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-rw-r--r--src/de/lmu/ifi/dbs/elki/data/spatial/SpatialUtil.java103
1 files changed, 53 insertions, 50 deletions
diff --git a/src/de/lmu/ifi/dbs/elki/data/spatial/SpatialUtil.java b/src/de/lmu/ifi/dbs/elki/data/spatial/SpatialUtil.java
index 731c021a..607acd1c 100644
--- a/src/de/lmu/ifi/dbs/elki/data/spatial/SpatialUtil.java
+++ b/src/de/lmu/ifi/dbs/elki/data/spatial/SpatialUtil.java
@@ -42,15 +42,23 @@ import de.lmu.ifi.dbs.elki.utilities.datastructures.arraylike.ArrayAdapter;
// numbers start at 1 or 0 depending on the context!
public final class SpatialUtil {
/**
+ * Fake constructor: do not instantiate.
+ */
+ private SpatialUtil() {
+ // Do not instantiate.
+ }
+
+ /**
* Returns a clone of the minimum hyper point.
*
+ * @param box spatial object
* @return the minimum hyper point
*/
public static double[] getMin(SpatialComparable box) {
final int dim = box.getDimensionality();
double[] min = new double[dim];
for(int i = 0; i < dim; i++) {
- min[i] = box.getMin(i + 1);
+ min[i] = box.getMin(i);
}
return min;
}
@@ -58,13 +66,14 @@ public final class SpatialUtil {
/**
* Returns a clone of the maximum hyper point.
*
+ * @param box spatial object
* @return the maximum hyper point
*/
public static double[] getMax(SpatialComparable box) {
final int dim = box.getDimensionality();
double[] max = new double[dim];
for(int i = 0; i < dim; i++) {
- max[i] = box.getMax(i + 1);
+ max[i] = box.getMax(i);
}
return max;
}
@@ -82,7 +91,7 @@ public final class SpatialUtil {
throw new IllegalArgumentException("The spatial objects do not have the same dimensionality: " + box1.getDimensionality() + " " + box2.getDimensionality());
}
boolean intersect = true;
- for(int i = 1; i <= dim; i++) {
+ for(int i = 0; i < dim; i++) {
if(box1.getMin(i) > box2.getMax(i) || box1.getMax(i) < box2.getMin(i)) {
intersect = false;
break;
@@ -107,7 +116,7 @@ public final class SpatialUtil {
}
boolean contains = true;
- for(int i = 1; i <= dim; i++) {
+ for(int i = 0; i < dim; i++) {
if(box1.getMin(i) > box2.getMin(i) || box1.getMax(i) < box2.getMax(i)) {
contains = false;
break;
@@ -120,6 +129,7 @@ public final class SpatialUtil {
* Returns true if this SpatialComparable contains the given point, false
* otherwise.
*
+ * @param box spatial object
* @param point the point to be tested for containment
* @return true if this SpatialComparable contains the given point, false
* otherwise
@@ -132,7 +142,7 @@ public final class SpatialUtil {
boolean contains = true;
for(int i = 0; i < dim; i++) {
- if(box.getMin(i + 1) > point[i] || box.getMax(i + 1) < point[i]) {
+ if(box.getMin(i) > point[i] || box.getMax(i) < point[i]) {
contains = false;
break;
}
@@ -141,14 +151,15 @@ public final class SpatialUtil {
}
/**
- * Computes the volume of this SpatialComparable
+ * Computes the volume of this SpatialComparable.
*
+ * @param box Spatial object
* @return the volume of this SpatialComparable
*/
public static double volume(SpatialComparable box) {
double vol = 1;
final int dim = box.getDimensionality();
- for(int i = 1; i <= dim; i++) {
+ for(int i = 0; i < dim; i++) {
double delta = box.getMax(i) - box.getMin(i);
if(delta == 0.0) {
return 0.0;
@@ -159,7 +170,7 @@ public final class SpatialUtil {
}
/**
- * Compute the volume (area) of the union of two MBRs
+ * Compute the volume (area) of the union of two MBRs.
*
* @param r1 First object
* @param r2 Second object
@@ -170,7 +181,7 @@ public final class SpatialUtil {
final int dim2 = r2.getDimensionality();
assert (!LoggingConfiguration.DEBUG || dim1 == dim2) : "Computing union with different dimensionality: " + dim1 + " vs. " + dim2;
double volume = 1.0;
- for(int i = 1; i <= dim1; i++) {
+ for(int i = 0; i < dim1; i++) {
final double min = Math.min(r1.getMin(i), r2.getMin(i));
final double max = Math.max(r1.getMax(i), r2.getMax(i));
volume *= (max - min);
@@ -179,15 +190,16 @@ public final class SpatialUtil {
}
/**
- * Computes the volume of this SpatialComparable
+ * Computes the volume of this SpatialComparable.
*
+ * @param box Box
* @param scale Scaling factor
* @return the volume of this SpatialComparable
*/
public static double volumeScaled(SpatialComparable box, double scale) {
double vol = 1;
final int dim = box.getDimensionality();
- for(int i = 1; i <= dim; i++) {
+ for(int i = 0; i < dim; i++) {
double delta = box.getMax(i) - box.getMin(i);
if(delta == 0.0) {
return 0.0;
@@ -198,7 +210,7 @@ public final class SpatialUtil {
}
/**
- * Compute the volume (area) of the union of two MBRs
+ * Compute the volume (area) of the union of two MBRs.
*
* @param r1 First object
* @param r2 Second object
@@ -210,7 +222,7 @@ public final class SpatialUtil {
final int dim2 = r2.getDimensionality();
assert (!LoggingConfiguration.DEBUG || dim1 == dim2) : "Computing union with different dimensionality: " + dim1 + " vs. " + dim2;
double volume = 1.0;
- for(int i = 1; i <= dim1; i++) {
+ for(int i = 0; i < dim1; i++) {
final double min = Math.min(r1.getMin(i), r2.getMin(i));
final double max = Math.max(r1.getMax(i), r2.getMax(i));
volume *= (max - min) * scale;
@@ -231,7 +243,7 @@ public final class SpatialUtil {
assert (!LoggingConfiguration.DEBUG || dim1 == dim2) : "Computing union with different dimensionality: " + dim1 + " vs. " + dim2;
double v1 = 1.0;
double v2 = 1.0;
- for(int i = 1; i <= dim1; i++) {
+ for(int i = 0; i < dim1; i++) {
final double emin = exist.getMin(i);
final double emax = exist.getMax(i);
final double amin = addit.getMin(i);
@@ -259,7 +271,7 @@ public final class SpatialUtil {
assert (!LoggingConfiguration.DEBUG || dim1 == dim2) : "Computing union with different dimensionality: " + dim1 + " vs. " + dim2;
double v1 = 1.0;
double v2 = 1.0;
- for(int i = 1; i <= dim1; i++) {
+ for(int i = 0; i < dim1; i++) {
final double emin = exist.getMin(i);
final double emax = exist.getMax(i);
final double amin = addit.getMin(i);
@@ -276,12 +288,13 @@ public final class SpatialUtil {
/**
* Computes the perimeter of this SpatialComparable.
*
+ * @param box spatial object
* @return the perimeter of this SpatialComparable
*/
public static double perimeter(SpatialComparable box) {
final int dim = box.getDimensionality();
double perimeter = 0;
- for(int i = 1; i <= dim; i++) {
+ for(int i = 0; i < dim; i++) {
perimeter += box.getMax(i) - box.getMin(i);
}
return perimeter;
@@ -306,7 +319,7 @@ public final class SpatialUtil {
// the overlap volume
double overlap = 1.0;
- for(int i = 1; i <= dim; i++) {
+ for(int i = 0; i < dim; i++) {
// The maximal value of that overlap box in the current
// dimension is the minimum of the max values.
