com.vividsolutions.jts.index.quadtree
Class IntervalSize
java.lang.Object
com.vividsolutions.jts.index.quadtree.IntervalSize
public class IntervalSize
extends java.lang.Object
Provides a test for whether an interval is
so small it should be considered as zero for the purposes of
inserting it into a binary tree.
The reason this check is necessary is that round-off error can
cause the algorithm used to subdivide an interval to fail, by
computing a midpoint value which does not lie strictly between the
endpoints.
static int | MIN_BINARY_EXPONENT - This value is chosen to be a few powers of 2 less than the
number of bits available in the double representation (i.e.
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static boolean | isZeroWidth(double min, double max) - Computes whether the interval [min, max] is effectively zero width.
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MIN_BINARY_EXPONENT
public static final int MIN_BINARY_EXPONENT
This value is chosen to be a few powers of 2 less than the
number of bits available in the double representation (i.e. 53).
This should allow enough extra precision for simple computations to be correct,
at least for comparison purposes.
isZeroWidth
public static boolean isZeroWidth(double min,
double max)
Computes whether the interval [min, max] is effectively zero width.
I.e. the width of the interval is so much less than the
location of the interval that the midpoint of the interval cannot be
represented precisely.