Docs/params

qcodes/__init__.py

@@ -59,7 +59,14 @@
 from qcodes.instrument.mock import MockInstrument, MockModel
 
 from qcodes.instrument.function import Function
-from qcodes.instrument.parameter import Parameter, StandardParameter, combine, CombinedParameter
+from qcodes.instrument.parameter import (
+    Parameter,
+    ArrayParameter,
+    MultiParameter,
+    StandardParameter,
+    ManualParameter,
+    combine,
+    CombinedParameter)
 from qcodes.instrument.sweep_values import SweepFixedValues, SweepValues
 
 from qcodes.utils import validators

qcodes/data/data_array.py

@@ -1,7 +1,7 @@
 import numpy as np
 import collections
 
-from qcodes.utils.helpers import DelegateAttributes, full_class
+from qcodes.utils.helpers import DelegateAttributes, full_class, warn_units
 
 
 class DataArray(DelegateAttributes):
@@ -29,7 +29,7 @@ class DataArray(DelegateAttributes):
     Args:
         parameter (Optional[Parameter]): The parameter whose values will
             populate this array, if any. Will copy ``name``, ``full_name``,
-            ``label``, ``units``, and ``snapshot`` from here unless you
+            ``label``, ``unit``, and ``snapshot`` from here unless you
             provide them explicitly.
 
         name (Optional[str]): The short name of this array.
@@ -68,7 +68,9 @@ class DataArray(DelegateAttributes):
             handle converting this to array_id internally (maybe it
             already does?)
 
-        units (Optional[str]): The units of the values stored in this array.
+        unit (Optional[str]): The unit of the values stored in this array.
+
+        units (Optional[str]): DEPRECATED, redirects to ``unit``.
 
         is_setpoint (bool): True if this is a setpoint array, False if it
             is measured. Default False.
@@ -84,7 +86,7 @@ class DataArray(DelegateAttributes):
         'array_id',
         'name',
         'shape',
-        'units',
+        'unit',
         'label',
         'action_indices',
         'is_setpoint')
@@ -94,7 +96,7 @@ class DataArray(DelegateAttributes):
     COPY_ATTRS_FROM_INPUT = (
         'name',
         'label',
-        'units')
+        'unit')
 
     # keys in the parameter snapshot to omit from our snapshot
     SNAP_OMIT_KEYS = (
@@ -108,13 +110,17 @@ class DataArray(DelegateAttributes):
 
     def __init__(self, parameter=None, name=None, full_name=None, label=None,
                  snapshot=None, array_id=None, set_arrays=(), shape=None,
-                 action_indices=(), units=None, is_setpoint=False,
+                 action_indices=(), unit=None, units=None, is_setpoint=False,
                  preset_data=None):
         self.name = name
         self.full_name = full_name or name
         self.label = label
         self.shape = shape
-        self.units = units
+        if units is not None:
+            warn_units('DataArray', self)
+            if unit is None:
+                unit = units
+        self.unit = unit
         self.array_id = array_id
         self.is_setpoint = is_setpoint
         self.action_indices = action_indices
@@ -518,3 +524,8 @@ def fraction_complete(self):
             last_index = max(last_index, self.synced_index)
 
         return (last_index + 1) / self.ndarray.size
+
+    @property
+    def units(self):
+        warn_units('DataArray', self)
+        return self.unit

qcodes/data/data_set.py

@@ -283,7 +283,7 @@ def __init__(self, location=None, mode=DataMode.LOCAL, arrays=None,
 
         self.metadata = {}
 
-        self.arrays = {}
+        self.arrays = _PrettyPrintDict()
         if arrays:
             self.action_id_map = self._clean_array_ids(arrays)
             for array in arrays:
@@ -864,3 +864,18 @@ def __repr__(self):
             out += out_template.format(info=arr_info_i, lens=column_lengths)
 
         return out
+
+
+class _PrettyPrintDict(dict):
+    """
+    simple wrapper for a dict to repr its items on separate lines
+    with a bit of indentation
+    """
+    def __repr__(self):
+        body = '\n  '.join([repr(k) + ': ' + self._indent(repr(v))
+                            for k, v in self.items()])
+        return '{\n  ' + body + '\n}'
+
+    def _indent(self, s):
+        lines = s.split('\n')
+        return '\n    '.join(lines)

