Obtaining the Tutorial Data

Before beginning the tutorial, you will copy all of the required tutorial data onto your Desktop. Option 1 is best if you are completing this tutorial in one of our short courses or from the GIS/Data Center and Option 2 is best if you are completing the tutorial from your own computer.

OPTION 1: Accessing tutorial data from Fondren Library using the gistrain profile

If you are completing this tutorial from a public computer in Fondren Library and are logged on using the gistrain profile, follow the instructions below:

1. On the Desktop, double-click the Computer icon > gisdata (\\file-rnas.rice.edu) (R:) > Short_Courses  >  Introduction_to_Geoprocessing.
2. To create a personal copy of the tutorial data, drag the Geoprocessing folder onto the Desktop.
3. Close all windows.

OPTION 2: Accessing tutorial data online using a personal computer

If you are completing this tutorial from a personal computer, you will need to download the tutorial data online by following the instructions below:

1. Click Geoprocessing.zip above to download the tutorial data.
2. Open the Downloads folder.
3. Right-click Geoprocessing.zip and select Extract All....
4. In the 'Extract Compressed (Zipped) Folders' window, accept the default location into the Downloads folder and click Extract.
5. Drag the unzipped Geoprocessing folder onto your Desktop.
6. Close all windows.

Geoprocessing in ArcGIS Pro

Opening an Existing Project

1. On the Desktop, double-click the Geoprocessing folder.
2. Double-click the Geoprocessing.aprx project file to open the project in ArcGIS Pro.

Running Geoprocessing Tools

Geoprocessing tools are used to update and analyze data based on a particular criteria. The majority of geoprocessing tools generate a new feature class that differs from the input feature class(s) either in feature geometry or attributes or both.

Merge

The first set of data you will be working with contains the Houston Police Department (HPD) beat boundaries. Though it has been modified for the purposes of this tutorial, the original data was obtained from the City of Houston GIS Database webpage, which is no longer available, but the original data can be obtained from the GIS/Data Center data collection.

1. In the Catalog pane on the right, expand the Databases folder.
2. Expand the Geoprocessing.gdb geodatabase.
3. Right-click the HPDBeats_North feature class and select Add To New Map.
4. Right-click the HPDBeats_South feature class and select Add To Current Map.

Notice that the police beats in the City of Houston have been divided into two separate feature classes covering the northern and southern portions of the city respectively. You will now examine their attribute tables.

1. In the Contents pane, right-click the HPDBeats_North layer and select Attribute Table.

Notice that you are provided with both the beat number and the district number for each police beat, and there are 55 beats in the north layer.

1. In the Contents pane, right-click the HPDBeats_South layer and select Attribute Table.

Notice that the south layer contains 62 beats with the same data fields.

1. Close all table views.

At this point, you wish to combine the north and south police beats into a single layer. You will do so using a geoprocessing tool.

1. On the ribbon, click the Analysis tab.
2. Within the first Geoprocessing group, click the Tools button.

Notice that the Geoprocessing pane has opened on the right as a new tab on top of the Contents pane. Typically, you would use the 'Find Tools' search box to search for the name of the tool you'd like to use, but, at times, especially when learning the software, it can be helpful to view the full hierarchy of all the tools available, because you will often discover related and helpful tools that you didn't know existed and wouldn't know to search for. You might also completely forget the name of a tool, but be able to locate it based on the hierarchy. For these reasons, we will be manually navigating the toolboxes for this tutorial. The more typical workflow of searching directly for a specific tool will be covered briefly at the end of the tutorial.

1. At the top of the Geoproccessing pane, click the Toolboxes tab.
2. Click the Data Management Tools toolbox > General toolset > Merge tool.
3. In the upper right corner of the ‘Merge’ tool, hover over the help button.

Read the Merge pane help and review the sample illustration. Notice that this tool merges two like datasets covering different geographic extents together into a single dataset. Clicking on the help button will open the full tool documentation in your default web browser.

1. For ‘Input Datasets’, use the drop-down menu to select the HPDBeats_South layer.

After selecting the HPDBeats_South layer, another drop-down menu appears.

1. Use the second 'Input Datasets' drop-down menu to select the HPDBeats_North layer.

Notice that the when you hover over the 'Output Dataset' field, Output Dataset defaults to your default geodatabase (C:\Users\gistrain\Desktop\Geoprocessing\Geoprocessing.gdb).

