Ejemplo n.º 1
0
def _read_colormap_data_from_file(filename):
    if not os.path.exists(filename):
        filename = get_config_path(filename)
    ext = os.path.splitext(filename)[1]
    if ext in (".npy", ".npz"):
        file_content = np.load(filename)
        if ext == ".npz":
            # .npz is a collection
            # assume position list-like and get the first element
            file_content = file_content["arr_0"]
        return file_content
    # CSV
    return np.loadtxt(filename, delimiter=",")
Ejemplo n.º 2
0
def create_sections(structure):
    """Create file sections."""
    sections = {}
    format_fn = get_config_path("eps_avhrrl1b_6.5.xml")
    form = eps.XMLFormat(format_fn)
    for count, (rec_class, sub_class) in structure:
        try:
            the_dtype = form.dtype((rec_class, sub_class))
        except KeyError:
            continue
        item_size = the_dtype.itemsize + grh_dtype.itemsize
        the_dtype = np.dtype(grh_dtype.descr + the_dtype.descr)
        item = np.zeros(count, the_dtype)
        item['record_class'] = eps.record_class.index(rec_class)
        item['RECORD_SUBCLASS'] = sub_class
        item['RECORD_SIZE'] = item_size

        sections[(rec_class, sub_class)] = item
    return sections
Ejemplo n.º 3
0
def read_records(filename):
    """Read *filename* without scaling it afterwards."""
    format_fn = get_config_path("eps_avhrrl1b_6.5.xml")
    form = XMLFormat(format_fn)

    grh_dtype = np.dtype([("record_class", "|i1"), ("INSTRUMENT_GROUP", "|i1"),
                          ("RECORD_SUBCLASS", "|i1"),
                          ("RECORD_SUBCLASS_VERSION", "|i1"),
                          ("RECORD_SIZE", ">u4"), ("RECORD_START_TIME", "S6"),
                          ("RECORD_STOP_TIME", "S6")])

    max_lines = np.floor((CHUNK_SIZE**2) / 2048)

    dtypes = []
    cnt = 0
    counts = []
    classes = []
    prev = None
    with open(filename, "rb") as fdes:
        while True:
            grh = np.fromfile(fdes, grh_dtype, 1)
            if grh.size == 0:
                break
            rec_class = record_class[int(grh["record_class"])]
            sub_class = grh["RECORD_SUBCLASS"][0]

            expected_size = int(grh["RECORD_SIZE"])
            bare_size = expected_size - grh_dtype.itemsize
            try:
                the_type = form.dtype((rec_class, sub_class))
                # the_descr = grh_dtype.descr + the_type.descr
            except KeyError:
                the_type = np.dtype([('unknown', 'V%d' % bare_size)])
            the_descr = grh_dtype.descr + the_type.descr
            the_type = np.dtype(the_descr)
            if the_type.itemsize < expected_size:
                padding = [('unknown%d' % cnt,
                            'V%d' % (expected_size - the_type.itemsize))]
                cnt += 1
                the_descr += padding
            new_dtype = np.dtype(the_descr)
            key = (rec_class, sub_class)
            if key == prev:
                counts[-1] += 1
            else:
                dtypes.append(new_dtype)
                counts.append(1)
                classes.append(key)
                prev = key
            fdes.seek(expected_size - grh_dtype.itemsize, 1)

        sections = {}
        offset = 0
        for dtype, count, rec_class in zip(dtypes, counts, classes):
            fdes.seek(offset)
            if rec_class == ('mdr', 2):
                record = da.from_array(np.memmap(fdes,
                                                 mode='r',
                                                 dtype=dtype,
                                                 shape=count,
                                                 offset=offset),
                                       chunks=(max_lines, ))
            else:
                record = np.fromfile(fdes, dtype=dtype, count=count)
            offset += dtype.itemsize * count
            if rec_class in sections:
                logger.debug('Multiple records for ', str(rec_class))
                sections[rec_class] = np.hstack((sections[rec_class], record))
            else:
                sections[rec_class] = record

    return sections, form