Multiple ring buffer with attributes

Question

Building on ArcGIS: inside buffer with attributes?, I'd like to be able to create multiple ring buffers, while retaining (and possibly dissolving on) attribute values. How can this be done?

Answer 1

OK, how I did this, is loop through creating ring buffers on objects, and saving the output as a new featureclass in a standlone datasets collection. I then merged the featureclasses, like so:

tmp_merge = "path to area"\+ "tmp_merge"  
final_out_path_agg = final_staging + "_Agg"
final_out_path_simp = final_staging +  "_Simp"

#check if files exist and delete if they do; assume nothing
if (arcpy.Exists(tmp_merge)):
    arcpy.Delete_management(tmp_merge)   

#set up folder to search for polygon data
arcpy.env.workspace = scratchDB + "mytmpBuff.gdb/Polygons/"
#collate FC
fcs = arcpy.ListFeatureClasses()
L = []
count = 0
try:
    for fc in fcs:
        #append to array ready for merging
        L.append(fc)
        count = count + 1
except:
    print "Error collating FeatureClasses."

try:
    if count > 1:
        arcpy.Merge_management(L, tmp_merge)
    elif count == 0:
        arcpy.AddMessage("No FeatureClass Polygons located.")
        arcpy.AddMessage("Error collating FeatureClasses.")
        sys.exit(-1) 
except:
    arcpy.AddMessage("Error merging FeatureClasses.")   

Then dissolved them

#overlaps dissolved
arcpy.Dissolve_management(tmp_merge, final_out_path_agg, "Name", [["RunID","FIRST"],["AltiLwr","FIRST"],["AltUpr","FIRST"],["TimeSl","FIRST"],["ConcentrationBand","FIRST"],["ConcLvl","FIRST"],["IsC","FIRST"]])  
arcpy.DeleteField_management(final_out_path_agg, "NAME") 

The buffers are created in a loop and stored in arcpy.env.workspace = scratchDB + "mytmpBuff.gdb/Polygons/" before I later loop through them.

It works, or it does if I have understood your issue correctly!

Answer 2

Below is my answer. Although it bears little resemblance now to Hairy's example, it was only by stepping through and understanding his code that I was able to find my own solution, so thank you!

multi-ring-buffer.py: Create multiple ring buffers, keeping named attributes of parent feature class.

Process:

• create inside only buffer for each of the specifed buffer widths
• store buffer width used as an attribute
• merge all buffers into a single feature class, ensuring largest width first so narrower ones are drawn on top

Usage:

multi-ring-buffer [feature class]  [workspace]  [output feature class]  [widths list]  [attributes to keep]

multi-ring-buffer R:\data.gdb\Foobar_ply  X:\maps\buffers.gdb  Foobar_rings   50,-50,-100,-300,-600  NAME,TYPE

Workspace must exist. The width and attribute parameters must be comma separated and have no spaces. Requires Arcgis 10, Arcinfo license level.

(c) 2012 Environment Yukon, matt.wilkie@gov.yk.ca Licensed under the MIT license: http://www.opensource.org/licenses/MIT

import arcpy
from arcpy import env

in_fc = arcpy.GetParameterAsText(0)                   # features to buffer
wspace = arcpy.GetParameterAsText(1)                # output workspace
out_fc = arcpy.GetParameterAsText(2)                 # finished result
distances = arcpy.GetParameterAsText(3).split(',')  # list of buffer widths 
# parse list of attributes to keep into semi-colon separated as expected by buffer tool
dissolveFields = arcpy.GetParameterAsText(4).replace(',',';')

env.workspace = wspace

sideType = "OUTSIDE_ONLY"
endType = "ROUND"
dissolveType = "LIST"

buffered_fcs = []
for distance in distances:
    buf_fc = arcpy.ValidateTableName('xxx_' + out_fc + distance)
    print("...buffering {0} into {1} with width {2}".format(in_fc, buf_fc, distance))

    arcpy.Buffer_analysis(in_fc, buf_fc, distance, sideType, endType, dissolveType, dissolveFields)

    # store buffer width as attribute value
    arcpy.AddField_management(buf_fc, 'Width', "TEXT", "", "", 16)
    arcpy.CalculateField_management(buf_fc, 'Width', distance, "PYTHON")

    buffered_fcs.append(buf_fc)

# arrange buffers from largest to smallest width
# so the draw order is correct after merging
buffered_fcs.sort()
buffered_fcs.reverse() 

print("...Merging intermediate buffers into {0}".format(out_fc))
arcpy.Merge_management(buffered_fcs, out_fc)

# remove temporary intermediate files
print("...Removing intermediate files")
for fc in arcpy.ListFeatureClasses('xxx_*'):
    arcpy.Delete_management(fc)

In source code management at http://code.google.com/p/maphew/source/browse/arcplus/AttributedMultiRingBuffer.py

The resulting ring buffers displayed with multi-field unique values in arcmap: