qcodespp.measure

Classes

Module Contents

class qcodespp.measure.Measure(setpoints=None, parameters=None, use_threads=False, station=None, name=None, timer=False)

Bases: qcodes.metadatable.Metadatable

Class to create a DataSetPP from a single (non-looped) set of measured parameters.

Measure is used to measure a set of parameters at a single point in time. The typical use case is where the parameter(s)’s get function(s) return(s) an array, e.g. an oscilloscope trace, or a spectrum analyser trace. At init, you can provide the parameters to measure and (optionally) setpoints. If no parameters are provided, the default station.measure() is used. If no setpoints are provided, dummy setpoints are created for each dimension found in the parametersn (recommended, see below).

Measure.run() will execute the measurement, and return and save a DataSetPP

Examples:

Measure two parameters:

>>> station.set_measurement(array_param1, array_param2)
>>> data = Measure(name='Name for dataset filename').run()

Measure two parameters twice, changing some value in between:

>>> station.set_measurement(array_param1, array_param2)
>>> measure = Measure()
>>> data=measure.run(name='instrument parameter value = 0')
>>> instrument.some_parameter(1.0)  # Set some parameter to a value
>>> data=measure.run(name='instrument parameter value = 1')

Iteratively:

>>> station.set_measurement(array_param1, array_param2)
>>> measure = Measure()
>>> for i in range(10):
>>>     instrument.some_parameter(i)  # Set some parameter to a value
>>>     data=measure.run(name=f'iteration {i}')

Args:

parameters (Optional, Sequence[Parameter]): Sequence of gettable Parameters.: If no actions are provided, the default station.measure() is used.

name (Optional, str): String to send to the filename of the DataSet.

station (Optional, Station): The Station to use if not the default.

use_threads (Optional, bool): Use threading to parallelize getting parameters from instruments.

setpoints (Optional, Sequence[Parameter or Array]): sequence of setpoint arrays: use for the DataSetPP. Can be array(s) of values, or gettable Parameter(s). If not provided, dummy setpoints are created for each dimension found in the parameters. Providing a setpoint parameter may be useful if you measure a parameter that is considered the independent variable. e.g. time on an oscilloscope, or a voltage ramp on a source. live_plot and offline_plotting will then be able to plot the correct dependencies automatically. However; it can be tricky to get all the dimensions right, so in most instances it’s better to just pass all measured parameters to the parameters argument, and then plot whatever parameter against whatever other parameter manually.
timer (Optional, bool, default False): The default station.measure() includes a timer parameter, which is: useful for Loops but essentially useless here. If you really want it, set timer=True.

station

use_threads = False

setpoints = None

name = None

timer = False

actions = None

each(*actions)

Set the actions to be performed in this measurement.

Actions can be added during init, however this method is provided to make the Measure class look like a Loop, where actions are added with .each(), and it makes somehow sense gramatically.

Args:

actions: a sequence of actions to perform. Any action that is: valid in a Loop can be used here. If an action is a gettable Parameter, its output will be included in the DataSetPP. If no actions are provided, the default station.measure() is used.

run_temp(**kwargs): Wrapper to run this measurement as a temporary data set

run(name=None, params_to_plot=None, use_threads=None, quiet=False, station=None, publisher=None, **kwargs)

Run the actions in this measurement and return their data as a DataSetPP

Args:

params_to_plot: a list of parameters to plot once the measurement is done.: Can either be the DataArray objects, or the parameters themselves.
quiet (Optional[bool]): Set True to not print anything except: errors. Default False.
station (Optional[Station]): the Station this measurement: pertains to. Defaults to Station.default if one is defined. Only used to supply metadata.
use_threads (Optional[bool]): whether to parallelize get: operations using threads. Default False.

Other kwargs are passed along to data_set.new_data. The key ones are:

location (Optional[Union[str, False]]): the location of the: DataSetPP, a string whose meaning depends on formatter and io, or False to only keep in memory. May be a callable to provide automatic locations. If omitted, will use the default DataSetPP.location_provider
name (Optional[str]): if location is default or another provider: function, name is a string to add to location to make it more readable/meaningful to users
formatter (Optional[Formatter]): knows how to read and write the: file format. Default can be set in DataSetPP.default_formatter
io (Optional[io_manager]): knows how to connect to the storage: (disk vs cloud etc)

returns:

a DataSetPP object containing the results of the measurement

snapshot_base(update=False): Override this with the primary information for a subclass.