Line and Polygon with same geometry should have same centroid?

Question

Hello,

I have two different line and polygon features with the same geometry. I calculated the X and Y coordinate values using the python expressions !shape.TRUECENTROID.X! and !shape.TRUECENTROID.Y! and the returned values in both features are different.

I'm doing something wrong?

Can any one help me?

Best regards,

JA

danretired · Answer

If you want someone from esri, then the quickest route is to contact Tech Support.

The assumption has nothing to do with the number of points, it is how the points are used.  The only way they would return the same value is if the average of the coordinates were used (perhaps ignoring the duplicate first and last point... even that isn't clear).

The centroid and truecentroid for polygons will also differ for multipart features.  In fact the centroid may not even be within the polygon (or polyline) since they are weighted.  Hopefully you haven't been looking at multipart shapes?

JulioAAlmeida · Answer

Dan Patterson,

Thanks again for your reply.

You are probably right, but I was hoping that someone from ESRI confirm it!

Even do, all geometries have the same number of points and they should return the same values.

Best regards,

JA

danretired · Answer

So my initial post stands.  If you need the truecentroid use the polygon if you aren't sure which algorithm is used for closed-loop polylines