qcodes/data/hdf5_format.py

@@ -62,7 +62,13 @@ def read(self, data_set, location=None):
             # write ensures these attributes always exist
             name = dat_arr.attrs['name'].decode()
             label = dat_arr.attrs['label'].decode()
-            units = dat_arr.attrs['units'].decode()
+
+            # get unit from units if no unit field, for backward compatibility
+            if 'unit' in dat_arr.attrs:
+                unit = dat_arr.attrs['unit'].decode()
+            else:
+                unit = dat_arr.attrs['units'].decode()
+
             is_setpoint = str_to_bool(dat_arr.attrs['is_setpoint'].decode())
             # if not is_setpoint:
             set_arrays = dat_arr.attrs['set_arrays']
@@ -75,15 +81,15 @@ def read(self, data_set, location=None):
             if array_id not in data_set.arrays.keys():  # create new array
                 d_array = DataArray(
                     name=name, array_id=array_id, label=label, parameter=None,
-                    units=units,
+                    unit=unit,
                     is_setpoint=is_setpoint, set_arrays=(),
                     preset_data=vals)
                 data_set.add_array(d_array)
             else:  # update existing array with extracted values
                 d_array = data_set.arrays[array_id]
                 d_array.name = name
                 d_array.label = label
-                d_array.units = units
+                d_array.unit = unit
                 d_array.is_setpoint = is_setpoint
                 d_array.ndarray = vals
                 d_array.shape = dat_arr.attrs['shape']
@@ -196,34 +202,26 @@ def _create_dataarray_dset(self, array, group):
         group:  group in the hdf5 file where the dset will be created
 
         creates a hdf5 datasaset that represents the data array.
-
-        note that the attribute "units" is used for shape determination
-        in the case of tuple-like variables.
         '''
         # Check for empty meta attributes, use array_id if name and/or label
         # is not specified
         if array.label is not None:
             label = array.label
         else:
             label = array.array_id
+
         if array.name is not None:
             name = array.name
         else:
             name = array.array_id
-        if array.units is None:
-            array.units = ['']  # used for shape determination
-        units = array.units
+
         # Create the hdf5 dataset
-        if isinstance(units, str):
-            n_cols = 1
-        else:
-            n_cols = len(array.units)
         dset = group.create_dataset(
-            array.array_id, (0, n_cols),
-            maxshape=(None, n_cols))
+            array.array_id, (0, 1),
+            maxshape=(None, 1))
         dset.attrs['label'] = _encode_to_utf8(str(label))
         dset.attrs['name'] = _encode_to_utf8(str(name))
-        dset.attrs['units'] = _encode_to_utf8(str(units))
+        dset.attrs['unit'] = _encode_to_utf8(str(array.unit or ''))
         dset.attrs['is_setpoint'] = _encode_to_utf8(str(array.is_setpoint))
 
         set_arrays = []

qcodes/instrument/mock.py

@@ -3,7 +3,7 @@
 from datetime import datetime
 
 from .base import Instrument
-from .parameter import Parameter
+from .parameter import MultiParameter
 from qcodes import Loop
 from qcodes.data.data_array import DataArray
 from qcodes.process.server import ServerManager, BaseServer
@@ -283,22 +283,21 @@ def _delattr(self, attr):
         """
         self.ask('method_call', 'delattr', attr)
 
-class ArrayGetter(Parameter):
+class ArrayGetter(MultiParameter):
     """
     Example parameter that just returns a single array
 
-    TODO: in theory you can make this same Parameter with
+    TODO: in theory you can make this an ArrayParameter with
     name, label & shape (instead of names, labels & shapes) and altered
     setpoints (not wrapped in an extra tuple) and this mostly works,
     but when run in a loop it doesn't propagate setpoints to the
-    DataSet. We could track down this bug, but perhaps a better solution
-    would be to only support the simplest and the most complex Parameter
-    forms (ie cases 1 and 5 in the Parameter docstring) and do away with
-    the intermediate forms that make everything more confusing.
+    DataSet. This is a bug
     """
     def __init__(self, measured_param, sweep_values, delay):
         name = measured_param.name
-        super().__init__(names=(name,))
+        super().__init__(names=(name,),
+                         shapes=((len(sweep_values),),),
+                         name=name)
         self._instrument = getattr(measured_param, '_instrument', None)
         self.measured_param = measured_param
         self.sweep_values = sweep_values