Understanding GIS. David Smith
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Название: Understanding GIS

Автор: David Smith

Издательство: Ingram

Жанр: Программы

Серия: Understanding GIS

isbn: 9781589485273

isbn:

СКАЧАТЬ follow the river to its source, marking good areas for a park along the way. A really good area would have these properties:

      •high population density (dark red),

      •low median household income (small green dot),

      •no existing park nearby, and

      •close to the river.

      3)Pan slowly north.

      Less than a mile north of the city limits, on the east side of the river, are a couple of tracts—one dark red and one medium red—with small green dots. They’re pretty close to the river, and even though there are some parks in the general vicinity, it’s probably worth marking the area as a potential park.

      To mark the area, you’ll use a feature of ArcGIS Pro called Map Notes. Map Notes are layer templates that create point, line, and polygon feature classes in your Home database with predefined symbols for feature creation and editing.

      4)On the Insert tab, in the Layer Templates group, click the Bright Map Notes button.

      Clicking the button adds a new group layer to your Contents pane named Bright Map Notes.

      5)Expand the Bright Map Notes layer to see that it contains point, line, and polygon layers.

      6)Expand the three layers to see their predefined symbols.

      7)Collapse the Bright Map Notes group by clicking the little arrow to the left of the check box.

      8)In the Catalog pane, browse and expand your home database in the Databases group. Notice that three new feature classes have been added to the geodatabase. These classes are the data sources for the Map Notes layers that were added to the map.

       Create a new feature

      You will now create a new feature in the feature class.

      1)Go to the Edit ribbon.

      2)Confirm that Snapping is turned off. It should have a white background, not blue.

      3)In the Features group, click the Create button .

      This button opens the Create Features pane on the right of the map. This pane allows you to draw new features in any of the layers marked as editable in the map. By default, all layers are editable, so you will change that so that you don’t accidentally add new rivers, parks, census tracts, and so on.

      4)In the Contents pane, click the List By Editing button above the layer list.

      This list now displays all the layers with a check box next to each one to define whether they are editable or not.

      5)Click to clear all but the Bright Map Notes layers (you will probably have to expand the group layer to confirm that they are checked).

      Notice that as you click to clear the other layers, the Create Features pane to the right of the map changes to show only those features that are editable.

      6)Switch back to the List by Drawing Order view by clicking the button at the top of the Contents pane.

      7)Add a purple star point near the areas of interest by clicking the Star 4 icon from the Create Feature pane on the right side of the application and then clicking the spot on the map.

       To stop adding stars, click the Explore button on the Map tab. To delete unwanted stars, click the Undo button.

       Continue searching for park areas

      You’ll keep following the river and looking for likely places for a park.

      1)Click the Explore button on the Map tab and pan north.

      A little farther north, again on the east side of the river, is a medium-density, lower-income area with just one park (Pecan Playground) in the general vicinity. You’d prefer a high-density neighborhood, but since you don’t yet have specific criteria for your analysis, you want to be inclusive rather than exclusive in your assessments. It’s up to you whether to mark this area or not—all that really matters is that you start to gain a sense of the study area.

      2)Add another purple star in this area by going back to the Edit tab and clicking the Star 4 icon.

      The area opposite Dodger Stadium, on the east side of the river, is medium density, lower income, and park poor, which makes it rich with possibility for a new park site.

      3)Add another purple star in this area.

      4)Mark any other areas that seem promising to you.

      As you navigate around Griffith Park, remember that the yellow line marks the city limits. The areas north and east of the park aren’t part of Los Angeles and shouldn’t be considered. Once you get around this park, you may find fewer likely areas. But remember, there’s no right or wrong answer for this exercise.

      5)When you’re finished marking promising locations, zoom to the layer Bright – Point Notes.

      6)Save your edits by clicking the Save button in the Manage Edits group.

      7)When prompted to save all Edits, click Yes.

      8)Close the Create Features pane.

      9)Return to the Explore tool on the Map tab to stop editing.

      10)Close the Lesson1b map and any open tables.

      11)Save your project.

      12)Continue to the next lesson or close ArcGIS Pro. Save your changes if prompted.

      Now that you’ve explored the study area around the Los Angeles River, you will begin to list the data requirements for the project and begin previewing the data that meets your project needs. This data can also help you reframe your СКАЧАТЬ