Open the map
First, you'll open a web map of Toulouse, France. Then, you'll sign in and save a copy of the map to use in your analysis.
- Open the Toulouse townships and cycling routes web map.
The map has two layers. The Toulouse cycling routes layer shows cycling routes, styled by the type of route. The Toulouse townships layer shows the townships (known in French as communes) that make up the city.
- On the ribbon, click Sign In. Sign in to your ArcGIS organizational account.
Note:
If you don't have an organizational account, see options for software access.
- On the Contents (dark) toolbar, click Save and open and choose Save as.
- In the Save map window, for Title, type Toulouse cycling network analysis.
- Click Save.
A copy of the web map is saved to your account. Map Viewer automatically displays the copy.
Explore the data
Part of your goal is to determine the predominant type of route per township. Before you perform your analysis, you'll explore the data to learn more about the route types.
- If the Legend pane is not already open, on the Contents toolbar, click Legend.
The legend shows the different types of cycling routes.
Based on the map, the most common route types are Piste cyclable ou partagee (a path either reserved for cyclists or shared with motorists), Reseau vert (greenway routes set aside for nonmotorized traffic), and Bande cyclable ou couloir bus (a section of a road marked as a cycling or bus lane).
To use this data in your analysis, you need to know the field that represents route type. To determine this, you'll open the layer's table.
- On the Contents toolbar, click Layers.
The Layers pane appears. It lists the map's layers.
- For Toulouse cycling routes, click the Options button and choose Show table.
The table appears. It shows that there are 2,657 cycling routes in Toulouse, each with several related fields about the name, section, length, and so on.
- Scroll through the table to the carte_velo field.
This field shows the route type. You'll use this field during your analysis.
- Close the table.
Perform the analysis
To determine which townships have the longest and shortest cycling routes, and the predominant route type in each township, you'll run the Summarize Within tool.
This tool overlays a polygon layer (such as your townships layer) with another layer and creates summary statistics for the features in each polygon. It can find the count of features in each polygon, aggregate feature geometry, and group results based on fields, such as the carte_velo field.
- On the Settings (light) toolbar, click Analysis.
- In the Analysis pane, click Tools.
Tools are grouped into categories based on the type of analysis they perform. By default, the Summarize data tools are displayed.
Tip:
To learn more about a tool, point to it.
- Click Summarize Within.
The tool requires several parameters to run. First, you'll choose the features you want to summarize (the cycling routes).
- Under Features to summarize, click Layer.
- In the Select layer window, click Toulouse cycling routes.
The parameter is updated, showing the layer name and its number of features. Next, you'll choose the summary areas, which are the polygons within which the cycling routes will be summarized. In your case, these are the townships, though you could also summarize the routes within a grid of square or hexagon bins.
- Under Summary areas, for Area type, confirm Polygon layer is selected. For Summary polygon layer, click Layer and choose Toulouse townships.
Next, you'll set the summary statistics to be calculated. By default, the tool will calculate the number of routes in each township, and their combined length.
- Under Calculate statistics, confirm Include summarized geometry of features is turned on. For Summarized length units, choose Kilometers.
You also want the tool to group the results by the type of route, so you can determine the predominant type in each township. When you looked at the table, you learned the field for route type is carte_velo.
- For Group by field, choose carte_velo.
Once you change the parameter, contextual parameters appear, including a parameter to calculate minority and majority values and a parameter to calculate the percentage of each route type by total length. Both of these calculations are useful to you.
- Check the Include minority and majority values and Include percentage of summarized feature boxes.
You've set the parameters you need. Lastly, you'll give the output analysis layer a name. Layer names must be unique within an organization, so you'll include a unique identifier.
- Under Result layer, for Output name, type Toulouse cycling network analysis, followed by your name or initials.
You'll also check the tool's credits usage.
- Click Estimate credits.
The tool will use 2.694 credits. The number of credits is based on the number of features that will be analyzed.
- Click Run.
The tool runs.
Tip:
While the tool is running, you can click the History tab at the top of the Summarize Within pane to track its progress.
When the tool finishes, a layer named Toulouse cycling network analysis is added to the map and the Layers pane.
- In the Layers pane, point to Toulouse cycling routes and click the Visibility button.
The layer is hidden on the map. Now, only the analysis layer and the township boundaries are visible. By default, townships with a longer total cycling route length have darker symbols than those with shorter routes.
