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Updated definition of US survey units to reflect the 2022 revision by NIST/NGS #1920

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Updated definition of US survey units to reflect the 2022 revision by NIST/NGS #1920

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e89cdf0
Updated definition of US survey units to reflect the 2022 revision by…
jacob-indigo Jan 11, 2024
c849a7d
Fix whitespace
jacob-indigo Jan 11, 2024
e56fead
Updated sources
jacob-indigo Jan 12, 2024
a1a70ae
Fix CHANGES
jacob-indigo May 8, 2025
c13b616
Address review feedback
jacob-indigo May 8, 2025
c127151
Move standard units to USCSLengthInternational and keep historical un…
jacob-indigo May 8, 2025
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Expand Up @@ -19,6 +19,7 @@ Pint Changelog
- Add membrane filtration flux and permeability dimensionality, and shorthand "LMH". (#2116)
- Fix find_shortest_path to use breadth first search (#2146)
- Fix typo in ``pyproject.toml``: rename ``AS_MIP`` to ``HAS_MIP`` so that MIP support is correctly detected. (#2152)
- Update definition of US survey units to reflect the 2022 revision by NIST/NGS. (#1920)


0.24.4 (2024-11-07)
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50 changes: 36 additions & 14 deletions pint/default_en.txt
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Expand Up @@ -536,6 +536,9 @@ neper = 1 ; logbase: 2.71828182845904523536028747135266249775724709369995; logfa
# Mostly for length, area, volume, mass, force
# (customary or specialized units)

# Note: historically, many of the units in this group were derived from each other (e.g. 1 chain = 10 fathoms = 4 rods = 100 links)
# but we've followed the NIST's lead here and defined all of the units directly based on "common" units (feet and miles)
# Source: Warfield, L. , Konijnenburg, J. , Lippa, K. , Lee, G. , Minnich, L. and Williams, J. (2023), Specifications, Tolerances, and Other Technical Requirements for Weighing and Measuring Devices as adopted by the 108th National Conference on Weights and Measures, Handbook (NIST HB), National Institute of Standards and Technology, Gaithersburg, MD, [online], https://doi.org/10.6028/NIST.HB.44-2024 (Accessed January 12, 2024)
@group USCSLengthInternational
thou = 1e-3 * inch = th = mil_length
inch = yard / 36 = in = international_inch = inches = international_inches
Expand All @@ -553,25 +556,44 @@ neper = 1 ; logbase: 2.71828182845904523536028747135266249775724709369995; logfa
cubic_inch = in ** 3 = cu_in
cubic_foot = ft ** 3 = cu_ft = cubic_feet
cubic_yard = yd ** 3 = cu_yd

link = 0.66 * foot = li = survey_link
fathom = 6 * foot
rod = 16.5 * foot = rd = pole = perch
chain = 66 * foot = ch
furlong = 660 * foot = fur
cables_length = 720 * foot
league = 3 * mile

square_rod = rod ** 2 = sq_rd = sq_rod = sq_pole = sq_perch
acre = 43560 * square_foot
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You could leave it as is was to minimize diffs. acre = 10 * chain ** 2

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I did this to be consistent with this statement across all of the units here

but we've followed the NIST's lead here and defined all of the units directly based on "common" units (feet and miles)

square_league = league ** 2

acre_foot = acre * foot = _ = acre_feet
@end

# The adoption of the international foot in 1959 temporarily permitted the continued use of the 1893 definition of the foot for survey purposes.
# That established the Survey Foot. After 2022, that exception was no longer permitted and all feet are feet (survey or otherwise).
# The units below are preserved here for historical applications.
# Source: Barton, J. , Blackwell, B. , Butcher, T. , Harshman, R., Lee, G. , Olson, D. (2019), Specifications, Tolerances, and Other Technical Requirements for Weighing and Measuring Devices as adopted by the 108th National Conference on Weights and Measures 2019, Handbook (NIST HB), National Institute of Standards and Technology, Gaithersburg, MD, [online], https://doi.org/10.6028/NIST.HB.44-2020 (Accessed January 12, 2024)
@group USCSLengthSurvey
link = 1e-2 * chain = li = survey_link
survey_foot = 1200 / 3937 * meter = sft
fathom = 6 * survey_foot
rod = 16.5 * survey_foot = rd = pole = perch
chain = 4 * rod
furlong = 40 * rod = fur
cables_length = 120 * fathom
survey_mile = 5280 * survey_foot = smi = us_statute_mile
league = 3 * survey_mile

square_rod = rod ** 2 = sq_rod = sq_pole = sq_perch
acre = 10 * chain ** 2
square_survey_mile = survey_mile ** 2 = _ = section
square_league = league ** 2

acre_foot = acre * survey_foot = _ = acre_feet
square_survey_mile = survey_mile ** 2

survey_link = 0.66 * survey_foot = sli
survey_fathom = 6 * survey_foot
survey_rod = 16.5 * survey_foot = srd = survey_pole = survey_perch
survey_chain = 66 * survey_foot = sch
survey_furlong = 660 * survey_foot = sfur
survey_cables_length = 720 * survey_foot
survey_league = 3 * survey_mile

square_survey_rod = survey_rod ** 2 = sq_srd = sq_survey_rod = sq_survey_pole = sq_survey_perch
survey_acre = 10 * survey_chain ** 2
square_survey_league = survey_league ** 2

survey_acre_foot = survey_acre * survey_foot = _ = survey_acre_feet
@end

@group USCSDryVolume
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