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Fix equals and hashcode to do exact comparisons

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git-svn-id: https://svn.apache.org/repos/asf/commons/proper/math/trunk@767782 13f79535-47bb-0310-9956-ffa450edef68
This commit is contained in:
William Barker 2009-04-23 04:09:27 +00:00
parent 7d6a1cec1a
commit e1452ca6ea
1 changed files with 21 additions and 6 deletions
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27
src/java/org/apache/commons/math/linear/SparseRealVector.java
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@ -1224,7 +1224,11 @@ public class SparseRealVector implements RealVector {
return getData(); return getData();
} }
/** {@inheritDoc} */ /** {@inheritDoc}
* <p> Implementation Note: This works on exact values, and as a result
* it is possible for {@code a.subtract(b)} to be the zero vector, while
* {@code a.hashCode() != b.hashCode()}.</p>
*/
@Override @Override
public int hashCode() { public int hashCode() {
final int prime = 31; final int prime = 31;
@ -1233,10 +1237,21 @@ public class SparseRealVector implements RealVector {
temp = Double.doubleToLongBits(epsilon); temp = Double.doubleToLongBits(epsilon);
result = prime * result + (int) (temp ^ (temp >>> 32)); result = prime * result + (int) (temp ^ (temp >>> 32));
result = prime * result + virtualSize; result = prime * result + virtualSize;
Iterator iter = entries.iterator();
while (iter.hasNext()) {
iter.advance();
temp = Double.doubleToLongBits(iter.value());
result = prime * result + (int) (temp ^ (temp >>32));
}
return result; return result;
} }
/** {@inheritDoc} */ /**
* <p> Implementation Note: This performs an exact comparison, and as a result
* it is possible for {@code a.subtract(b}} to be the zero vector, while
* {@code a.equals(b) == false}.</p>
* {@inheritDoc}
*/
@Override @Override
public boolean equals(Object obj) { public boolean equals(Object obj) {
if (this == obj) { if (this == obj) {
@ -1259,16 +1274,16 @@ public class SparseRealVector implements RealVector {
Iterator iter = entries.iterator(); Iterator iter = entries.iterator();
while (iter.hasNext()) { while (iter.hasNext()) {
iter.advance(); iter.advance();
double test = iter.value() - other.getEntry(iter.key()); double test = other.getEntry(iter.key());
if (Math.abs(test) > epsilon) { if (Double.doubleToLongBits(test) != Double.doubleToLongBits(iter.value())) {
return false; return false;
} }
} }
iter = other.getEntries().iterator(); iter = other.getEntries().iterator();
while (iter.hasNext()) { while (iter.hasNext()) {
iter.advance(); iter.advance();
double test = iter.value() - getEntry(iter.key()); double test = iter.value();
if (!isZero(test)) { if (Double.doubleToLongBits(test) != Double.doubleToLongBits(iter.value())) {
return false; return false;
} }
} }