Source code for src.Instrument

# -*- coding: utf-8 -*-
"""The baseline for loading a scanning instrument

Each instrument will have its own module that declares a class
inheriting from ScanningInstrument.  The abstract base class is used
to ensure that the derived classes define the necessary methods to run
any generic scripts.

"""

from abc import ABCMeta, abstractmethod, abstractproperty
from logging import info, warning
from six import add_metaclass
from .genie import gen


[docs]@add_metaclass(ABCMeta) # pylint: disable=too-many-public-methods class ScanningInstrument(object): """The base class for scanning measurement instruments.""" _dae_mode = None _detector_lock = False title_footer = "" measurement_type = "sans" _TIMINGS = ["uamps", "frames", "seconds", "minutes", "hours"] def __init__(self): self.setup_sans = self.setup_dae_event self.setup_trans = self.setup_dae_transmission
[docs] def set_default_dae(self, mode=None, trans=False): """Set the default DAE mode for SANS or TRANS measuremnts. Parameters ---------- mode : str or function If the mode is a function, call that function to set the DAE mode. If the mode is a string, call the function whose name is "setup_dae_" followed by that string. trans : bool If true, set the default transmission instead of the default SANS mode. """ if mode is None: pass elif isinstance(mode, str): self.set_default_dae( getattr(self, "setup_dae_"+mode), trans) else: if trans: self.setup_trans = mode else: self.setup_sans = mode
@property def TIMINGS(self): # pylint: disable=invalid-name """The list of valid waitfor keywords.""" return self._TIMINGS # pragma: no cover
[docs] def sanitised_timings(self, kwargs): """Include only the keyword arguments for run timings. Parameters ---------- kwargs : dict A dictionary of keyword arguments Returns ------- dict Keyword arguments accepted by gen.waitfor """ result = {} for k in self.TIMINGS: if k in kwargs: result[k] = kwargs[k] return result
@staticmethod def _generic_scan(detector, spectra, wiring, tcbs): """A utility class for setting up dae states On its own, it's not particularly useful, but letting subclasses provide default parameters simplifies creating new dae states. """ gen.change(nperiods=1) gen.change_start() gen.change_tables(detector=detector) gen.change_tables(spectra=spectra) gen.change_tables(wiring=wiring) for tcb in tcbs: gen.change_tcb(**tcb) gen.change_finish() @abstractproperty def _poslist(self): # pragma: no cover """The list of named positions that the instrument can run through in the sample changer""" return [] @staticmethod def _needs_setup(): if gen.get_runstate() != "SETUP": # pragma: no cover raise RuntimeError("Cannot start a measurement in a measurement")
[docs] @abstractmethod def set_measurement_type(self, value): # pragma: no cover """Set the measurement type in the journal. Parameters ========== value : str The new measurement type This function should perform no physical changes to the beamline. The only change should be in the MEASUREMENT:TYPE value stored in the journal for the next run, which should be set to the new value. """ pass # pragma: no cover
[docs] @abstractmethod def set_measurement_label(self, value): # pragma: no cover """Set the sample label in the journal. Parameters ========== value : str The new sample label This function should perform no physical changes to the beamline. The only change should be in the MEASUREMENT:LABEL value stored in the journal for the next run, which should be set to the new value. """ pass # pragma: no cover
[docs] @abstractmethod def set_measurement_id(self, value): # pragma: no cover """Set the measurement id in the journal. Parameters ========== value : str The new id This function should perform no physical changes to the beamline. The only change should be in the MEASUREMENT:ID value stored in the journal for the next run, which should be set to the new value. """ pass
[docs] @abstractmethod def setup_dae_scanning(self): # pragma: no cover """Set the wiring tables for a scan""" pass
[docs] @abstractmethod def setup_dae_nr(self): # pragma: no cover """Set the wiring tables for a neutron reflectivity measurement""" pass
[docs] @abstractmethod def setup_dae_nrscanning(self): # pragma: no cover """Set the wiring tables for performing scans during neutron reflectivity""" pass
[docs] @abstractmethod def setup_dae_event(self): # pragma: no cover """Set the wiring tables for event mode""" pass
[docs] @abstractmethod def setup_dae_histogram(self): # pragma: no cover """Set the wiring tables for histogram mode""" pass
[docs] @abstractmethod def setup_dae_transmission(self): # pragma: no cover """Set the wiring tables for a transmission measurement""" pass
[docs] @abstractmethod def setup_dae_bsalignment(self): # pragma: no cover """Configure wiring tables for beamstop alignment.""" pass