Review the results
Next, you'll examine the analysis layer's table to better understand the results.
- In the Layers pane, for the Toulouse cycling network analysis layer, click the Options button and choose Show table.
The table has 37 records, each representing a Toulouse township. Many of the fields in this table are also in the Toulouse townships layer's table, but the analysis tool added several new fields. The Summarized Length in Kilometers field shows the combined total length of cycling networks in each township.
- Scroll to the Summarized Length in Kilometers field. Click its options button and choose Sort ascending.
The records are sorted with the lowest value first and the highest value last.
- Check the box for the first record in the table.
The record is selected in the table and on the map. (You may need to pan or zoom the map to see the selected township.) According to the libelle field, this township is called Aigrefeuille. This is the township with the shortest combined cycling network, with a total length of 1.0325 kilometers.
- Click the Clear selection button.
The selection is removed.
Tip:
Alternatively, you can clear the selection by unchecking the selected record.
- Scroll to the bottom of the table and select the last record.
The last record, which is the one with the longest combined cycling network, is the Toulouse township. Its total length is 390.9881 kilometers. This township is also the largest, so it makes sense it would have more cycling routes.
- Clear the selection.
The table includes several other fields created by the tool, including Count of Lines (the total number of cycling routes), Minority carte velo and Majority carte velo (the least and most predominant route type), and Minority carte velo Percent and Majority carte velo Percent (the percentage of all routes that the minority and majority route type represent).
The table also includes an Area in Square Miles or Area in Square Kilometers field, depending on your organization's default unit of measurement settings. This field shows the area of each township. Unsurprisingly, many townships with shorter cycling networks also have smaller areas.
- Close the table.
Style the results
Now that you're familiar with the result data, you'll change the layer's style to best visualize it. The default style indicates which townships have longer and shorter networks, but it doesn't show the predominant type of cycling route.
- In the Layers pane, confirm the Toulouse cycling network analysis layer is selected. On the Settings toolbar, click Styles.
The Styles pane appears. In the Choose attributes section, Summarized Length in Kilometers is listed, indicating that this field is being used to determine the style. You want the style to reflect this field, but you also want it to reflect the predominant route type, which is represented by the Majority carte velo field.
- Under Choose attributes, click Field.
- In the Select fields window, search for Majority carte velo. Check the Majority carte velo box.
- Click Add.
The field is added. The map's style changes.
Each township is represented by a point centroid. The centroid's size indicates the total length of the cycling network and the color indicates the predominant route type.
Only two route types are predominant in any township: Piste cyclable ou partagee (shared or separate cycling routes) and Reseau vert (greenways). The former is more common in the more urbanized central townships, while the latter is more common in the smaller and more rural townships near the edges. This pattern is expected, given that greenways are designed for pedestrians, all-terrain bikes, and road bikes, which are needed in green spaces and rural areas. By contrast, shared cycling and pedestrian paths are more useful in busy urban areas.
Because Reseau vert refers to greenways (vert is French for green), you'll change the color representing this route type to green. To ensure your map is accessible to users who have red-green color blindness, you'll use an effect to transform both symbol colors relative to one another.
- In the Styles pane, click Done.
- On the Settings toolbar, click Effects.
The Effects pane appears. It has options to add effects to your entire map.
- In the Effects pane, click Hue rotate.
- In the Hue rotate window, for Degrees, type 270.
The default symbol colors are shifted 270 degrees along the color wheel, changing red to purple and blue to green.
- Close the Effects pane.
Lastly, you'll change the basemap to one that better complements your data.
- On the Contents toolbar, click Basemap.
- In the list of basemaps, click Light Gray Canvas.
- On the Contents toolbar, click Legend.
Your map indicates which townships have longer and shorter combined cycling networks and which type of cycling route is most common in each township. You've successfully accomplished both of your goals.
- Save the map.
In this tutorial, you used the Summarize Within tool to summarize cycling routes within township boundaries. You calculated the total length of each network and determined the predominant route type in each township.
This analysis can be performed for any city with cycling route data and subdivisions. It can also be performed for other types of data, including point data. For instance, with the relevant data, you could summarize the number of schools or hospitals in each township. Try a summary analysis for your city and see what results you find.
You can find more tutorials in the tutorial gallery.