[MUSIC] Hello everyone and welcome back. In this lesson we're going to do a quick review of how to use geoprocessing tools since they are so important for working in GIS. They aren't just an ArcGIS concept, QGIS uses, them many GIS systems have this concept of some kind of tool that does Arc geoprocessing work. For those of you joining us from the last class, we used a number of geoprocessing tools in that class. Most importantly, we used the spatial join tool, but you also used a handful of others during the projects in the class. For this lecture, I just want to reintroduce them so that you have them in mind for the rest of this course and the rest of the courses in the specialization, especially for those of you who maybe didn't take the first course. It's really important that you understand geoprocessing tools. So, let's recall geoprocessing tools come from ArcToolbox and when we chain them together, we get complex workflows that process our data and help us answer our geospatial questions. Behind the scenes, many of our interface features like, Select By Attributes and Select By Location, they're actually geoprocessing tools. They're running the same code. But how we actually access geoprocessing tools is in ArcToolbox, and I have that up here. But if we didn't, we could click this button to bring it up, or go to the geoprocessing menu and click ArcToolbox. If we knew something about the geoprocessing tool we are interested in but couldn't remember where it is in the tool box, we could search for tools. So in this case though, I know that I just want to re project this data. It's in kind of a non standard projection for this area. This is a part of northern California here, and it's a soils layer. And the rest of my data is in a UTM projection, UTM zone ten north, and I want to make this data be in that same projection so that it's not recalculating the projection on the fly and that it always aligns correctly with my data when working with other tools. So, I'm going to use the project tool, it'll look like project to some of you, but it's the project tool, to reproject this data from the current projection it's in, to a new projection. So, I'll scroll down here, and that's in data management, and it's in the projection and transformations tool set. So we have tool boxes, tool sets, and then tools, with the little hammers, and the project tool is the one that I'm interested in. So if I double click it, I can bring it up, and it gives me a number of parameters. First, the required parameters have this little green dot next to them, so I need to fill those in, but it might help me with some of those as I fill in other parts of this. I can also see the tool help on the right side, that helps explain what different parts of this tool do. And they're context sensitive so if I click into something else, they'll change to tell me what that input or output item does. If you don't have it it's because this is hidden right now. So if I click Hide Help, yours might look like this. So click Show Help. Make sure that's always blown out, it's really useful. And then if I wanted to get the full help documentation, I could click Tool Help and bring it up. In the meantime, I have three ways of working with this control here. So I have a full tool here, and it's made up of a subset of controls. And I need to fill this in before I can run the tool, because it needs all this information so that it can give me the output that I'm looking for. In this case, again, it's that I want to project spatial data from one coordinate system to another. That's the goal and I need to provide an input data set, or feature class, and output data set, or feature class, and that output coordinate system. The coordinate system we want it to be in when it's done. So, to do this, I can add this layer to my control here three different ways. I can select it by the down arrow and click it here and it'll fill some things in for me. It'll look up its current coordinate system. It'll give me an output file in my existing default geo database for the map document. And then I still don't have output coordinate system. I need to select that manually. I can also, instead of selecting it from the dropdown, I can just drag and drop it from my table of contents here and it will fill in the same information, or if I wanted to I could use the browse tool here to find it on my hard drive. So those are three ways of working with controls for input data sets. Now I need to select the output coordinate system, I said before that I wanted to use the UTM coordinate system so I'm going to click the coordinate system selection here. And it brings up the spatial reference properties box and let's just narrow it down and I'm going to type UTM here in the search box and hit enter and it'll search and found 967, but if I expand this, I see that the selection has narrowed significantly, and I can select UTM. And yours will be different than this because you're in a different part of the world than me. But in my case, I'm going to just select NAD 1983, I know that I am in UTM zone 10 north. If you aren't sure of which UTM zone you are in, you can look it up online just search Google UTM zones and you will see a grid of the world come up. Look on Wikipedia page or somewhere else, that will help you decided what UTM