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28

Like everybody else, I could give you an answer with code, but I don't think somebody has explained to you that you are doing something that is fundamentally wrong. Why are you hitting this error? Because you are calling geocode every time somebody views your page and you are not caching your results anywhere in the db! The reason that limit exists is to ...


21

For that many records, don't even consider a web service. They will throttle or cut you off before you can finish your task. So then your option becomes to run it locally, and for that you have several commercial or free options. The free options will use the census TIGER dataset which you will need to load into a spatial database. You can find libraries ...


18

GDAL user-friendliness is basically nonexistent, but hot damn does it ever work well. I wrote up this guide to my own georeferencing experiments a few years ago: http://mike.teczno.com/notes/flea-market-mapping.html It's a bit out of date, but the basic elements are there: find matching points between your image and a reference map (I'd now recommend ...


18

ZIP codes are a habitually abused geography. It's understandable that people want to use them because they are so visible and well-known but they aren't well suited to any use outside the USPS. ZIP codes aren't associated with polygons, they are associated with carrier routes and the USPS doesn't like to share those. Some ZIP codes are points e.g. a ZIP ...


18

I work at SmartyStreets (an address verification company). Our service is free for nonprofit organizations (school, library, church, charity...), so if you fit that classification, there's no charge for our unlimited service. Ragi recommends against a web-service, however, our API can easily clean, standardize and geocode 20 million addresses for you in ...


15

Have a look at the Geocoder::US 2.0, the successor to geocoder.us: http://github.com/geocommons/geocoder It's a ruby port of the perl module by the same author.


14

I did a simple comparison a year ago showing eleven different geocoding services, free ones as well as pay services, and the results are in a google spreadsheet. I work at SmartyStreets, so you'll see that listed in the first column but not in first place. I tried to make the comparison unbiased so the results are actually useful. I have now opened the ...


13

The ISO 3166-1 official site is probably the most updated source for the two-letter codes. Unfortunately, they don't have the alpha-3 online, quoting their site: Where can I find the ISO 3166-1 alpha-3 country code for free download on the ISO 3166/MA Website? Nowhere. The alpha-3 code is not made available free of charge. You can buy the ...


13

From Text to Geographic Coordinates: The Current State of Geocoding Daniel W. Goldberg, John P. Wilson, and Craig A. Knoblock Abstract: This article presents a survey of the state of the art in geocoding practices through a cross-disciplinary historical review of existing literature. We explore the evolving concept of geocoding and the fundamental ...


13

There's no strict algorithmic relationship between latitude and longitude and zip code - they're all custom areas generated by the postal service. You need access to a dataset that codes polygons / polygon centroids by zip code. 1) Complex Traditionally, this task (coupled with address lookup) is termed 'Geocoding'. The most convenient method for full ...


12

I think Sasa is right, on both counts. In terms of sending all your addresses at once, one option is to send the requests at intervals. In the past when using JavaScript I have opted to delay requests by 0.25 (seems to work!) seconds using the setTimeout( [FUNCTION CALL] , 2500 ) method. In .NET i have opted for: System.Threading.Thread.Sleep(250); ...


12

Ok Ben, here are my assumptions: 1) You've already got your data (I had some address points in a shapefile, and I downloaded census tract and census block shapefiles for Missouri). 2) You've already geocoded your address points and you're comfortable projecting the data. 3) You're comfortable with an OGR/PostGIS solution (both free). Here are some ...


11

Reverse Geocode Tool Documentation. Your data needs to be in a format that ArcGIS will recognize as a layer (shapefile, geodatabase feature class, etc.). If you just have XY's in a table, consider adding your table to ArcMap then using the add XY data tool to create a layer you can use in the reverse geocode tool.


10

There is definitely a privacy implication here - particularly if you are working with small batches of data. Anyone who is attempting to mine the data stream will be able to make assumptions that all requests in the same batch have something in common - even if the medical condition or personal information is not disclosed over the wire. A better technique ...


