import collections
import os
[docs]def ensure_dir(dirname):
"""
Ensure directory exists.
Roughly equivalent to `mkdir -p`
"""
if not os.path.isdir(dirname):
os.makedirs(dirname)
[docs]def derive_out_path(in_paths, out_dir, out_extension='',
strip_in_extension=True,
out_prefix=None):
"""
Derives an 'output' path given some 'input' paths and an output directory.
In the simple case that only a single path is supplied, this is
simply the pathname resulting from replacing extension suffix and moving
dir, e.g.
``input_dir/basename.in`` -> ``output_dir/basename.out``
If the out_dir is specified as 'None' then it is assumed that the
new file should be located in the same directory as the first
input path.
In the case that multiple input paths are supplied, their basenames
are concatenated, e.g.
``in_dir/base1.in`` + ``in_dir/base2.in``
-> ``out_dir/base1_base2.out``
If the resulting output path is identical to any input path, this
raises an exception.
NB the extension should be supplied including the '.' prefix.
"""
in_paths = listify(in_paths)
if out_dir is None:
out_dir = os.path.dirname(in_paths[0])
in_basenames = [os.path.basename(ip) for ip in in_paths]
if strip_in_extension:
in_basenames = [ os.path.splitext(bn)[0] for bn in in_basenames ]
out_basename = '_'.join(in_basenames)
if out_prefix:
out_basename = out_prefix+out_basename
out_path = os.path.join(out_dir, out_basename + out_extension)
for ip in in_paths:
if os.path.abspath(out_path) == os.path.abspath(ip):
raise RuntimeError(
'Specified path derivation results in output overwriting input!')
return out_path
[docs]def save_script(script, filename):
"""Save a list of casa commands as a text file"""
with open(filename, 'w') as fp:
fp.write('\n'.join(script))
[docs]def byteify(input):
"""
Co-erce unicode to 'bytestring'
(or string containing unicode, or dict containing unicode)
Useful when e.g. importing filenames from JSON
(CASA sometimes breaks if passed Unicode strings.)
cf http://stackoverflow.com/a/13105359/725650
"""
if isinstance(input, dict):
return {byteify(key):byteify(value) for key,value in input.iteritems()}
elif isinstance(input, list):
return [byteify(element) for element in input]
elif isinstance(input, unicode):
return input.encode('utf-8')
else:
return input
[docs]def listify(x):
"""
Ensure x is a (non-string) iterable; if not, enclose in a list.
Returns:
x or [x], accordingly.
"""
if isinstance(x, basestring):
return [x]
elif isinstance(x, collections.Iterable):
return x
else:
return [x]