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Sometimes when I snap the ends of 2 LineStrings together and I check the st_distance between those endpoints I get a value in the order of 1.1E-10 while at the same time when I check for equality of those endpoints I get the value 'true'.

How can I snap 2 lines so the st_distance between them is 0?

I am using QGIS 1.9.0-Master and a PostgreSQL database 9.1.7 with PostGIS 1.5.3-1.

share|improve this question
Where are you doing the tests, QGis or PostGIS? – Nicklas Avén Feb 15 '13 at 5:58
I do the tests in PostGIS. – mrg Feb 16 '13 at 9:47

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