omax = Math.min(box1.getMax(i), box2.getMax(i));
@@ -344,7 +357,7 @@ public final class SpatialUtil {
double vol1 = 1.0;
double vol2 = 1.0;
- for(int i = 1; i <= dim; i++) {
+ for(int i = 0; i < dim; i++) {
final double box1min = box1.getMin(i);
final double box1max = box1.getMax(i);
final double box2min = box2.getMin(i);
@@ -383,9 +396,9 @@ public final class SpatialUtil {
double[] min = new double[dim];
double[] max = new double[dim];
- for(int i = 1; i <= dim; i++) {
- min[i - 1] = Math.min(box1.getMin(i), box2.getMin(i));
- max[i - 1] = Math.max(box1.getMax(i), box2.getMax(i));
+ for(int i = 0; i < dim; i++) {
+ min[i] = Math.min(box1.getMin(i), box2.getMin(i));
+ max[i] = Math.max(box1.getMax(i), box2.getMax(i));
}
return new ModifiableHyperBoundingBox(min, max);
}
@@ -414,27 +427,33 @@ public final class SpatialUtil {
/**
* Compute the union of a number of objects as a flat MBR (low-level, for
- * index structures)
+ * index structures).
*
* @param data Object
* @param getter Array adapter
+ * @param <E> object type
+ * @param <A> data value type
* @return Flat MBR
*/
public static <E extends SpatialComparable, A> double[] unionFlatMBR(A data, ArrayAdapter<E, ? super A> getter) {
final int num = getter.size(data);
assert (num > 0) : "Cannot compute MBR of empty set.";
- final E first = getter.get(data, 0);
- final int dim = first.getDimensionality();
- double[] mbr = new double[2 * dim];
- for(int d = 0; d < dim; d++) {
- mbr[d] = first.getMin(d + 1);
- mbr[dim + d] = first.getMax(d + 1);
- }
+ final int dim;
+ final double[] mbr;
+ { // First entry
+ final E first = getter.get(data, 0);
+ dim = first.getDimensionality();
+ mbr = new double[2 * dim];
+ for(int d = 0; d < dim; d++) {
+ mbr[d] = first.getMin(d);
+ mbr[dim + d] = first.getMax(d);
+ }
+ } // Remaining entries
for(int i = 1; i < num; i++) {
E next = getter.get(data, i);
for(int d = 0; d < dim; d++) {
- mbr[d] = Math.min(mbr[d], next.getMin(d + 1));
- mbr[dim + d] = Math.max(mbr[dim + d], next.getMax(d + 1));
+ mbr[d] = Math.min(mbr[d], next.getMin(d));
+ mbr[dim + d] = Math.max(mbr[dim + d], next.getMax(d));
}
}
return mbr;
@@ -449,24 +468,8 @@ public final class SpatialUtil {
public static double[] centroid(SpatialComparable obj) {
final int dim = obj.getDimensionality();
double[] centroid = new double[dim];
- for(int d = 1; d <= dim; d++) {
- centroid[d - 1] = (obj.getMax(d) + obj.getMin(d)) / 2.0;
- }
- return centroid;
- }
-
- /**
- * Returns the centroid of the specified values of this SpatialComparable.
- *
- * @param obj Spatial object to process
- * @param start the start dimension to be considered
- * @param end the end dimension to be considered
- * @return the centroid of the specified values of this SpatialComparable
- */
- public static double[] centroid(SpatialComparable obj, int start, int end) {
- double[] centroid = new double[end - start + 1];
- for(int d = start - 1; d < end; d++) {
- centroid[d - start + 1] = (obj.getMax(d + 1) + obj.getMin(d + 1)) / 2.0;
+ for(int d = 0; d < dim; d++) {
+ centroid[d] = (obj.getMax(d) + obj.getMin(d)) / 2.0;
}
return centroid;
}
@@ -482,7 +485,7 @@ public final class SpatialUtil {
if(box1.getDimensionality() != box2.getDimensionality()) {
return false;
}
- for(int i = 1; i <= box1.getDimensionality(); i++) {
+ for(int i = 0; i < box1.getDimensionality(); i++) {
if(box1.getMin(i) != box2.getMin(i)) {
return false;
}
generated by cgit v1.2.3 (git 2.25.1) at 2024-05-17 12:52:31 +0000