def _configure_sans_custom(self): """The specific actions required by the instrument to run a SANS measurement (e.g. remove the monitor from the beam). This is a no-op for the default instrument but can be overwritten by other instruments to perform any actions they need to put the instrument into SANS mode. """ pass def _configure_trans_custom(self): """The specific actions required by the instrument to run a SANS measurement (e.g. remove the monitor from the beam). This is a no-op for the default instrument but can be overwritten by other instruments to perform any actions they need to put the instrument into SANS mode. """ pass def _begin(self, *args, **kwargs): """Start a measurement.""" if self._dae_mode and hasattr(self, "_begin_"+self._dae_mode): getattr(self, "_begin_"+self._dae_mode)(*args, **kwargs) else: gen.begin(*args, **kwargs) def _end(self): """End a measurement.""" if self._dae_mode and hasattr(self, "_end_"+self._dae_mode): getattr(self, "_end_"+self._dae_mode)() # pragma: no cover else: gen.end() def _waitfor(self, **kwargs): """Await the user's desired statistics.""" if self._dae_mode and hasattr(self, "_waitfor_"+self._dae_mode): getattr(self, "_waitfor_"+self._dae_mode)(**kwargs) else: gen.waitfor(**kwargs)
[docs] @staticmethod @abstractmethod def set_aperature(size): # pragma: no cover """Set the beam aperature to the desired size Parameters ---------- size : str The aperature size. e.g. "Small" or "Medium" A blank string (the default value) results in the aperature not being changed.""" pass
[docs] def detector_lock(self, state=None): """Query or activate the detector lock Parameters ========== state : bool or None If None, return the current lock state. Otherwise, set the new lock state Returns ======= The current lock state as a bool Locking the detector prevents turning the detector on or off and bypasses the detector checks. """ if state is not None: self._detector_lock = state return self._detector_lock
[docs] def detector_on(self, powered=None, delay=True): """Query and set the detector's electrical state. Parameters ---------- on : bool or None If None, then return the detector's current state. If True, turn the detector on. If False, turn the detector off. delay : bool If changing the detector state, whether to wait for the detector to finish warming up or powering down before continuing the script. Returns : bool If the detector is currently on """ if powered is not None: if self.detector_lock(): raise RuntimeError("The instrument scientist has locked the" " detector state") if powered is True: self._detector_turn_on(delay=delay) else: self._detector_turn_off(delay=delay) return self._detector_is_on()
@staticmethod @abstractmethod def _detector_is_on(): # pragma: no cover """Determine the current state of the detector. Returns ------- bool True if the detector is powered up. """ return False @staticmethod @abstractmethod def _detector_turn_on(delay=True): # pragma: no cover """Power on the detector Parameters ========== delay : bool Wait for the detector to warm up before continuing """ return False @staticmethod @abstractmethod def _detector_turn_off(delay=True): # pragma: no cover """Remove detector power Parameters ========== delay : bool Wait for the detector to cool down before continuing """ return False
[docs] def check_move_pos(self, pos): """Check whether the position is valid and return True or False Parameters ---------- pos : str The sample changer position """ if pos.upper() not in self._poslist: warning("Error in script, position {} does not exist".format(pos)) return False return True
def _setup_measurement(self, trans, blank): """Perform all of the software setup for a measurement Parameters ========== trans : bool Is this a transmission measurement blank : bool Is this a measurement on a sample blank """ if trans: if blank: self.set_measurement_type("blank_transmission") else: self.set_measurement_type("transmission") self.setup_trans() self._configure_trans_custom() else: if blank: self.set_measurement_type("blank") else: self.set_measurement_type(self.measurement_type) self.setup_sans() self._configure_sans_custom()
[docs] def measure(self, title, pos=None, thickness=1.0, trans=False, dae=None, blank=False, aperature="", **kwargs): """Take a sample measurement. Parameters ========== title : str The title for the measurement. This is the only required parameter. pos The sample position. This can be a string with the name of a sample position or it can be a function which moves the detector into the desired position. If left undefined, the instrument will take the measurement in its current position. thickness : float The thickness of the sample in millimeters. The default is 1mm. trans : bool Whether to perform a transmission run instead of a sans run. dae : str or func This option allows setting the default dae mode. It takes a string that contains the name of the DAE mode to be used as the new default. For example, >>> measure("Test", frames=10, dae="event") Is equivalent to >>> set_default_dae(setup_dae_event) >>> measure("Test", frames=10) If dae is a function, then the function is set to the default >>> measure("Test", frames=10, dae=foo) Is equivalent to >>> set_default_dae(foo) >>> measure("Test", frames=10) To get a full list of the supported dae modes, run >>> enumerate_dae() aperature : str The aperature size. e.g. "Small" or "Medium" A blank string (the default value) results in the aperature not being changed. blank : bool If this sample should be considered a blank/can/solvent measurement **kwargs This function takes two kinds of keyword arguments. If given a block name, it will move that block to the given position. If given a time duration, then that will be the duration of the run. Examples ======== >>> measure("H2O", frames=900) Perform a SANS measurment in the current position on a 1 mm thick water sample until the proton beam has released 900 proton pulses (approx 15 minutes). >>> measure("D2O", "LT", thickness=2.0, trans=True, Phi=3, uamps=10) Move to sample changer position LT, then adjust