Latest Contributions by SrikanthSivashankaran

I'm working in ArcMap 10.1. Currently examining the segment of states with a geographical hierarchy of 1. Counties, coextensive with state boundaries 2. Within counties, unincorporated areas and incorporated places But incorporated places are in most of these cases not restricted to one county; i.e., a given city can span multiple counties. Although these are to some extent exceptional -- most cities are entirely contained within one county -- not all are of this type. I know how to do an intersect, calculate area-weighted populations for the resulting segments of places within counties, etc. But I'm wondering if anyone could give me some feedback on how to take an orderly approach to deducting, from the county population numbers, the population of incorporated places lying within, either area-weighted (where the place spans more than one county), or entire: the result I'm looking for would be the population of the balance of the county (i.e., the population of unincorporated areas). By orderly approach, I mean, how should I manage and reshape the data, use database operations, etc. The process of doing what I'm talking about is pretty straightforward when I'm looking at a small set of features and can analyze them piece-by-piece, but I'm looking at a huge set of features. It may be worth noting that the attribute tables for the places layers do not have a foreign key field for the counties in which they lie, which, perhaps, was obvious from the fact that they may span multiple counties. My apologies if I've set this forth in a confusing way. Thanks in advance for any help you could provide! ... View more

Hello, I am attempting to intersect two polygons and am getting a warning 000117: empty output generated that I can't seem to shake.  After browsing through the forums, I have made sure that: 1. I clear 'selected features' before performing the intersect 2. Environments are at defaults 3. Input and output coordinate systems are in accord Are there other possibilities people are aware of for why this might be happening? Thanks in advance, Dub ... View more

Hello, My apologies in advance if I'm getting the terminology wrong or missing something obvious. I'm interested in assessing how well a facility is situated within its service district by getting a rough calculation of a proxy for the potential cost of transportation to that facility (in my project, facilities = schools and service area = school districts) I know how to calculate, given a distance, a service area for each facility; I'm interested in reversing the inputs.  Is there a way to calculate the distance required to cover a service area, given the facility's location and its polygonal service district? If I were to neglect the road network, I would try to find a way calculate the "average" distance from all points in each polygon to the facility location (using integrals?), but I don't know how to do that either. Thanks in advance for any help you may be able to provide, Dub ... View more

Hello, My apologies in advance if I get the terminology wrong or am asking a really dumb question - am learning arcgis for a class. I have a census boundary file of school districts in a state.  I'm looking for a way to dissolve or merge all adjacent pairs of polygons in this shapefile - I am interested in the shape of every hypothetical merger of two districts.  I was able to use cmaene's "Find Adjacent and Neighboring Polygons" tool http://resources.arcgis.com/gallery/file/Geoprocessing-Model-and-Script-Tool-Gallery/details?entryID=50F58FCF-1422-2418-884B-A053393CEF92 to generate a csv with a record for each shape ID and fields for the shape ID of every adjacent polygon.  EDIT: I should probably make it clear that since there are many, many different ways to group the layer of school districts into pairs of adjacent polygons, I don't think the output for this project could be in a single layer, but I don't know what other formats are possible.  How might I approach this problem? Do I need to learn some scripting? Thanks in advance for any help you can provide. ... View more