Function _get_fields_and_offsets

numpy/lib/recfunctions.py:853–888

Returns a flat list of (dtype, count, offset) tuples of all the scalar fields in the dtype "dt", including nested fields, in left to right order.

(dt, offset=0)

    return np.dtype((a.type, dt))

def _get_fields_and_offsets(dt, offset=0):
    """
    Returns a flat list of (dtype, count, offset) tuples of all the
    scalar fields in the dtype "dt", including nested fields, in left
    to right order.
    """

    # counts up elements in subarrays, including nested subarrays, and returns
    # base dtype and count
    def count_elem(dt):
        count = 1
        while dt.shape != ():
            for size in dt.shape:
                count *= size
            dt = dt.base
        return dt, count

    fields = []
    for name in dt.names:
        field = dt.fields[name]
        f_dt, f_offset = field[0], field[1]
        f_dt, n = count_elem(f_dt)

        if f_dt.names is None:
            fields.append((np.dtype((f_dt, (n,))), n, f_offset + offset))
        else:
            subfields = _get_fields_and_offsets(f_dt, f_offset + offset)
            size = f_dt.itemsize

            for i in range(n):
                if i == 0:
                    # optimization: avoid list comprehension if no subarray
                    fields.extend(subfields)
                else:
                    fields.extend([(d, c, o + i * size) for d, c, o in subfields])
    return fields

def _common_stride(offsets, counts, itemsize):
    """