zone you are in. I click OK. It fills in the output coordinate system code here and then right now I'm ready to run the tool, but let's look at a few other things. First, Environment Settings. These help you constrain your analysis further and they're common across geoprocessing tools. If you want to know more about them, look at the lecture in the last class about them. But the environment settings style looks a little like this. We have a lot of options here, and we can expand these field sets in order to see more options for our geo processing tool. I'm not going to set any of these in this case. And the last thing here is that there's a new feature in ArcGIS 10.3. When you re-project data, it's moving all the coordinates to their corresponding location in the new projected coordinate system. And it's not trying to physically move them on the Earth, but it needs to rewrite the coordinates so that they're valid in the new reference system. Depending upon which coordinate systems you're changing between, this can introduce distortion in your data, either in the shape or the area or things like that. So you can click this new box that says Preserve Shape, and what ArcJS will do Is it's going to add extra vertices to the output lines or polygons in order to keep the shape the same. Now, in this case, I don't want to do that. I just want to keep the original data as pure as possible and I'm going to leave that unchecked. But know that that's an option, it's great probably for cartographic uses and a few other use cases. And now I can click OK to run the geoprocessing tool, and it comes up at the bottom here and says it's running. I can also see that it's running if I go to the geo processing results pane, on the left side here. And I can see that it's running and it gives me messages, and if it has an error it'll show me, and if it succeeds it'll show the hammer again and what I will also get is the layer added to my table of contents. Now, in this case, it doesn't look much different from what we've been looking at before. It's writing it out directly on top of the data. And that should be expected, take a moment and think about why. Okay, so in this case, we have data in the new projections. I can verify that by going to Properties and seeing Projected Coordinate System USA_Continguous_Albers_Equals_Area_Conic_- USGS. And if I right click on my new layer here, I go to properties and see that it's now at 1983_UTM_Zone_10 North, great. So why are they showing up exactly the same? Well, first they encode for the same locations, right? So we expect that they should show up in the same way on the map. Second, the data frame has its own coordinates system, which was set when I added the first layer to this map. So it matches the first layer we had. And if I am displaying new layers in this data frame, it's going to reproject on the fly any data layers In the data frame so that it matches its own projection. It doesn't modify the new layer's projection on its stored version on my disk, but it does modify the version that's represented on the screen here so that they can be displayed In the same data frame. If they're not in the same projection, it's hard to compare coordinates, and it can't line them up. So it needs to re-project it in the background, so that we can display on the screen. Now, there is a way that we can also see what we just did. And, to do that, I'm going to add a new data frame. Go to Insert, Data Frame. And it's an empty data frame, but I'm going to copy the new layer over there. And now it has it's own default projection, which is this layer's default projection. And I can see that it's kind of aligned vertically over here a little more and if I go to this other dataframe and click activate, and zoom back out to the full extent, we have a different orientation here, right, if I switch back and forth between them. And those are properties of the projection that we're seeing in action here. The data is still the same, but it's being displayed differently because the projection has different orientation information in it. So we can see that the project tool did transform our data, it's subtle in this case but it did do a transformation on it. Some tools aren't as subtle like the spatial join tool where you get new data attached to your data, and the intersect and the clip tool, they modify your data, your features in place too. Throughout this class, we're going to start using these geoprocessing tools more. I'll introduce more of them to you, starting with the intersect tool next. And then, what we're going to start doing is trying to introduce algorithms, where we chain these things together into workflows for you, because that's the core thing you need to take away from this entire specialization. Is how to use geoprocessing in entire workflow start to finish thing. I have some data as an input and I need to get an answer in what set of geoprocessing is going to get me to that answer. So we're going to start building you up to that kind of thinking in this course. Okay, so that's it for this lecture. In this lecture we reviewed what a geoprocessing tool is, how to use it, how to work with it, some of the controls it has, and how to use the geoprocessing results pane. As I said, next lecture we'll work with the intersect tool. See you there.
