def main():
args = parse_args()
with open(args.dest_file_path, 'wb') as dest_file_obj:
data_gen = slice_file(
open_raw_data(args.source_file_path),
slice(args.slice_start, args.slice_stop),
words_to_read=args.words_to_read,
buffer_size=args.buffer_size,
)
for data in data_gen:
dest_file_obj.write(data)
def copy_file_part(src_path, percent_start=0, percent_stop=100):
'''
Copies percentage of the source path to a new destination file. If source
is compressed, output is read out into a decompressed file.
src_path can be either a zip (.SAC), bz2 or uncompressed data file
NOTE: Reads data into memory
TODO: Move to flightdatautilities.filesystem_tools ?
'''
from flightdatautilities.filesystem_tools import open_raw_data
ext = '_%d-%d.dat' % (percent_start, percent_stop)
dest_path = os.path.splitext(src_path)[0] + ext
if os.path.isfile(dest_path) and os.path.getsize(dest_path):
print 'Partial file already exists; using: %s' % dest_path
return dest_path
try:
src = open_raw_data(src_path)
src.seek(0, 2)
size = src.tell()
src.seek(0)
offset = int(percent_start * size / 100.0)
if offset % 2:
offset += 1 # make sure the start is even
read_end = int(percent_stop * size / 100.0)
amount = read_end - offset
if amount % 2:
amount -= 1 # make multiple of np.short (2 bytes)
src.seek(offset)
data = src.read(amount)
finally:
src.close()
with open(dest_path, 'wb') as dest:
dest.write(data)
return dest_path
