Coordinates Conversion

[Stephanie_AnneCerado]

Hi,

I'm new to GIS and we have this application that would get a data from an outside system which uses Google Map. We need to convert the coordinates since our map is using a different coordinate system (Philippine Zone III).

Is there an API or any available formula which I could use as a reference to solve this issue?

Thanks

[TimothyKippo]

Hi Stephanie

I am assuming that the data is arriving into ArcMap in some format.  If the data has it's coordinate system defined then it is as simple as using the project tool (Data Management tools -> Projections and Transformations -> Feature) on it to convert it to a featureclass in Philippine Zone III.  If the raw data doesn't have it's projection defined, and coming from Google, you should be able to define it's projection to WGS84 (using the define projection tool in Data Management tools -> Projections and Transformations).

I have run into trouble doing this before where my geographic projection simply won't transform to a projected system no matter how I do it.  To get around this what I did was create a feature dataset with my desired coordinate system defined, then imported the data into the feature dataset.  This worked, forcing the data to conform to my will.  I like when data does that.  That's just a work around in case things go illogical and crazy that does tend to happen from time to time in the GIS world.

Outside of ArcMap I haven't explored coordinate transformations since University, which would probably be obsolete by now, and is rapidly becoming a distant memory.  Let us know how you go.

Cheers,

Tim

[Stephanie_AnneCerado]

Hi Timothy,

Hmn... The data from the outside source will be stored in our SQL Table for now...

We could like to convert that X,Y Coordinate in Philippine Zone III format so that the data that will be retrieved during searching or records from our GIS APP is already converted.

[TimothyKippo]

What is the GIS platform/app that you are using?

[Stephanie_AnneCerado]

ArcGIS 10.2 Desktop

[TimothyKippo]

Hi Steph

The method to convert.

Step 1:  Load your table into an mxd.  Right click on the table and select "Display XY Data".

Step 2: Fill in the window that opens.  You need to specify the X Field and Y Field and the coordinate system.  I believe it should be WGS 1984 if it is using Google.

Step 3: This should open up an "Events" layer (not actual data yet).  First, make sure your data frame coordinate system is set to Philipinne Zone III.  Then you want to right click on your events layer, select Data and then Export data.

Step 4: In the window that opens make sure you have "Use the same coordinate system as:" set to "the data frame".  Specify your output, and that should do it.

If you have any questions about any of the steps I am happy to elaborate.

If it is a task you will be doing regularly you may want to set up a python script.  A script can be set up to run on a schedule as well.

Let me know if you need more direction.

Regards,

Tim

[Stephanie_AnneCerado]

Thanks Timothy

We will try your suggestion. Is it possible that we do the steps above using codes, example, calling a certain built-in method to do those steps? Since the data of Lat, long are being retrieved from the external source. We can't do the steps manually.

[Stephanie_AnneCerado]

BTW Sir, since you have mentioned that a phython script can do the steps, can you give me a reference on how to do that script? We are using VB.Net, we will try to convert the script.