def _update_int_delay(instr, value, **kwargs):
"""
Function to validate value for int_delay before setting parameter
value and update instr attributes.
Args:
value to be validated and used for instrument attribute update
Checks:
0 <= value <= 0.1 seconds
number of samples discarded >= numtaps
Sets:
sample_rate attr of acq controller to be that of alazar
samples_per_record of acq controller
acquisition_kwarg['samples_per_record'] of acquisition param
"""
if (value is None) or not (0 <= value <= 0.1):
raise ValueError('int_delay must be 0 <= value <= 1')
alazar = instr._get_alazar()
instr.sample_rate = alazar.get_sample_rate()
samples_delay_min = (instr.filter_settings['numtaps'] - 1)
int_delay_min = samples_delay_min / instr.sample_rate
if value < int_delay_min:
logging.warning(
'delay is less than recommended for filter choice: '
'(expect delay >= {})'.format(int_delay_min))
# update acquision kwargs and acq controller value
total_time = value + (instr.int_time() or 0)
samples_needed = total_time * instr.sample_rate
instr.samples_per_record = helpers.roundup(samples_needed,
instr.samples_divisor)
instr.acquisition.acquisition_kwargs.update(
samples_per_record=instr.samples_per_record)
def _update_samples_per_record(self, sample_rate, int_time, int_delay):
"""
Keeps non settable samples_per_record up to date with int_time int_delay
and updates setpoints as needed.
"""
total_time = (int_time or 0) + (int_delay or 0)
samples_needed = total_time * sample_rate
samples_per_record = helpers.roundup(samples_needed,
self.samples_divisor)
self.samples_per_record._save_val(samples_per_record)
self.acquisition.set_setpoints_and_labels()
def _update_int_time(instr, value, **kwargs):
"""
Function to validate value for int_time before setting parameter
value and update instr attributes.
Args:
value to be validated and used for instrument attribute update
Checks:
0 <= value <= 0.1 seconds
number of oscilation measured in this time
oversampling rate
Sets:
sample_rate attr of acq controller to be that of alazar
samples_per_record of acq controller
acquisition_kwarg['samples_per_record'] of acquisition param
setpoints of acquisiton param
shape of acquisition param
"""
if (value is None) or not (0 <= value <= 0.1):
raise ValueError('int_time must be 0 <= value <= 1')
alazar = instr._get_alazar()
instr.sample_rate = alazar.get_sample_rate()
if instr.get_max_demod_freq() is not None:
min_oscilations_measured = value * instr.get_max_demod_freq()
oversampling = instr.sample_rate / (2 * instr.get_max_demod_freq())
if min_oscilations_measured < 10:
logging.warning('{} oscilations measured for largest '
'demod freq, recommend at least 10: '
'decrease sampling rate, take '
'more samples or increase demodulation '
'freq'.format(min_oscilations_measured))
elif oversampling < 1:
logging.warning('oversampling rate is {}, recommend > 1: '
'increase sampling rate or decrease '
'demodulation frequency'.format(oversampling))
if instr.int_delay() is None:
instr.int_delay.to_default()
# update acquisition parameter shapes
start = instr.int_delay()
stop = start + value
npts = int(value * instr.sample_rate)
instr.acquisition.update_sweep(start, stop, npts)
# update acquision kwargs and acq controller value
total_time = value + instr.int_delay()
samples_needed = total_time * instr.sample_rate
instr.samples_per_record = helpers.roundup(samples_needed,
instr.samples_divisor)
instr.acquisition.acquisition_kwargs.update(
samples_per_record=instr.samples_per_record)