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I have a feature class of polygons within a geodatabase and I'm trying to generate points based on the centroid of the polygon using the Feature to Point tool in ArcGIS 9.3. However, I end up with several points that fall just outside of the polygon. So ... is this the wrong tool to be using for this application? Also, am I making the wrong assumption about this tool generating points from the centroids of polygons?

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Within the tools help dialog box, it says that the a point can be created using the polygon's center of gravity (centroid). Does the center of gravity not always fall within the polygon? – dchaboya Jul 30 '12 at 20:42
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The center of gravity can in fact fall outside the polygon. Think of a donut shape, with an empty hole in the middle of the circle polygon. The center of gravity would be there even though the polygon doesn't extend there. – Dan C Jul 31 '12 at 1:50

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The online help indicates that you must check the box to be INSIDE so that a point inside the polygon will be used for the output.

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Yes, that's right. But if you leave it unchecked you are telling it to create the point using the centriod (center of gravity) of the polygon. Is the center of gravity of a polygon not within the polygon? I guess I don't fully understand the tool and the purpouse of having two options for creating points from polygons. – dchaboya Jul 30 '12 at 21:55

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