Process Summary Details
Once again, I detailed my steps because I got stuck, this time at the Union section. I had made 2 mistakes that were not allowing the proper attributes to show up. I found detailing the steps helped me retrace and start again with a better understanding of what I was doing at each section and then I could duplicate it without any problems.
Once again, I detailed my steps because I got stuck, this time at the Union section. I had made 2 mistakes that were not allowing the proper attributes to show up. I found detailing the steps helped me retrace and start again with a better understanding of what I was doing at each section and then I could duplicate it without any problems.
1)
Step
1: Creating a distance buffer:
-
Added
‘roads’ data layer
-
In
ArcToolbox, under Analysis and Proximity, chose Buffer (A)
-
Parameters
for buffer: ‘linear distance of 300 meters’; ‘dissolve all’ buffer borders
2)
Named
output feature class “Roads_Buffer300m”
3)
S:\Vector2\roads_buffe300mr
-
Turned
off Roads and Road Buffer layers
4)
Step
2: Creating a Variable Distance Buffer”
1.
Added
‘water’ shapefile layer
2.
In
‘attribute table’: Add field of type ‘Short Integer’ and name “buffdist”
3.
‘Select
by Attributes” for ‘lakes’
4.
In
‘buffdist’ column, right-clicked to select ‘field calculator’ and assigned as
“150”
5.
‘Switched
Selection’ to ‘River’ feature and assigned “500” in ‘field calculator’
6.
‘Clear
Selection’
7.
In
ArcToolbox, selected ‘buffer tool’ and created “Water_Buffer_variable” layer
5)
S:\Vector2\water_buffer_variable
1.
Moved
Water layer on top of Buffer layer
2.
Turned
‘Roads’ and ‘Roads_Buffer’ layers on
6)
Saved
as S:\Vector2\roadwater_buffer.mxd
7)
Step
3: Using ArcPython to Run Buffer Analysis
1.
Opened
the ArcPy window
2.
Typed
import arcpy (enter)
3. Typed arcpy.Buffer_analysis( “Roads”,”S:\Vector2\roads_buffer300m”,
“100 Meters”, “FULL”, “ROUND”, “ALL”)
4.
Saved
as S:\Vector_Analysis2\arcpyroads.mxd
5.
Turned
the new layer off
6.
Layers
turned on are:
1.
Water.shp
2.
Roads.shp
3.
Water_Buffer_variable.shp
4.
Roads_buffer300m.shp
8)
Step
5: The Union
1.
In
the ‘Water_Buffer_variable’ layer In ‘attribute table’: Add field of type
‘Short Integer’ and name “insd_wbuf”
2.
In
attribute table, under “insd_wbuf’ column, right-clicked to select ‘field
calculator’ and assigned as “1” for all features
3.
In
the ‘Roads_Buffer_300m’ layer In ‘attribute table”: Add field of type ‘Short
Integer’ and named”:insd_rbuf”
4.
In
attribute table, under ‘insd_rbuf’ column, right-clicked to select ‘field
calculator’ and assigned as “1”
9)
Running
a union overlay
1.
Select
Union tool from Overlay toolset in Analysis Tools toolbox
2.
Input
Features: ‘Water_Buffer_variable’’ and ‘Roads_Buffer_300m’
3.
Output
Feature Class: ‘Buffers_Union’
4.
JoinAttributes:
‘All’
5.
Gaps
Allowed ‘checked’
10) Opened the Attribute table for
‘Buffer_Union’ layer and the proper number of attributes was in the table
11) Select by Attributes query:
“insbd_rbuf”= 1 AND “insd_wbuf” = 1
12) Exported ‘selected features’ to “buffer_union_export” shapefile from
the TOC and added new layer to map.
13) Turned off all other buffer layers
14) Step 6: Separating and Excluding
Areas
1.
Added
the conservation_areas’ layer
2.
Chose
the Erase overlay function and used ‘buffer_union_expor’t as the input and the
‘conservation_areas’ as the erase.
3.
Named
this new layer “possible_sites”
15) Converted the ‘possible_sites’ layer
from a multipart layer to a singlepart layer using the ‘Multipart to
Singlepart’ tool.
1.
Named
this new layer “possible_sites_single”
2.
Added
the new field ‘area’
3.
Used
the ‘calculate geometry’ function to answer the questions.
16) Turned off all layers except
‘possible_sites’, ‘roads’ and ‘water’
17) Added Essential Elements
18) Saved file as
S:\Vector2\PossibleCampgroundSites_cmb.mxd
19) Exported file as
S:\Vector2\PossibleCampgroundSites_cmb.jpg
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