topic Re: Is it possible to "spatial match"? in SAS Programming

Is it possible to "spatial match"?

hkgejd — Fri, 27 Aug 2021 13:00:06 GMT

Hi everyone

Does anyone know, if it is possible to spatial match?

What I mean is that I have a shape-file with some polygons, and I have another file with a lot of different coordinates. I want to merge the coordinate-dataset with the shape-file, so the coordinates can get the right polygon.

Does my question make sense? Thanks in advance 😀

Re: Is it possible to "spatial match"?

maguiremq — Fri, 27 Aug 2021 13:26:45 GMT

I've had luck in the past with importing the shapefile using PROC MAPIMPORT, and then using PROC GINSIDE to project the coordinates.

Without data, that's all I can give you. Hopefully that helps.

Here's some documentation:

PROC MAPIMPORT

PROC GINSIDE

Re: Is it possible to "spatial match"?

hkgejd — Tue, 31 Aug 2021 13:51:19 GMT

Hi maguiremq

Thanks for your reply!

I tried your suggestion, but I could not really get it to work... If you don't mind, you could try it out?

The shapes I'm trying to spatial match are from this site https://www.efgs.info/data/ under "Denmark".

I did have luck using "proc mapimport". I have taken a subset of this:

data WORK.SHAPE;
  infile datalines dsd truncover;
  input X 7. Y 9. SEGMENT 1. GRD_NEWID:$25.;
datalines;
4442000 3519000 1 1kmN3519E4441
4441000 3519000 1 1kmN3519E4441
4441000 3520000 1 1kmN3519E4441
4442000 3520000 1 1kmN3519E4441
4442000 3519000 1 1kmN3519E4441
;;;;
run;

The dataset I want to match it with is the following:

data WORK.EDMT;
  infile datalines dsd truncover;
  input DDKNcelle1km $12. wgs84_bredde 14. wgs84_laengde 12.;
datalines;
1km_6072_684 54.765037537 11.871144295
1km_6072_684 54.765060425 11.871236801
1km_6072_684 54.765117645 11.871257782
1km_6072_684 54.765144348 11.871356964
1km_6072_684 54.765148163 11.870749474
1km_6072_684 54.765159607 11.870833397
1km_6072_684 54.765193939 11.871382713
1km_6072_684 54.765197754 11.871330261
1km_6072_684 54.765220642 11.870867729
;;;;
run;

Re: Is it possible to "spatial match"?

maguiremq — Thu, 02 Sep 2021 12:37:36 GMT

Sorry, I missed this one in my inbox.

I just did my own test run on my own data, and this is what I did.

proc import
	datafile = "/your/data/here/"
	out = needs_geo (rename = (longitude = x latitude = y)) 
	dbms = csv
	replace;
	guessingrows = 5000;
run;

proc mapimport
	datafile = "/your/shape/file"
	out = shape;
run;

proc sort
	data = needs_geo;
		by x y;
run;

proc sort
	data = shape;
		by x y;
run;

proc ginside
	map = shape
	data = needs_geo
	out = needs_geo_w_shape;
	id var-you-want-from-shape-file;
run;

I am by no means advanced with mapping -- it's something I've learned on my own, and I have a crude working knowledge on how things work.

I would recommend renaming your respective latitude and longitude coordinates on your EDMT dataset to x and y (as I do on the PROC IMPORT).

Essentially, just use my code and tailor it to your data set. Let me know if there are any issues. It worked for me, but I would be careful and check everything to make sure it makes sense. My own local data seemed to make sense.