private Array arr;

private Seq seq;

private boolean isSeq;

private boolean isBatch;

private static native long afLookup(long in, long index, int dim);

private static native void afCopy(long dst, long src, int ndims, Object idx0, Object idx1,

Object idx2, Object idx3);

public Index() {

seq = ArrayFire.SPAN;

isSeq = true;

isBatch = false;

}

public Index(int idx) throws Exception {

seq = new Seq(idx, idx, 1);

isSeq = true;

isBatch = false;

}

public Index(final Seq seq) throws Exception {

this.seq = new Seq(seq);

isSeq = true;

isBatch = this.seq.gfor;

}

public Index(final Array idx) throws Exception {

arr = idx.isBool() ? Algorithm.where(idx) : new Array(idx.ref);

isSeq = false;

isBatch = false;

}

public Index(final Index other) {

arr = new Array(other.arr.ref);

seq = new Seq(other.seq);

isSeq = other.isSeq;

isBatch = other.isBatch;

}

public long getArrayRef() {

return arr.ref;

}

public Object getSeq() {

return seq;

}

public boolean isSeq() {

return isSeq;

}

public boolean isBatch() {

return isBatch;

}

public boolean isSpan() {

return isSeq && seq == ArrayFire.SPAN;

}

static Array lookup(final Array in, final Array idx, int dim) throws Exception {

return new Array(afLookup(in.ref, idx.ref, dim));

}

static void copy(Array dst, final Array src, Index idx0, Index idx1,

Index idx2, Index idx3) throws Exception{

int ndims = Arrays.stream(dst.dims()).filter(x -> x > 1).toArray().length;

afCopy(dst.ref, src.ref, ndims, idx0, idx1, idx2, idx3);

}