topic shape files with same projection but don't overlay in ArcGIS Viewer for Flex Questions

shape files with same projection but don't overlay

Environgis — Sat, 09 Aug 2014 10:58:01 GMT

I have data of shape files (lakes of same area) from two different years...one file have UTM WGS1984 projection while other have WGS1984 Zone 43N,I have to overlay them for analysis but even after giving them same projection, it doesn't work.Any solution please?

Re: shape files with same projection but don't overlay

DanPatterson_Retired — Sat, 09 Aug 2014 13:16:36 GMT

the first file has no zone designation. I would check both files to see if they are indeed 43N...perhaps one is a GCS which means that it is not projected at all.

Re: shape files with same projection but don't overlay

RobertScheitlin__GISP — Sat, 09 Aug 2014 14:56:19 GMT

Environ gis,

Are you sure you are posting in the right space? Are you using my ArcGIS Viewer for Flex Shapefile widget? It may help to attach your shapefiles so we can look at their actual projection.

Re: shape files with same projection but don't overlay

curtvprice — Sat, 09 Aug 2014 16:05:39 GMT

after giving them same projection

This may be a key here. Did you use the Define Projection tool? That is the wrong tool to use as it only changes the description of the xy values. You should use the Project tool if you intend to project the data from one coordinate system into another.

Re: shape files with same projection but don't overlay

stefanstamenov — Sat, 09 Aug 2014 20:24:06 GMT

Project the layers again in one projection.

Re: shape files with same projection but don't overlay

Environgis — Sun, 10 Aug 2014 10:47:35 GMT

i projected them in 43N and in UTM as well but it didn't work.

Re: shape files with same projection but don't overlay

DanPatterson_Retired — Sun, 10 Aug 2014 12:07:12 GMT

Assuming you are using ArcMap, go into ArcCatalog and copy and paste the coordinate system information. One may be "defined" as UTM 43N but it may not be projected as such. If they were properly defined and/or projected they would line up. The error lies with way this was done.

Re: shape files with same projection but don't overlay

Environgis — Mon, 11 Aug 2014 14:38:23 GMT

Thank you Sir.. in Arc Catalog, files are projected much better as compared to arc map

Re: shape files with same projection but don't overlay

Environgis — Tue, 12 Aug 2014 09:07:00 GMT

As I have to find out lakes of 2005 that are present in 2013, newly appeared and disappeared lakes... can you recommend which tool I should use? e.g intersect or ???

Re: shape files with same projection but don't overlay

curtvprice — Tue, 12 Aug 2014 18:22:20 GMT

Union is probably the tool you want.