247 ideas posted
I am looking for a way to get the ACS data for a radius around a given point. Using the FCC's API I can get the Census Tract and Block number to use. Does anyone know of a way to get the Census tract numbers say within a 5 mile radius?
Submitted by Community Member 2 years ago
Plot it on a map, draw a circle, find all points inside the circle.
Plug names into Google maps, parse distance between points, find any distance less then or equal to 5.
I guess I was hoping for an easier method, but I can make this work. Thanks!
Glad to help, I don't know if there is a database you can get to that holds coordinates, but if you can get a hold of one, finding relative positions should be easy as well.
Phillip, how do you find all internal points inside the circle using the API?
The API shouldn't handle getting points inside a circle. This kind of math should be handled within the program prior to forming a request to the API (to get a list of geographies you want to make a request on).
Phillip, I just wanted to point out that "finding all points inside the circle" and then I guess testing ALL points to find all geographies involved within the circle before retrieving the demographic data for those geographies may be theoretically possible but I think practically impossible. There must be a better way to do it. I am curious to know for example how this is done on American Fact Finder where we can get very fast a list of geographies within a circle or a rectangle.
They do exactly as you theorize is impractical.
Check the description of the OGC WMS compliant services at tigerweb.geo.census.gov/tigerwebmain/TIGERweb_main.html to see if there's something there that will work for you.
You can use the MABLE/Geocorr12: Geographic Correspondence Engine by Missouri Census Data Center.
The point and distance filter lets you define a circle.
when you get a TIGER geography file there should be two fields (intplat and intplng) that provide the centroid point for the geography in question...you can use these to calculate the distance
Just to clarify. An Internal Point in TIGER is not always equal to the centroid. We ensure that the internal point falls inside the entity and on a land face if there is one.
Nice catch gio.
I am working on a similar problem. I have spent quite some time digging through the Tiger web apis and can't figure out how to access those intptlat or lon data. The API services all appear to be geared towards different things vs purely just querying for data, and sadly this isn't something you can query as part of the normal census API.
Would greatly appreciate assitance with which service, operation, and parameters are needed.
Submitted by maraaverick 1 year ago
Submitted by claudia.cassidy 1 year ago
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