Normally when I call the #intersection method on a multipolygon to find the intersection shape on another multipolygon I get a multipolygon returned back to me. Either that or something else I can then call the #area function on.

Well, 150 spatial joins into a list of zoning shapefiles (ie this is a rare case) I'm scanning through my code throws an error because it can't call the #area method on a CAPIGeometryCollection. I am having problems linking qgis with my postgresql db and don't know how to create a kml for a "GeometryCollection" object

Here's what the WKT string output for the intersection shape looks like:

"GEOMETRYCOLLECTION (LINESTRING (1480424.245856002 596629.5658560097, 1480362.875856012 596566.8158560097), LINESTRING (1480362.875856012 596566.8158560097, 1480293.995856002 596496.4358560145), LINESTRING (1480293.995856002 596496.4358560145, 1480235.625856012 596435.0658560097), LINESTRING (1480235.625856012 596435.0658560097, 1480186.495856002 596385.8158560097), LINESTRING (1480186.495856002 596385.8158560097, 1480146.125856012 596345.3758560121), LINESTRING (1480146.125856012 596345.3758560121, 1480141.125856012 596341.3158560097), LINESTRING (1480141.125856012 596341.3158560097, 1480090.995856002 596301.3158560097), LINESTRING (1480090.995856002 596301.3158560097, 1480044.875856012 596263.8758560121), LINESTRING (1480044.875856012 596263.8758560121, 1480005.745856002 596231.995856002), POLYGON ((1480512.6034600246 596678.2322904326, 1480512.598981008 596678.1839810014, 1480511.7765895594 596677.7314431852, 1480512.6034600246 596678.2322904326)), POLYGON ((1480005.745856002 596231.995856002, 1479874.7139810026 596136.0839810073, 1479816.8752310127 596088.7502310127, 1479758.3752310127 596040.8127310127, 1479707.547731012 595999.19689875, 1479758.375856012 596040.8158560097, 1479816.875856012 596088.8158560097, 1479875.375856012 596136.6258560121, 1480005.745856002 596231.995856002)))"


I could skip this error with a rescue block or a next identifier and move on per case but that's not very professional. Documentation on this issue is extremely slim so I figured I'd contribute with a stackexchange question

Plus (just checked), I can't load GEOMETRYCOLLECTION wkts into qgis (currently passing in the polygons &amp; line string arghhs each by hand)

(note: someone with >300 points or whatever mark this question with these new question tags: 'geometry-collection' &amp; 'multi-polygon', they're pretty basic to gis I think, esp the multipolygons, thanks)

EDIT:
I could pluck out the polygon(s) from these collections, but I'm wondering what these linestrings mean (i.e. maybe they're the exterior rings of polygons that are part of the intersect shape)


Question: Black hole collision and the event horizon
Answer: The apparent horizon is only affected to the point that the curvature around one black hole is modified by the gravitational field of the other.

The event horizon as defined by the boundary of the causal past of future conformal infinity gets modified in advance of significant changes in curvature, but this precisely what you would expect from a global teleological definition. See Hawking and Penrose for more details.