type and size of the symbol you want to use (Figure 5
Clicking on the Map
If you click on any of the address points, you will see all of your spreadsheet data come up in a box. These are called Pop-up windows. You can change the way information is shown in a pop-up window: The best way is to click Help and enter pop-up into the search box. Making changes to the pop-up windows is the final step in making the map truly yours.
Click Save, give your map a title, tags, and summary, and then click Save Map. If you want to embed the map in your own website, go back and review the April article: The procedure is the same. With the ability to change basemaps for your map, you now have a great way of understanding another dimension of your data.
Ray Carnes stumbled across GIS in 1992 and has used it ever since for managing data, modeling, and analyzing geographic features and helping users understand how it helps them make better decisions. He has spent nearly 20 years (10 with Esri) providing GIS and IT technical support, training, implementation, and development services.
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