10

You could try the Street Address to Coordinates tool from the Data Science Toolkit. This API takes either a single string representing a postal address, or a JSON-encoded array of addresses, and returns a JSON object with a key for every address. The value for each key is either null if no information was found for the address, or an object containing ...


10

The primary industry that uses this is the real estate industry, and planning and government. The TRS system is the basis for the legal descriptions that describe the locations of land parcels in most of the United States. Legal Description - Wikipedia There are a number of ways that the bounds of a land parcel may be described, but at some point, whether ...


9

I haven't had a chance to test out the Nominatim and Geocoder US geocoders. My understanding though is that the Geocoder and Nominatim can't be run directly in the database, which to me is a big disadvantage because it makes them difficult to use in things like triggers or for batch updates directly in the database. PostGIS geocoder being a pure ...


9

I have heard about simplegeo api https://simplegeo.com/docs/api-endpoints/simplegeo-context May work for you


9

IPInfoDB can be used. They don't have a query limit, but they will throttle you to 1 response/sec if you request too frequently. Alternately, if you feel like writing a little bit more code, you can download their database and run the batch queries yourself. I can't imagine it'd take long to set up, and it will process your 30k IP addresses quite quickly. ...


9

the best suitable option is not geonames OR openstreetmap but both, Geonames is good for city data, and Openstreetmap for streets, if you use both you will get a good dataset for geocoding. that's the goal of gisgraphy, use the two datasets to get the best relevance.


8

I do know of two web-based solutions that might be worth taking a look at: Map Rectifier from MetaCarta MapWarper created by Tim Waters I'm pretty sure Tim Waters open sourced his code, so even if these particular tools don't suit your needs, looking at their source might give you some insights. Sorry, I can't post more than one external link because ...


8

If using the Google Geocoding API or another online source is your preference rather than local options, I'd suggest looking into the Tor Project (easily installed through the bundle called 'the Vidalia Bundle'). Tor protects you by bouncing your communications around a distributed network of relays run by volunteers all around the world: it prevents ...


8

County Level (some states go back to 1776) http://publications.newberry.org/ahcbp/ (in lat/lng) you can use this to attach census data (where available) to the county polygons (you maybe doing this already) But downloaded the GIS Data and there is a wealth of facts on changes etc. with dates and sources. A worthy start. Finding GIS (geocoder. address ...


8

Geocoding locally with encrypted files on a secure server would definitely be the gold standard for privacy. Using Tor would be the next best thing, if geocoding using a remote API is needed. Tor protects you by bouncing your communications around a distributed network of relays run by volunteers all around the world: it prevents ... the sites you ...


8

It sounds like you are hitting the simultaneous request limit imposed by Google (though I cannot find a reference to what the limit actually is). You will need to space your requests out so that you do not send 125 requests all at once. Note that there is also a 2500 geocode request per day limit. Consult the Google Geocoding Strategies document for more ...


8

Leaflet itself does not provide geocoding services, but you can look at Nominatim for example. http://wiki.openstreetmap.org/wiki/Nominatim


8

"Class C" is a historical reference meaning that your location data is summarized to the /24 level. For example, even if 203.0.113.1 and 203.0.113.254 happen to be in very different physical locations, the database will have only one lat/long for the entire 203.0.113.0/24 network. Potentially useful generalizations about accuracy: If you summarize to the ...


8

I see them as separate activities. Geocoding is the process of taking coded location information (such as addresses or grids) and turning it into explicit location information (X and Y coordinates, usually). Reverse geocoding is the opposite, taking XY data and locating the nearest address, grid, etc. Georeferencing is the process of taking a raster image ...


7

I don't think this question is explicitly geographic, because you're only interested in names, so you may want to ask it on SO. You could answer your question with two pieces of information: the state and the corrected county name. To perform the corrections, you'd likely want to use the Levenshtein distance (example & java implementation) to match the ...


7

This is an excellent question that I have been asked a number of times lately since I work for an address verification company called SmartyStreets. First off, a postal address represents a single locatable point on the map. An address by itself is inherently benign because it doesn't have any additional information. Drawing a point on a map doesn't do ...



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