Source code for qcodes.utils.magic

from IPython.core.magic import Magics, magics_class, line_cell_magic

[docs]@magics_class class QCoDeSMagic(Magics): """Magics related to code management (loading, saving, editing, ...).""" def __init__(self, *args, **kwargs): """ Setup Magic. All args and kwargs are passed to super class. """ self._knowntemps = set() super().__init__(*args, **kwargs)
[docs] @line_cell_magic def measurement(self, line, cell=None): """ Create ``qcodes.Loop`` measurement mimicking Python ``for`` syntax via iPython magic. Upon execution of a notebook cell, the code is transformed from the for loop structure to a QCoDeS Loop before being executed. Can be run by having ``%%measurement`` in the first line of a cell, followed by the measurement name (see below for an example). The for loop syntax differs slightly from a Python ``for`` loop, as it uses ``for {iterable}`` instead of ``for {element} in {iterable}``. The reason is that ``{element}`` cannot be accessed (yet) in QCoDeS loops. Comments (#) are ignored in the loop. Any code after the loop will also be run, if separated by a blank line from the loop. The Loop object is by default stored in a variable named ``loop``, and the dataset in ``data``, and these can be overridden using options. Must be run in a Jupyter Notebook. Delays can be provided in a loop by adding ``-d {delay}`` after ``for``. The following options can be passed along with the measurement name (e.g. ``%%measurement -px -d data_name {measurement_name})``:: -p : print transformed code -x : Do not execute code -d <dataset_name> : Use custom name for dataset -l <loop_name> : Use custom name for Loop An example for a loop cell is as follows:: %%measurement {-options} {measurement_name} for {sweep_vals}: {measure_parameter1} {measure_parameter2} for -d 1 {sweep_vals2}: {measure_parameter3} ... which will be internally transformed to:: import qcodes loop = qcodes.Loop({sweep_vals}).each( {measure_parameter1}, {measure_parameter2}, qcodes.Loop({sweep_vals2}, delay=1).each( {measure_parameter3})) data = loop.get_data_set(name={measurement_name}) ... An explicit example of the line ``for {sweep_vals}:`` could be ``for sweep_parameter.sweep(0, 42, step=1):`` """ if cell is None: # No loop provided, print documentation print(self.measurement.__doc__) return # Parse line, get measurement name and any possible options options, msmt_name = self.parse_options(line, 'pd:l:x') data_name = options.get('d', 'data') loop_name = options.get('l', 'loop') lines = cell.splitlines() assert lines[0][:3] == 'for', "Measurement must start with for loop" contents = f'import qcodes\n{loop_name} = ' previous_level = 0 for k, line in enumerate(lines): line, level = line.lstrip(), int((len(line)-len(line.lstrip())) / 4) if not line: # Empty line, end of loop break elif line[0] == '#': # Ignore comment continue else: line_representation = ' ' * level * 4 if level < previous_level: # Exiting inner loop, close bracket line_representation += '),' * (previous_level - level) line_representation += '\n' + ' ' * level * 4 if line[:3] == 'for': # New loop for_opts, for_code = self.parse_options(line[4:-1], 'd:') if 'd' in for_opts: # Delay option provided line_representation += ('qcodes.Loop({}, ' 'delay={}).each(\n' ''.format(for_code, for_opts["d"])) else: line_representation += ('qcodes.Loop({}).each(\n' ''.format(for_code)) else: # Action in current loop line_representation += f'{line},\n' contents += line_representation # Remember level for next iteration (might exit inner loop) previous_level = level # Add closing brackets for any remaining loops contents += ')' * previous_level + '\n' # Add dataset contents += "{} = {}.get_data_set(name='{}')".format(data_name, loop_name, msmt_name) for line in lines[k+1:]: contents += '\n' + line if 'p' in options: print(contents) if 'x' not in options: # Execute contents self.shell.run_cell(contents, store_history=True, silent=True)
[docs]def register_magic_class(cls=QCoDeSMagic, magic_commands=True): """ Registers a iPython magic class. Args: cls: Magic class to register. magic_commands (List): List of magic commands within the class to register. If not specified, all magic commands are registered. """ ip = get_ipython() if ip is None: raise RuntimeError('No iPython shell found') else: if magic_commands is not True: # filter out any magic commands that are not in magic_commands cls.magics = {line_cell: {key: val for key, val in magics.items() if key in magic_commands} for line_cell, magics in cls.magics.items()} ip.magics_manager.register(cls)