/**
* Returns the selection array or vector.
*
* <p>The selSizes array contains sizes of the selectors (number of elements that will be
* returned by it). The idx array contains the indices returned by the selectors (that is the
* indices used to compute the source offset).
*
* <p>The selIdx array contains the position in the selector (when this is equal to the selector
* size the selector has overflown).
*/
public Object execute(RArray source, boolean drop, int exact) throws UnexpectedResultException {
int[] sourceDim = source.dimensions();
boolean mayHaveNA = Selector.initialize(offsets, selectorVals, sourceDim, selSizes, ast);
int[] destDim = Selector.calculateDestinationDimensions(selSizes, !subset || drop);
int destSize = Selector.calculateSizeFromSelectorSizes(selSizes);
RArray dest = Utils.createArray(source, destSize, destDim, null, null); // drop attributes
if (destSize == 0) {
return dest;
}
int offset = 0;
for (; ; ) {
int sourceOffset = offsets[0];
if (sourceOffset == RInt.NA) {
Utils.setNA(dest, offset);
} else {
dest.set(offset, source.getRef(sourceOffset));
}
offset++;
if (offset < destSize) {
if (!mayHaveNA) {
Selector.advanceNoNA(offsets, sourceDim, selectorVals, ast);
} else {
Selector.advance(offsets, sourceDim, selectorVals, ast);
}
} else {
break;
}
}
return dest;
}
