General

class lantz.Driver(*args, **kw)

Base class for all drivers.

Params name:easy to remember identifier given to the instance for logging purposes
log(level, msg, *args, **kwargs)

Log with the integer severity ‘level’ on the logger corresponding to this instrument.

Parameters:
  • level – severity level for this event.
  • msg – message to be logged (can contain PEP3101 formatting codes)
log_critical(msg, *args, **kwargs)

Log with the severity ‘CRITICAL’ on the logger corresponding to this instrument.

Parameters:msg – message to be logged (can contain PEP3101 formatting codes)
log_debug(msg, *args, **kwargs)

Log with the severity ‘DEBUG’ on the logger corresponding to this instrument.

Parameters:msg – message to be logged (can contain PEP3101 formatting codes)
log_error(msg, *args, **kwargs)

Log with the severity ‘ERROR’ on the logger corresponding to this instrument.

Parameters:msg – message to be logged (can contain PEP3101 formatting codes)
log_info(msg, *args, **kwargs)

Log with the severity ‘INFO’ on the logger corresponding to this instrument.

Parameters:msg – message to be logged (can contain PEP3101 formatting codes)
log_warning(msg, *args, **kwargs)

Log with the severity ‘WARNING’ on the logger corresponding to this instrument.

Parameters:msg – message to be logged (can contain PEP3101 formatting codes)
recall(keys=None)

Return the last value seen for a feat or a collection of feats.

Parameters:keys (str, list, tuple, dict.) – a string or list of strings with the properties to refresh. Default None all properties. If keys is a string, returns the value. If keys is a list, returns a dictionary.
refresh(keys=None)

Refresh cache by reading values from the instrument.

Parameters:keys (str or list or tuple or dict) – a string or list of strings with the properties to refresh. Default None, meaning all properties. If keys is a string, returns the value. If keys is a list/tuple, returns a tuple. If keys is a dict, returns a dict.
refresh_async(keys=None, *, callback=None)

Asynchronous refresh cache by reading values from the instrument.

Parameters:keys (str or list or tuple or dict) – a string or list of strings with the properties to refresh Default None, meaning all properties. If keys is a string, returns the value. If keys is a list, returns a dictionary.
Return type:concurrent.future.
update(newstate=None, *, force=False, **kwargs)

Update driver.

Parameters:
  • newstate (dict.) – a dictionary containing the new driver state.
  • force – apply change even when the cache says it is not necessary.
  • force – boolean.
Raises:

ValueError if called with an empty dictionary.
update_async(newstate=None, *, force=False, callback=None, **kwargs)

Asynchronous update driver.

Parameters:
  • newstate (dict.) – driver state.
  • force (boolean.) – apply change even when the cache says it is not necessary.
  • callback (callable.) – Called when the update finishes.
Return type:

concurrent.future
Raises:

ValueError if called with an empty dictionary.
class lantz.Feat(fget=MISSING, fset=None, doc=None, *, values=None, units=None, limits=None, procs=None, read_once=False)

Pimped Python property for interfacing with instruments. Can be used as a decorator.

Processors can registered for each arguments to modify their values before they are passed to the body of the method. Two standard processors are defined: values and units and others can be given as callables in the procs parameter.

If a method contains multiple arguments, use a tuple. None can be used as do not change.

Parameters:
  • fget – getter function.
  • fset – setter function.
  • doc – docstring, if missing fget or fset docstring will be used.
  • values – A dictionary to map key to values. A set to restrict the values. If a list/tuple instead of a dict is given, the value is not changed but only tested to belong to the container.
  • units – Quantity or string that can be interpreted as units.
  • procs – Other callables to be applied to input arguments.
modifiers = None

instance: key: value

value = None

instance: value

class lantz.DictFeat(fget=MISSING, fset=None, doc=None, *, keys=None, **kwargs)

Pimped Python property with getitem access for interfacing with instruments. Can be used as a decorator.

Takes the same parameters as Feat, plus:

Parameters:keys – List/tuple restricts the keys to the specified ones.
class lantz.Action(func=None, *, values=None, units=None, limits=None, procs=None)

Wraps a Driver method with Lantz. Can be used as a decorator.

Processors can registered for each arguments to modify their values before they are passed to the body of the method. Two standard processors are defined: values and units and others can be given as callables in the procs parameter.

If a method contains multiple arguments, use a tuple. None can be used as do not change.

Parameters:
  • func – driver method to be wrapped.
  • values – A dictionary to values key to values. If a list/tuple instead of a dict is given, the value is not changed but only tested to belong to the container.
  • units – Quantity or string that can be interpreted as units.
  • procs – Other callables to be applied to input arguments.
modifiers = None

instance: key: value