topic calculate distance using projected coordinates in SAS Programming

calculate distance using projected coordinates

michokwu — Fri, 20 Mar 2020 01:40:34 GMT

Hello experts,

I am trying to measure the distance between locations but it returns null values, no error message. The XY coordinates were generated using ARCGIS projected coordinate system. I am using SAS 9.4. See below my codes and table. Thank you

/*Calculate the distance*/
data state.c000dist;
set state.c000_odxy;
format distance best12.;
distance=geodist(h_y, h_x, w_y, w_x);
run;

data state.c000dist;
set state.c000_odxy;
format distance best12.;
distance=geodist(h_y, h_x, dest_y, dest_x, 'M');
run;

w_1	h_1	h_x	h_y	w_x	w_y	distance
295101011001003	291892204451015	1549820	3396739	737017.8	4270860
295101011001003	295101011001003	1704594	3199620	737017.8	4270860
295101011001003	291892202003011	1606500	3013045	737017.8	4270860
295101011001003	290997002112025	1590932	3380332	737017.8	4270860
295101011001003	290997001091013	1591513	3388368	737017.8	4270860
295101011001003	295101063002004	1586158	3403888	737017.8	4270860
295101011001003	290997014041047	1597463	3395733	737017.8	4270860
295101011001003	171635040011097	1057384	3381480	737017.8	4270860
295101011001025	295101021003001	1538631	3137542	737540	4270380
295101011001025	295101011001025	1537792	3138305	737540	4270380
295101011001025	295101021001013	1536083	3135691	737540	4270380
295101011001025	171194034022007	1545883	3145134	737540	4270380
295101011001025	290997014042011	1591510	3221054	737540	4270380
295101011001026	291879507003038	1615559	2994634	737669.6	4270308
295101011001026	190130007001013	1790677	2920093	737669.6	4270308
295101011001026	295101105001027	1790300	2919619	737669.6	4270308
295101011001026	291892126002008	1787475	2915743	737669.6	4270308
295101011001026	291892126001005	1783127	2913354	737669.6	4270308
295101011001029	291892199006006	1783154	2913153	736570.1	4270925

Re: calculate distance using projected coordinates

ChrisNZ — Fri, 20 Mar 2020 02:46:05 GMT

The function geodist requires latitude and longitude coordinates.

Can you export that for ARCGIS?

Re: calculate distance using projected coordinates

s_lassen — Fri, 20 Mar 2020 09:31:02 GMT

As @ChrisNZ already mentioned, the GEODIST function uses longitude and latitude, not projected coordinates. Projected coordinates are coordinates for a projection of the Earth sphere unto a flat surface. And there are a lot of different projection types (see https://resources.arcgis.com/en/help/main/10.1/018z/pdf/projected_coordinate_systems.pdf ). You will have to find a way to convert the projected coordinates to longitude and latitude in order to use GEODIST.

Which coordinates are you using?

Re: calculate distance using projected coordinates

michokwu — Sat, 21 Mar 2020 19:25:31 GMT

That's right. I converted to feet and then miles. Thank you

Re: calculate distance using projected coordinates

michokwu — Sat, 21 Mar 2020 19:28:24 GMT

That's right. I converted to feet and then miles. Thank you.

I used the NAD_1983_UTM_Zone_15N