| Efficient
computation of Region Algebra Operators |
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| Example:
s1 included s2 |
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| s1 =
{(x1,x1'), (x2,x2'), …} |
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| s2 =
{(y1,y1'), (y2,y2'), …} |
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| (i.e.
assume each consists of disjoint regions) |
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| Algorithm: |
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| if xi
< yj then i := i + 1 |
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| if xi' > yj' then j := j + 1 |
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| otherwise:
print (xi,xi'), do i := i + 1 |
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| Can
do in sub-linear time when one region is very |
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| small |
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