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1 change: 1 addition & 0 deletions CHANGELOG.md
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Expand Up @@ -799,6 +799,7 @@
#### [nidmm] Unreleased
- Added
- Added the `nidmm_measure_ac_volts.py` example.
- Added the `nidmm_improve_dc_noise_rejection.py` example.
- (Common) Added `nitlsconfig[grpc]>=1.0.0a2` to the optional gRPC dependencies.
- Changed
- Removed
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9 changes: 9 additions & 0 deletions docs/nidmm/examples.rst
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Expand Up @@ -12,6 +12,15 @@ nidmm_fetch_waveform.py
:encoding: utf8
:caption: `(nidmm_fetch_waveform.py) <https://github.com/ni/nimi-python/blob/master/src/nidmm/examples/nidmm_fetch_waveform.py>`_

nidmm_improve_dc_noise_rejection.py
-----------------------------------

.. literalinclude:: ../../src/nidmm/examples/nidmm_improve_dc_noise_rejection.py
:language: python
:linenos:
:encoding: utf8
:caption: `(nidmm_improve_dc_noise_rejection.py) <https://github.com/ni/nimi-python/blob/master/src/nidmm/examples/nidmm_improve_dc_noise_rejection.py>`_

nidmm_measure_ac_volts.py
-------------------------

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61 changes: 61 additions & 0 deletions src/nidmm/examples/nidmm_improve_dc_noise_rejection.py
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#!/usr/bin/python

import argparse
import nidmm
import sys


def example(resource_name, options, function, range, digits, aperture_time, dc_noise_rejection, sample_count, auto_zero, number_of_averages):
with nidmm.Session(resource_name=resource_name, options=options) as session:
session.configure_measurement_digits(measurement_function=nidmm.Function[function], range=range, resolution_digits=digits)
session.configure_multi_point(trigger_count=1, sample_count=sample_count)
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session.auto_zero = nidmm.AutoZero[auto_zero]
session.aperture_time_units = nidmm.ApertureTimeUnits.SECONDS
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# To reject noise at frequency f, choose the aperture time based on the weighting mode:
# NORMAL: a multiple of 1/f; SECOND_ORDER: a multiple of 2/f;
# HIGH_ORDER: at least 4/f, with no benefit to going above 4.5/f.
session.aperture_time = aperture_time
# NORMAL weighs all samples equally; SECOND_ORDER and HIGH_ORDER weigh samples in the middle of the aperture more.
session.dc_noise_rejection = nidmm.DCNoiseRejection[dc_noise_rejection]
# For aperture times over 100 ms, enable AutoZero to compensate for drift.
# The DMM takes shorter measurements, applies a new AutoZero offset to each,
# averages them, and returns one value.
Comment on lines +20 to +22

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We're setting auto_zero, way up above. Does this comment need to be split?
Or maybe we set auto_zero down here?

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Maybe I'm nitpicking, but I feel like this comment could also be clearer. The property that gets set is auto_zero. AutoZero is the enum and it's not like we have a feature with that spelling. The user manual page title it "Auto Zero".
https://www.ni.com/docs/en-US/bundle/ni-dmm/page/auto-zero.html

@marcoskirsch Do you have any thoughts on this?

session.number_of_averages = number_of_averages
measurements = session.read_multi_point(array_size=sample_count)
print(f'Measurements for {sample_count} Samples: {measurements}')


def _main(argsv):
supported_functions = list(nidmm.Function.__members__.keys())
supported_noise_rejection_modes = list(nidmm.DCNoiseRejection.__members__.keys())
parser = argparse.ArgumentParser(description='Performs a multipoint DC voltage measurement with configurable DC noise rejection.', formatter_class=argparse.ArgumentDefaultsHelpFormatter)
parser.add_argument('-n', '--resource-name', default='PXI1Slot2', help='Contains the resource_name of the device to initialize.')
parser.add_argument('-op', '--option-string', default='', type=str, help='Sets the initial value of certain attributes for the session.')
parser.add_argument('-f', '--function', default='DC_VOLTS', choices=supported_functions, type=str.upper, help='Specifies the measurement_function used to acquire the measurement.')
parser.add_argument('-r', '--range', default=0.1, type=float, help='Specifies the range for the function specified in the Measurement_Function parameter.')
parser.add_argument('-d', '--digits', default=6.5, type=float, help='Specifies the resolution of the measurement in digits.')
parser.add_argument('--auto-zero', default='OFF', choices=nidmm.AutoZero.__members__.keys(), type=str.upper, help='Specifies the AutoZero mode.')
parser.add_argument('-a', '--aperture-time', default=0.1, type=float, help='Specifies the measurement aperture time for the current configuration, in seconds.')
parser.add_argument('--dc-noise-rejection', default='NORMAL', choices=supported_noise_rejection_modes, type=str.upper, help='Specifies the DC noise rejection mode.')
parser.add_argument('-s', '--sample-count', default=10, type=int, help='Specifies the number of measurements the DMM takes each time it receives a trigger in a multiple point acquisition.')
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parser.add_argument('--number-of-averages', default=8, type=int, help='Specifies the number of averages to perform in a measurement.')
args = parser.parse_args(argsv)
example(args.resource_name, args.option_string, args.function, args.range, args.digits, args.aperture_time, args.dc_noise_rejection, args.sample_count, args.auto_zero, args.number_of_averages)


def main():
_main(sys.argv[1:])


def test_example():
options = {'simulate': True, 'driver_setup': {'Model': '4082', 'BoardType': 'PXIe', }, }
example('PXI1Slot2', options, 'DC_VOLTS', 0.1, 6.5, 0.1, 'NORMAL', 10, 'OFF', 8)


def test_main():
cmd_line = ['--option-string', 'Simulate=1, DriverSetup=Model:4082; BoardType:PXIe', ]
_main(cmd_line)


if __name__ == '__main__':
main()
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