arcgis 9 ch 11 edited 06/14/05 1 land use analysis an important aspect of any gis is the use of...

ArcGIS 9 ch 11Edited 06/14/05

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Land Use Analysis

An important aspect of any GIS is the use of analysis.

Analysis helps us to say something meaningful about the work that we have done, and it makes the work uniquely

ours. Paper maps have been made for years, but it’s your work that creates a unique GIS.

In this section, we are going to work through some analysis of your school and the way that the land is used on your campus. For this, we will need both ArcGIS and Excel.


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Land Use on Campus

Your final task is to create a pie chart to show the relative amount of land on campus dedicated to various functions.


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1. For this exercise you will need to open Microsoft’s Excel spreadsheet application in addition to your workspace in ArcGIS.

2. Create a table in Excel resembling the one above. Now open your ArcGIS Project.

3. You can minimize your Excel spreadsheet while you go back to work in ArcGIS, if you wish.

Function Area Area Percentage

Athletic

Academic

Administration

Parking Lot

Assembly/Bleacher

Performance

Other


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4. Right-click on the word parking-lot and open attribute table.

5. Click on the Options button and select “Add Field.”


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6. Type “area” in the name box, then select “Double” as the type. Click OK


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8. Right click on the area field and choose “Calculate Values.”

7. Go to the Editor button and Start Editing. Select the location of the shapefiles from your GPS and click OK.


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9. Our school features have been created using latitude and longitude coordinates, which we measure in degrees. We don’t want our “area” measurement to be in “square degrees” – no one would know what you are talking about!! The script above will calculate area based upon the coordinate system of our data frame, which is measured in meters. Click this link to open a text version of the script; copy the script and paste it in the Pre-Logic VBA Script code box.


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10. In the “area =“ field, type “dArea”.This tells ArcGIS which variable inthe script will contain the final areacalculation. Click OK.

11. The area measurement, in square meters, will appear in the area column. Repeat this process for all of your polygon features.


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12. The next step will sum up the area for each building function. Open the attribute table for Buildings

13. Right-click on Function and select Summarize….


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14. Select Function as the field to summarize and check Sum under area. Click OK.

15. Click Yes to add to the map.


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16. In your legend you should see something called Sum_output with a number. Right-click on it and select Open.

17. Notice that all of your academic area has been summed, as well as athletic area, etc.


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18. Sum up all of your categories of your polygon features as in this example.

Total athletic area = Sum of athletic buildings + Sum of athletic fields.

Total athletic area = 1861.3174 + (10287.232336 + 2132.350417 + 5026.44319)

Total athletic area = 1861.3173 + 19307.343343

Total athletic area = 21168.66743

Place the total in the appropriate category in the Excel spread sheet.


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19. After entering your area sums in the Excel table, calculate the total area of all categories.

Example:

Athletic Area Percentage = (21168.66074 / 36523.60615) * 100= 0.579588463 * 100= 58%

20. For the Area Percentage, divide the category area by the total.


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21. Highlight all of the cells of your table other than “Total”.

22. Click on the Chart Wizard button.


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23. Select Pie for your Chart type. Click “Next”.

24. Click “Next”.


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25. You can type in a new title here if you like. After changing your title, click Next.

26. You may select either to have the chart in a new worksheet, or in the same sheet as your table. Click finish.


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27. Your pie chart will appear in your worksheet. Double-click on the “pie.”

Land Use at Center High School

Athletic

Academic

Administration

Parking Lot

Assembly/Bleacher

Performance

Other

28. Select the Data Labels tab and check Percentage.


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Your final step is getting your work into presentation form. Chapter 12 will help you with creating an interesting map.

Land Use at Center High School

58%

12%

1%

7%

1%

0%

21% Athletic

Academic

Administration

Parking Lot

Assembly/Bleacher

Performance

Other

arcgis 9 ch 11 edited 06/14/05 1 land use analysis an important aspect of any gis is the use of...

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