Function qr

src/backend/opencl/cpu/cpu_qr.cpp:59–88

template<typename T>
void qr(Array<T> &q, Array<T> &r, Array<T> &t, const Array<T> &in) {
    dim4 iDims = in.dims();
    int M      = iDims[0];
    int N      = iDims[1];

    const dim4 NullShape(0, 0, 0, 0);

    dim4 endPadding(M - iDims[0], max(M, N) - iDims[1], 0, 0);
    q = (endPadding == NullShape
             ? copyArray(in)
             : padArrayBorders(in, NullShape, endPadding, AF_PAD_ZERO));
    q.resetDims(iDims);
    t = qr_inplace(q);

    // SPLIT into q and r
    dim4 rdims(M, N);
    r = createEmptyArray<T>(rdims);

    mapped_ptr<T> qPtr = q.getMappedPtr();
    mapped_ptr<T> rPtr = r.getMappedPtr();
    mapped_ptr<T> tPtr = t.getMappedPtr();

    triangle<T, true, false>(rPtr.get(), qPtr.get(), rdims, r.strides(),
                             q.strides());

    gqr_func<T>()(AF_LAPACK_COL_MAJOR, M, M, min(M, N), qPtr.get(),
                  q.strides()[1], tPtr.get());

    q.resetDims(dim4(M, M));
}

template<typename T>
Array<T> qr_inplace(Array<T> &in) {