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GIS Software Making a map of just your state
There are amazing things that we can do with ArcView 3.2, even if we're just beginners. One of my favorite activities is to break up maps and make custom graphics that I can incorporate into other things like tee-shirt transfers, multimedia projects, simple presentations, webpages - you name it - and you can probably work out how to make it. I'm going to provide you with the step-by-step pictures showing you how to do this. Once you learn the basic steps, you can use it over and over to sort out all manner of items. Let's get started. Start ArcView 3.2. You'll see the following dialog box:  I've clicked on create a new project with a new View. The easiest way to think about views is to consider them like maps that you're about to create. So, I'm going to create a new map - or a new representation of data in a visual format. When I clicked on OK, the following dialog box showed up. What we see here is an empty View. This is where I want you to start paying attention to the menu items and the toolbar icons in the picture. ArcView is one of those programs that is context sensitive. In other words, when you're not supposed to be doing something, it removes those options from the menus and the toolbar. On the one hand, that stops you from getting into trouble, but on the other hand, when you're learning a piece of software, you sort of recall where the command was and then suddenly it's not there any more. You'll be alright as long as you keep in mind that depending on what little box is active on the screen, your available choices will change. Click on the "plus" sign you see near my cursor in this picture. That's how you add a theme or layer of information to the map you're going to build.  The Add Theme dialog box pops up and now you need to navigate to where your data is stored. ArcView comes with a ton of data. I simply went to my ESRI folder on my computer and from there into the ESRIDATA folder and then opened up the USA folder. When I did that, I could see lots of choices on the left. I've clicked on Counties.shp (that's a shape file - more about that later) and then I'm clicking on OK.  I now have a rather squished map of the USA showing up. Notice that I have a check mark in the little box next to the title of this theme. That turns the theme on in the view. Otherwise, you can open up the data and it will be in your table of contents for your view (that's all the stuff on the left side of the View dialog box), but it won't be visible as a layer on your map. Let's go get the counties for a single state.  Look carefully at this picture and you'll see my cursor over a particular icon in the toolbar. We want to click on that to open the theme table for our active theme. If you can't see that button on your choices or it's greyed out, click on the theme in the table of contents on the left side of the View dialog box. That will make it active. Just having it checked doesn't mean that it is necessarily active. When there is only one theme and it's this big, you'll find it hard to tell when it is active - looking like a raised button - and when it's not. Let's get that theme table - or attribute table as it will be labeled - by clicking on the button that has the tiny grid on it.  The theme table or attributes of your theme is now open. If we're going to sort through the data in that table and pull out just the counties for the state we want, we have to query the table. In other words we have to tell it what we want. To build a query or ask a question, we click on the button that looks like a hammer. Make sure your Attributes dialog box is the one that has the bright blue band in the title bar. Notice that when you look at the icons and menu choices available in this picture, it is much different than the one just before. Remember - this software is context sensitive. So, if you can't find something, the software is telling you you're in the wrong spot. Think about where you need to be. 
Here's our query box and it tells us that we are building a query or question to ask about the counties. There is all sorts of information available in one of these tables, so pick the simplest and most efficient way to locate what you want. I don't know the special codes used to identify a state, but I do know the name of the one I want. I will search by State Name. You will see that term over on the left under Fields. Double-click on the field name you will be searching through. It will show up in the bottom of the box. Next, click once on the equals sign in the middle of the box because we only want one choice. Essentially, we're saying to the computer that the state name has to be a particular one. After the equals sign shows up in the bottom of the box, move over to the right side and look under Values. Scroll down until you see the state you want. In my case, that's South Carolina. Double-click on the state name and you'll see South Carolina appear in the bottom part. Your query or question is now set up. Click on New Set and look back at your attribute table to see what happened.  Here's our Attributes of Counties table and you'll see that any county located in South Carolina is highlighted in yellow. That tells you each of these items has been selected. We now need to tuck them into a nice, neat little group. Click on the Promote button next to the hammer. You can see my cursor on it in the picture below.  When we clicked on the Promote button, all the records were sorted into a solid chunk in the attributes table. Now, pay attention. This is where it can get tricky if you forget this step. You want to take those records you've selected and put them into their own file. We call that converting them to a shape file. After clicking on Promote and getting the records sorted, you MUST click on View so that it is now the active window or you'll never be able to get to this next command and you'll drive yourself insane trying to figure out why. Look in the picture below and you'll see that View now has a bright blue bar at the top. That tells you it is the active window. If you look back and forth between the picture above and the picture below, you'll see what I'm talking about. To go the next step, we must be able to get to the menu command Convert to Shapefile that is under Theme. Notice that when the attribute table is active (above), that command isn't available! When the View window is active, we can get to it.  Click on Theme and then Convert to Shapefile as illustrated in the picture below. That sequence of steps will take those records you have highlighted in yellow and put them in their own shape file which you will give a different name to than Counties - otherwise you'll overwrite the master file. Not a good idea! (If you do that, you can always get them back from your CD.) 
As soon as you choose the command Convert to Shapefile, ArcView brought up this little dialog box to ask you where you want to put it and what you want to call it. Here's another tip. Know ahead of time where you are going to save your file. A temp directory on your main hard drive is not a good idea because that's a spot we usually clean out periodically and throw everything away. Go to where you want it to be saved so you can always get to it. Here's another point. Don't name your file until you get to where you want to save it. If you type in the name at this point and then change the location of the file, ArcView will switch back to the name it wants to give it and if you don't notice, you're going to wonder what you did with that file later!  Here you can see where I have moved to the directory I want to permanently save the file. I've changed the name to one I will recognize and now I will click on OK.  ArcView figures that if you went to the work of sorting the records, you must want to add it as a theme to your view. This next message will appear. If you want to add it to your view, as I did, click yes. Otherwise, just click on no.  I have turned off all of the counties in the US and have turned on my South Carolina counties theme by clicking in the little boxes next to the theme name. See that tiny black spot on the far right? Yup - that's my South Carolina theme! Don't get disappointed. Look at the picture and you'll see a circle with a plus sign in the tool bar labeled "Zoom In." Click on that and then click on your tiny map in the view box. It will start to enlarge. You can also drag a square around it after you've clicked on the Zoom In tool and that will enlarge it, too. There's even another way, but we'll leave that at the moment.  Here I've done two things. I've zoomed in and I've turned back on the rest of the counties. We can now see the South Carolina counties in relation to the other ones in surrounding states.  You can use this same process to take your South Carolina shape file, open up the theme table (attributes) and sort out each of the counties into a separate file. Remember that each record has a lot of fields attached to it that you can use to show all sorts of information about a particular place. The process is essentially the same. In fact, one thing I didn't mention earlier is that you can get more complicated questions put together that allow you to refine your search further in a single query. We call that Boolean logic. If you've gotten to this point, you're also ready to do some creative things with your new project and start to play with some options. I'll show you that on another page. |