1. For ‘Output Dataset’, rename only the feature class portion of the file path from HPDBeats_South_Merge or HPDBeats_North_Merge to “HPDBeats".
2.  Ensure that your Merge tool Parameters tab appears as shown below and click Run.

When the tool is finished running, you will see a message at the bottom of the Geoprocessing pane with the name of the tool. A green checkmark indicates that the tool ran successfully. You may also see a yellow warning icon or a red X if the tool has warnings or fails.

1. In the Contents pane, right-click the HPDBeats layer and select Attribute Table.

Scroll down the attribute table and notice that the attributes for both the north and south beats feature classes were preserved and combined into a single table with 117 beats. Since you now have all the beats contained in a single layer, you no longer need the separate layers for the north and south beats.

1. In the Contents pane, right-click the HPDBeats_North layer and select Remove.
2. In the Contents pane, right-click the HPDBeats_South layer and select Remove.
3. Above the ribbon, on the Quick Access toolbar, click the Save button.
   
   

Dissolve

As explained in the tutorial introduction, the collaboration with the schools is going to be based on the police districts, not the police beats. At this point, your HPD layer only displays the police beat boundaries, but its attribute table does tell you the district number corresponding to each beat.

1. Scroll down the HPDBeats attribute table while observing the values in the District field.

Notice that each district contains many beats. You will now dissolve the police beats based on this District field so that all beat boundaries within a single district will be dissolved into a single district boundary.

1. Close the HPDBeats table view.
2. At the top of the Geoprocessing pane, click the Back button.
3. In the Geoprocessing pane within the already expanded Data Management Tools toolbox, click the Generalization toolset > Dissolve tool.
4. In the upper right corner of the ‘Merge’ tool, hover over the help button.

Read the Dissolve help and review the sample illustration. Notice that this tool dissolves boundaries based on common field values. In this case, you will dissolve the police beat boundaries based on common district values, resulting in a file showing only the larger district boundaries.

1. For ‘Input Features’, use the drop-down menu to select the HPDBeats layer.
2. For ‘Output Feature Class’, rename the feature class from HPD_Beats_Dissolve to “HPDDistricts”.
3. For ‘Dissolve_Field(s)’, use the drop-down menu to select the District field, since this is the field containing the common district values you wish to dissolve on.
4. Ensure that your Dissolve tool Parameters tab appears below, and click Run.
5. In the Contents pane, toggle the new HPDDistricts layer off and on to understand the result of the Dissolve tool.
6. In the Contents pane, right-click the HPDDistricts layer and select Attribute Table.

Notice that only the dissolve field, in this case the District field, was preserved. Because multiple beats were dissolved into each district, it is not possible to retain all of the attributes of each separate beat.

1. Close the HPDDistricts attribute table.

Since you only need to use the police districts, you may now remove the police beats layer.

1. In the Contents pane, right-click the HPDBeats layer and select Remove.
2. Above the ribbon, on the Quick Access toolbar, click the Save button.

Clip

Now you will examine the school district boundaries. Though it has been modified for the purposes of this tutorial, the original data can also be obtained online from the City of Houston GIS Database webpage at http://cohgis.houstontx.gov/cohgis2010/index.html[g2]  within the administrative boundary dataset.

1. At the bottom of the Geoprocessing pane, click the Catalog tab.
2. Within the Geoprocessing geodatabase, right-click the HISD feature class and select Add To Current Map.

Notice that this feature class displays the boundary of the Houston Independent School District, which can be considered the study area boundary for this project. All of the other data layers you bring into your map document can be clipped to the study area boundary to reduce the size of the files you are working with, which will eliminate visual clutter and allow various processes to run more quickly. First, you will clip the police districts to the study area boundary.

1. At the bottom of the Catalog pane, click the Geoprocessing tab.
2. At the top of the Geoprocessing pane, click the Back button.
3. Click the Data Management Tools toolbox to collapse it.
4. Click the Analysis Tools toolbox > Extract toolset > Clip tool.

Read the Clip pane help and review the sample illustration. Notice that this tool clips one dataset to the extent, or shape, of another dataset.

