rdrecord: allow smooth_frames=False for multi-segment records.

When reading a multi-segment, multi-frequency record, we want to have the option of reading each signal at its original sampling frequency, which requires using smooth_frames=False. Previously this simply wasn't allowed, either with or without multi-to-single conversion. To do this, we need to ensure each segment is loaded in the appropriate (smooth or non-smooth) mode (which formerly would have failed if certain segments *didn't* contain multiple samples per frame.) After loading the segments, we must invoke multi_to_single, if desired, in the appropriate mode.

Author: Benjamin Moody

wfdb/io/record.py

@@ -412,11 +412,6 @@ def check_read_inputs(self, sampfrom, sampto, channels, physical,
  if physical and return_res == 8:
  raise ValueError("return_res must be one of the following when physical is True: 64, 32, 16")
 
- # Cannot expand multiple samples/frame for multi-segment records
- if isinstance(self, MultiRecord):
- if not smooth_frames:
- raise ValueError('This package version cannot expand all samples when reading multi-segment records. Must enable frame smoothing.')
-
 
  def _adjust_datetime(self, sampfrom):
  """
@@ -3658,7 +3653,7 @@ def rdrecord(record_name, sampfrom=0, sampto=None, channels=None,
  os.path.join(dir_name, record.seg_name[seg_num]),
  sampfrom=seg_ranges[i][0], sampto=seg_ranges[i][1],
  channels=seg_channels[i], physical=physical, pn_dir=pn_dir,
- return_res=return_res)
+ smooth_frames=smooth_frames, return_res=return_res)
 
  # Arrange the fields of the layout specification segment, and
  # the overall object, to reflect user input.
@@ -3669,6 +3664,7 @@ def rdrecord(record_name, sampfrom=0, sampto=None, channels=None,
  # Convert object into a single segment Record object
  if m2s:
  record = record.multi_to_single(physical=physical,
+ expanded=(not smooth_frames),
  return_res=return_res)
 
  # Perform dtype conversion if necessary