the CoarseZ motor to 38 mm. Finally, take a transmission measurement on a 2 mm thick deuterium sample for 10 µA hours of proton current. (approx 15 minutes). """ self._needs_setup() if not self.detector_lock() and not self.detector_on() and not trans: raise RuntimeError( "The detector is off. Either turn on the detector or " "use the detector_lock(True) to indicate that the detector " "is off intentionally") self.set_default_dae(dae, trans) self._setup_measurement(trans, blank) self.set_measurement_label(title) self.set_aperature(aperature) if pos: if isinstance(pos, str): if self.check_move_pos(pos=pos): info("Moving to sample changer position {}".format(pos)) gen.cset(SamplePos=pos) else: raise RuntimeError( "Position {} does not exist".format(pos)) elif callable(pos): info("Moving to position {}".format(pos.__name__)) pos() else: raise TypeError("Cannot understand position {}".format(pos)) for arg in kwargs: if arg in self.TIMINGS: continue info("Moving {} to {}".format(arg, kwargs[arg])) gen.cset(arg, kwargs[arg]) times = self.sanitised_timings(kwargs) gen.waitfor_move() gen.change_sample_par("Thick", thickness) info("Using the following Sample Parameters") self.printsamplepars() gen.change(title=title+self.title_footer) self._begin() info("Measuring {title:} for {time:} {units:}".format( title=title+self.title_footer, units=list(times.keys())[0], time=times[list(times.keys())[0]])) self._waitfor(**times) self._end()
[docs] def do_sans(self, title, pos=None, thickness=1.0, dae=None, blank=False, aperature="", **kwargs): """A wrapper around ``measure`` which ensures that the instrument is not in transmission mode Look at the documentation for ``measure`` to see the full set of parameters accepted. """ if "trans" in kwargs: del kwargs["trans"] self.measure(title, trans=False, pos=pos, thickness=thickness, dae=dae, blank=blank, aperature=aperature, **kwargs)
[docs] def do_trans(self, title, pos=None, thickness=1.0, dae=None, blank=False, aperature="", **kwargs): """A wrapper around ``measure`` which ensures that the instrument is not in transmission mode. Look at the documentation for ``measure`` to see the full set of parameters accepted. """ if "trans" in kwargs: del kwargs["trans"] self.measure(title, trans=True, pos=pos, thickness=thickness, dae=dae, blank=blank, aperature=aperature, **kwargs)
[docs] def measure_file(self, file_path, forever=False): """Perform a series of measurements based on a spreadsheet The file should contain comma separated values. Excel can easily produce files of this sort. The first line of the file is the header with each field giving the name of a parameter to the `measure` function. As always, the ``title`` parameter is mandatory. Each subsequent line of the file represents a single measurement with the fields indicating that values to pass to their corresponding keywords. If a cell is blank, the keyword's default parameter it used. Boolean values are represented by `True` and `False` and are not case sensitive. The script is run through the simulator to check for errors before attempting a real run. Parameters ---------- file_path : str The location of the script file forever : bool If set to True, the instrument will repeatedly run the script manually stopped. This can be useful for an overnight run where you want to keep measureing until the users return. """ from .Util import user_script @user_script def inner(): """Actually load and run the script""" import csv import ast with open(file_path, "rb") as csvfile: reader = csv.DictReader(csvfile) for row in reader: for k in row.keys(): if row[k].strip() == "": del row[k] elif row[k].upper() == "TRUE": row[k] = True elif row[k].upper() == "FALSE": row[k] = False else: try: row[k] = ast.literal_eval(row[k]) except ValueError: continue self.measure(**row) if forever: # pragma: no cover while True: inner() else: inner()
[docs] @staticmethod def convert_file(file_path): """Turn a CSV run list into a full python script This function allows the user to create simple scripts with Excel, then turn them into full Python scripts that can be edited and customised as needed. """ import csv import ast import os.path with open(file_path, "rb") as src, open(file_path+".py", "w") as out: out.write("from SansScripting import *\n") out.write("@user_script\n") out.write("def {}():\n".format( os.path.splitext( os.path.basename(file_path))[0].replace(" ", "_"))) reader = csv.DictReader(src) for row in reader: if "trans" in row and row["trans"] == "TRUE": header = "do_trans" else: header = "do_sans" title = row["title"] del row["title"] if "trans" in row: del row["trans"] out.write(' {}("{}", '.format(header, title)) if "pos" in row: out.write('"{}", '.format(row["pos"])) del row["pos"] for k in row.keys(): if row[k].strip() == "": del row[k] elif row[k].upper() == "TRUE": row[k] = True elif row[k].upper() == "FALSE": row[k] = False else: try: row[k] = ast.literal_eval(row[k]) except ValueError: row[k] = "\"" + row[k] + "\"" continue params = ", ".join([k + "=" + str(row[k]) for k in row]) out.write('{})\n'.format(params))
[docs] @staticmethod def printsamplepars(): """Display the basic sample parameters on the console.""" pars = gen.get_sample_pars() for par in ["Geometry", "Width", "Height", "Thick"]: info("{}={}".format(par, pars[par.upper()]))
[docs] def enumerate_dae(self): """List the supported DAE modes on this beamline.""" return [x[10:] for x in dir(self) if x.startswith("setup_dae_")]