1. For ‘Input Features’, use the drop-down menu to select the HPDDistricts layer.
2. For ‘Clip Features’, use the drop-down menu to select the HISD layer.
3. For ‘Output Feature Class’, rename the feature class from HPDDistricts_Clip to “HPDDistricts_HISD” and click Run.

Notice that the resulting HPDDistricts_HISD layer maintains the police district boundaries, but limits the extent of the districts to the extent of the HISD boundary. You no long need the full police districts layer and may remove it.

1. In the Contents pane, right-click the HPDDistricts layer and select Remove.

You will now work with a dataset containing the locations of all violent crimes (including murder, rape, aggravated assault, and robbery) occurring in 2010, as reported by HPD. Though the data has been pre-processed for this tutorial, the original data tables can be obtained online from the Houston Police Department Crime Statistics webpage at http://www.houstontx.gov/police/cs/stats2.htm.

1. On the right side of the screen, close the Geoprocessing pane.
2. In the Catalog pane, drag the HPDCrime2010 feature class into the Map Display.

You will now clip the crime layer to the study area boundary to reduce the size of the dataset.

1. In the Analysis tab, click the Analysis Tools toolbox > Extract toolset > Clip tool.
2. For ‘Input Features’, use the drop-down menu to select the HPDCrime2010 layer.
3. For ‘Clip Features’, use the drop-down menu to select the HISD layer.
4. For ‘Output Feature Class’, rename the feature class from HPDCrime2010_Clip to “HPDCrime2010_HISD” and click Run.
5. In the Contents pane, right-click the HISDCrime2010_HISD layer and select Attribute Table.

Notice that you are provided with the date and hour of the crime, the type of offense, the premise code, the number of offenses, and the approximate address. Since crimes are actually only reported by the block address range, not the exact street address, this address represents the midpoint of the block on which the crime was reported.

1. Close the HISDCrime2010_HISD table view.
2. In the Contents pane, right-click the HPDCrime2010 layer and select Remove.
3. In the Contents pane, uncheck the HPDCrime2010_HISD and HISD layers, so that only the HPDDistricts_HISD layer is visible.
4. Above the ribbon, on the Quick Access toolbar, click the Save button.

Buffer

The final dataset you will work with contains the locations of all the elementary schools in HISD. Though it has been modified for the purposes of this tutorial, the original data can be obtained online from the Texas Education Agency School District Locator Data Download webpage at http://schoolsdata2-tea-texas.opendata.arcgis.com/

1. At the bottom of the Geoprocessing pane, click the Catalog tab.
2. In the Catalog pane, right-click the HISDElemSchools feature class and select Add To Current Map.
3. In the Contents pane, right-click the HISDElemSchools layer and select Attribute Table.

Notice that you are provided with the elementary school name, address, and grade range.

1. Close the HISDElemSchools table view.

Now you will create a one-half mile buffer around each school, so that you will later be able to count the number of violent crimes occurring in 2010 within each buffer.

1. In the Geoprocessing pane, click the Analysis Tools toolbox > Proximity toolset > Buffer tool.
2. For ‘Input Features’, use the drop-down menu to select the HISDElemSchools layer.
3. For ‘Output Feature Class’, rename the feature class from HISDElemSchols_Buffer to “HISDElemSchools_HalfMileBuffer”.
4. For ‘Distance [value or field]’, type “0.5” and use the unit drop-down box to select Miles.
5. Click Run.
6. In the Contents pane, right-click the HISDElemSchools_HalfMileBuffer layer and select Attribute Table.

Notice that all three fields contained in the original schools point layer (school name, address, and grade range) have been preserved. In addition, a new field has been added stating the radius of the buffer in feet.

1. Close the HISDElemSchools_HalfMileBufferattribute table.
2. Above the ribbon, on the Quick Access toolbar, click the Save button.
3. In the Contents pane, uncheck the HISDElemSchools layer and check the HPDCrime2010_HISD layer.

Spatial Join (Points to Polygons)

At this point, you can see all of the violent crime locations along with the half-mile school buffers, but much of the map is so densely covered with overlapping points that it becomes difficult to tell exactly how many points there are and to see the underlying school buffers. In addition, while you can see the spatial distribution of the points, you are not provided with any sort of useful summary of the data. Performing a spatial join will allow you to discover exactly how many violent crimes occurred within a half mile of each school in 2010.

