calibcant/util.py

   1 # Copyright
   2
   3 """Useful utilites not related to calibration.
   4
   5 Currently just a framework for consistently saving/loading calibration
   6 data.
   7 """
   8
   9 import h5py as _h5py
  10
  11 from h5config.storage.hdf5 import HDF5_Storage as _HDF5_Storage
  12 from h5config.storage.hdf5 import h5_create_group as _h5_create_group
  13
  14
  15 from . import LOG as _LOG
  16
  17
  18 class SaveSpec (object):
  19     def __init__(self, item=None, relpath='/', key=None, config=False,
  20                  array=False, units=None, deviation=None):
  21         self.item = item
  22         self.relpath = relpath
  23         self.key = key
  24         self.config = config
  25         self.array = array
  26         self.units = units
  27         self.deviation = deviation
  28
  29 def save(filename=None, group='/', specs=tuple()):
  30     f = None
  31     storage = _HDF5_Storage()
  32     try:
  33         if isinstance(group, str):
  34             f = _h5py.File(filename, 'a')
  35             group = _h5_create_group(f, group)
  36         for spec in specs:
  37             if spec.item is None:
  38                 continue
  39             cwg = _h5_create_group(group, spec.relpath)
  40             if spec.config:
  41                 storage.save(config=spec.item, group=cwg)
  42                 continue
  43             assert spec.units, spec.item
  44             try:
  45                 del cwg['data']
  46             except KeyError:
  47                 pass
  48             try:
  49                 del cwg['units']
  50             except KeyError:
  51                 pass
  52             cwg['data'] = spec.item
  53             cwg['units'] = spec.units
  54             if spec.deviation is not None:
  55                 cwg['standard-deviation'] = spec.deviation
  56     finally:
  57         if f:
  58             f.close()
  59
  60 def load(filename=None, group='/', specs=tuple()):
  61     data = {}
  62     f = None
  63     storage = _HDF5_Storage()
  64     try:
  65         if isinstance(group, str):
  66             f = _h5py.File(filename, 'a')
  67             group = _h5_create_group(f, group)
  68         for spec in specs:
  69             try:
  70                 cwg = group[spec.relpath]
  71             except KeyError:
  72                 continue
  73             d = data
  74             for n in spec.key[:-1]:
  75                 if n not in d:
  76                     d[n] = {}
  77                 d = d[n]
  78             if spec.config:
  79                 d[spec.key[-1]] = spec.config(storage=_HDF5_Storage(group=cwg))
  80                 d[spec.key[-1]].load()
  81                 continue
  82             assert spec.units, spec.key
  83             try:
  84                 if spec.array:
  85                     d[spec.key[-1]] = cwg['data'][...]
  86                 else:
  87                     d[spec.key[-1]] = float(cwg['data'][...])
  88             except KeyError:
  89                 continue
  90             except TypeError, e:
  91                 _LOG.warn('while loading {} from {}: {}'.format(
  92                         spec.key, cwg['data'], e))
  93                 raise
  94             if spec.key[-1] in d:
  95                 units_ = cwg['units'][...]
  96                 assert units_ == spec.units, (units_, spec.units)
  97                 if spec.deviation is not None:
  98                     try:
  99                         d[spec.deviation] = float(
 100                             cwg['standard-deviation'][...])
 101                     except KeyError:
 102                         pass
 103     finally:
 104         if f:
 105             f.close()
 106     return data