public static SparseIntArray histogram(int[] vector, int W) {
final SparseIntArray hist = new SparseIntArray(W);
for (int i : vector) {
hist.inc(i);
}
return hist;
}
public static SparseIntArray fromBinary(InputStream stream, int W) throws IOException {
final DataInputStream dis = new DataInputStream(stream);
final SparseIntArray arr = new SparseIntArray(W);
while (dis.available() > 0) {
try {
arr.inc(dis.readInt());
} catch (EOFException x) {
break;
}
}
return arr;
}
public static SparseIntArray fromFrequencyString(String string, int n)
throws VectorFormatException {
final String[] entries = string.split("\\s+");
final SparseIntArray array = new SparseIntArray(n);
for (String entry : entries) {
try {
array.inc(Integer.parseInt(entry));
} catch (NumberFormatException x) {
throw new VectorFormatException(x);
}
}
return array;
}