Hi, welcome to the very first one of the demos for these online modules on GIS
through the Center for Digital Scholarship here at the University of Notre Dame.
Today, I just want to go over a little bit of the very, very basics of ARC GIS, and
I've gone ahead and separated this out from the first real demo that we're going
to do in the second module in raster data, even though we're going to be
manipulating and looking at a couple of different data types this week.
And this is primarily because ARC GIS is a little bit
quirky when it comes to how you add data and
how you begin to really create a map document out of multiple different layers.
So the very first thing that we do when we start working with
ARC GIS is we load up the program, and you can see here, I've already gone ahead and
downloaded both the first and second demonstrations there.
But the first one here is the one we're gonna be I'm working with mostly.
And before we load ARC GIS, let's take a look at what's in here.
What we have is a number of different files,
each one of which is part of an individual layer.
So when we load up the program, we'll only see an individual record for
Indiana places here and this particular satellite image that we see down here.
So even though there are multiple different files all of these
are essentially one layer in the program itself.
So go ahead and start up ARC GIS.
You can either just simply go through your start menu.
I know you can only see part of mine right here but
basically what you're just gonna look for is arc map.
That's the two dimensional visualization program here.
Either by searching for it in the box or by going through the menu into ARC GIS and
finding it.
And once it loads up, and it may take a minute or
two it's a pretty big piece of software here.
What we're gonna end up with is the actual viewer that we'll work with in almost
every one of these modules.
And this is sort of what the load screen should look like.
You have a bunch of standard templates you could deal with,
some of which come with data already in them, like USA and
World here, some of which are just simply page sizes.
For almost every part of this module we're just gonna choose blank map here.
So if you're working off of your own computer you could actually choose,
don't show this dialog in the future.
I'm gonna leave it up just so you're used to seeing what this looks like,
but just go ahead and choose blank map.
So this is the standard ARC GIS file view that we're gonna see.
We have a series of layers over in our Table of Contents here,
we have a bunch of different menus up at the top, and then we have a whole slew of
different tools up here, some of which should look very familiar, New,
Open, Save, Print, others of which may look a little bit different.
We'll work with these a little bit in a second here.
Now the new open and save up here,
we're used to thinking about those as if we would bring in data that way.
Actually what these do is they save the map document itself, and all the map
document is in ARC GIS is links to those data layers and how to display them.
So we don't use these for adding in data.
What we're actually gonna use is this little button right here.
This little sort of square with a diamond with a cross on it.
This is our add data button.
So if you go ahead and click on that, it'll bring up something that, for
you guys, probably looks more like this if you have never loaded the software before.
And that's because of a few different reasons, but ARC GIS has a legacy,
old, old way of computers being organized view of the file system on a computer.
So before we can begin to look in an individual folder we have to
first sort of map to it.
We have to tell it where that location is and
then that will be a preset kind of bookmark that we can go back to, and
we do that by clicking on this button here in this connect to folder.
I would encourage you guys to store this someplace where you can get to it.
Store all of your GIS data in the same spot and
name it in an intuitive and intentional way.
So I have mine on my N drive here.
In GIS, and that's the same folder that I showed before where I had my demo 1 and
my demo 2.
I'm gonna choose to just to map to the GIS folder, that way I can get to all of them
without having to re-map to individual sub-folders there, so
just go ahead and hit OK.
Now then it should look like this for you and now you can go into Demo One, and
this is showing those two layers that I talked about before.
In this week's lecture or this module's lecture we talked a little bit about
the difference between raster and vector data.
And ARC GIS is actually showing us what types of data we have with these little
icons right here.
This thing that looks like a grid, the individual pixels in there.
This is raster data.
These things that look like individual points or
geometry, some of them look like lines, some of them look like polygons
depending on what type of vector data they are is right here.
So we are going to go ahead and add both of these in so
you can either click outside of it and drag up you could hold down shift or
control and click on both of them but try to add them both in at the same time.
Go ahead and hit Add.
It'll think for a minute and then it's gonna load up a vector data
that's all of the populated places in the state of Indiana and
a raster layer that's a satellite image for this Northern Indiana section.
So just a little bit on navigating in ARC GIS we have all of the tools up here
to sort of navigate, some of which should look pretty familiar.
We have zoom in, zoom out, pan, which will let us click and drag around.
This full extent will zoom us all the way back all of the way out.
These guys are fixed zooms in or fix zoom out.
You can see the scale changing up there.
This let us go back to whatever previous extent was in go back and forth that way.
We'll get to all of these other tools later on in the modules.
One other thing you'll see me doing this relatively quickly throughout here,
your mouse button.
I can't obviously show this in a screen cast, but
if you have a three button mouse you're working with.
And I encourage you to not work off a trackpad on a laptop when you do GIS,
because these tools will really save you a lot of time.
The center wheel will let you zoom in and out.
So go ahead and try that if you have a three button mouse.
I find what zooms you in and what zooms you out to be pretty counterintuitive.
Your results may vary, but go ahead and experiment around with that a little bit.
And then if you hold down that center mouse button, that part of the wheel,
it'll let you pan it, and this will work in pretty much any tool in the software.
So it's a pretty useful way to begin to quickly navigate around.
A few other things that we see up here, we have our layers and our table of contents.
If I change, if I drag these around,
you see that the points disappear behind the raster image.
If I wanted just to see the extent of the raster image I could always right click
on it and go down to zoom to layer.
Same thing with the other one if I wanna go all the way out, and
then I could use my previous extent button to go back to where I was before.
So just I encourage you guys to just sort of play around a little bit,
explore at this point.
One other tool that might be useful for you is this Identify tool.
If you click on this, you see your mouse has a little eye on it.
If you can hit one of those points.
It'll give you a little pop up window that tells you that that's Roble Woods.
The county it’s in,
you'd see it in a little information in there out of that vector file.
If you miss and hit the raster image.
It's just gonna give you pixel values for that particular spot, and
this will all become clear, what this means will become clear quite
a bit later on, actually next week, or the next module.
So just experiment around with it a little bit.
Get a feel for how to navigate.
Get a feel for how to manipulate and add data into ARC GIS.
There's no assignment for this particular demo.
This is just to get you started with things, but
one last idea here is if you want to save this document you can.
What you would end up doing if you hit Save, you probably want to stick it in
the same place that you're dealing with the other data.
All this is doing is saving what layers are added in, not the individual,
not the data behind those layers, but what layers and how they are being
displayed and the order and the scale, the zoom and all these things.
So it's a good way to save a map document if you wanted to be able to load it back
up with all of the data in the same spot, or if you wanted to create kind of
an important visualization, something we'll get to later on in the semester, and
then be able to reacquire that pretty easily.
So that’s really all I wanted to show you guys today.
Please do experiment around a little bit, and
feel free to email me with any questions or any comments on how this is working.