The goal of performing a spatial join is to add a numeric field to the end of the school buffer attribute table that tells you how many crime points are contained within each school buffer.

1. In the Contents pane, right-click the HISDElemSchools_HalfMileBuffer layer and select Joins and Relates > Spatial Join.
2. For ‘Join Features’, use the drop-down box to select the HPDCrime2010_HISD layer.
3. For ‘Merge Rule,’ use he drop-down menu to select Count.
4. For ‘Output Feature Class,’ rename the feature class from Join_Output to “HISDElemSchools_HalfMileBuffer_WithCrimeStats".
5. Ensure that your Spatial Join tool Parameters tab appears as shown below and click Run.

The new layer should appear at the top of your Contents pane. 

1. Right-click the HISDElemSchools_HalfMileBuffer_WithCrimeStats layer and selectAttribute Table.

Notice the newly added Join_Count field.  This field tells you how many crime points are contained within each school buffer.

1. Close the HISDElemSchools_HalfMileBuffer_WithCrimeStats table view.

Since the newly joined buffer layer contains all of the same information as the original buffer layer, plus the new Join_Count and Sum fields, you no longer need the original buffer layer. Since your crime data has now3 been summarized, you no longer need the original crime points either.

1. In the Contents pane, right-click the HISDElemSchools_HalfMileBuffer layer and selectRemove.
2. In the Contents pane, right-click the HPDCrime2010_HISD layer and selectRemove.
3. Right-click the HISDElemSchools_HalfMileBuffer_WithCrimeStats layer andselectSymbology.

The Symbology pane...

1. For ‘Primary symbology', use the drop-down menu to click Graduated Colors.
2. For ‘Field:’, use the drop-down menu to select the Join_Count field.
3. In the ‘Color Scheme:’ box, leave the default selection of Graduated colors.
4. Under the Upper Value column, click the first upper value box 27.000000 and type “25” and press Enter to move to the next range.
5. Type “50” and press Enter.
6. Type 100” and press Enter.
7. Type 150” and press Enter.
8. Type 200” and press Enter.

You can now easily tell which schools have the largest number of violent crimes occurring within a half mile radius.

1. Above the ribbon, on the Quick Access toolbar, click the Save button.

Spatial Join (Polygons to Points)

You now have an attribute table that tells you the number of violent crimes that occurred within one year within a half mile of each school, but you would also like to have a table that tells you in which police district each elementary school lies. To create this table, you will perform another spatial join to add the attributes of the police beat to the back of each school that lies inside it.

1. In the Contents pane, uncheck the HISDElemSchools_HalfMileBuffer_WithCrimeStats layer and check the HISDElemSchools layer.

At this point, only the elementary school point locations and the police district boundaries should be visible.

1. In the Contents pane, right-click the HISDElemSchools layer and select Attribute Table.
2. Scroll to the right and browse through all of the attributes.

Remember that, at this point, the attribute table only contains the school name, address, and grade range.

1. Close the attribute table.
2. In the Contents pane, right-click the HISDElemSchools layer and select Joins and Relates > Spatial Join.
3. For ‘Join Features’, use the drop-down box to select the HPDDistricts_HISD layer.
4. For ‘Merge Rule,’ click the drop down arrow to select Join.
5. For ‘Output Feature Class,’ rename the feature class from “HISDElemSchools_SpatialJoin” to “HISDElemSchools_WithHPDDistricts.”
6. Click Run.

The new layer should appear at the top of your Contents pane. 

1. Right-click the HISDElemSchools_WithHPDDistricts layer and select Attribute Table.
2. Scroll to the right and notice the newly added District field. The District field tells you which police district each school falls within.

Notice that the five schools do not have a district assigned to them. That is because those schools fall within HISD, but do not fall within the City of Houston police jurisdiction.

1. Close the HISDElemSchools_WithHPDDistricts table view.

Searching for Tools

In this tutorial, you navigated to various geoprocessing tools directly through the Toolbox; however, it is likely that when you go to work on your own, you may not remember exactly where all those tools are located.  As long as you can remember the name of the tool or what it does, you can find it using the search function.

1. On the Analysis tab, click the Tools button.
2. At the top of the Geoprocessing pane, in the Search box, type “Buffer” and press Enter.
3. Click on the first tool that says Buffer (Analysis Tools) to open the tool.