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WP-34S galUS-> l Precision
12-15-2016, 04:49 PM
Post: #26
RE: WP-34S galUS-> l Precision
(12-11-2016 01:24 PM)Nigel (UK) Wrote:  I couldn't resist having a go myself! Below is my modified list of conversion factors; I've tried to be clear from where each has come. I've left the original ones in, commented out, so that the two can be compared.

So far as I know, all of these are either exact or correct to 16sf.

Code:

struct _constsml conversions[] = {
//    CONV("kg",    "lb",        "KG_LBM",    "0.4535924"),        // source: NIST
    CONV("kg",    "lb",        "KG_LBM",    "0.45359237"),        // source: NIST; exact
    
//    CONV("kg",    "stone",    "KG_STONE",    "6.3502936"),        // derived: 14 lbs to a stone
    CONV("kg",    "stone",    "KG_STONE",    "6.35029318"),        // derived: 14 lbs to a stone using exact lb; exact

//    CONV("kg",    "cwt",        "KG_CWT",    "50.8023488"),        // derived: 112lb to a long cwt
    CONV("kg",    "cwt",        "KG_CWT",    "50.80234544"),        // derived: 112lb to a long cwt using exact lb;exact

//    CONV("kg",    "s.cwt",    "KG_SHCWT",    "45.35924"),        // source: NIST hundredweight, short 100lb
    CONV("kg",    "s.cwt",    "KG_SHCWT",    "45.359237"),        // source: NIST hundredweight, short 100lb using exact lb; exact

//    CONV("g",    "oz",        "G_OZ",        "28.34952"),        // source: NIST
    CONV("g",    "oz",        "G_OZ",        "28.349523125"),        // source: NIST; 16oz to 1 lb using exact lb

//    CONV("g",    "tr.oz",    "G_TOZ",    "31.10348"),        // source: NIST
    CONV("g",    "tr.oz",    "G_TOZ",    "31.1034768"),        // source: NIST; 1 tr.oz = 480 grains; 1 lb = 7000 grains exactly; exact

    CONV("l",    "galUK",    "L_GALUK",    "4.54609"),        // source: NIST; also UK Weights and Measures act 1985; exact

//    CONV("l",    "galUS",    "L_GALUS",    "3.785412"),        // source: NIST
    CONV("l",    "galUS",    "L_GALUS",    "3.785411784"),        // source: NIST handbook 44 2017 appendix C; exact

//    CONV("l",    "cft",        "L_CUBFT",    "28.31685"),        // source: NIST
    CONV("l",    "cft",        "L_CUBFT",    "28.316846592"),        // source: 1 inch = 0.0254 m; exact

//    CONV("ml",    "flozUK",    "ML_FLOZUK",    "28.41306"),        // source: NIST oz UK fluid
    CONV("ml",    "flozUK",    "ML_FLOZUK",    "28.4130625"),        // source: 1 ukgallon = 8 pints; 1 pint = 20 flozuk; see above for exact ukgallon; exact

//    CONV("ml",    "flozUS",    "ML_FLOZUS",    "29.57353"),        // source: NIST oz US fluid
    CONV("ml",    "flozUS",    "ML_FLOZUS",    "29.5735295625"),        // source: NIST handbook 44 2017 appendix C; 1 floz = 1.8046875 in^3; exact

    CONV("cm",    "inches",    "CM_INCH",    "2.54"),        // source: NIST; exact already

    CONV("m",    "fathom",    "M_FATHOM",    "1.8288"),        // derived: 6 feet; exact

    CONV("m",    "feet",        "M_FEET",    "0.3048"),        // source: NIST; exact

//    CONV("m",    "feetUS",    "M_FEETUS",    "0.3048006096"),        // source: Wikipedia etc;
    CONV("m",    "feetUS",    "M_FEETUS",    "0.3048006096012192"),        // source: Wikipedia etc; usfoot = survey foot = 1200/3937 m exactly; number given is correct to 16sf

    CONV("m",    "yards",    "M_YARD",    "0.9144"),        // source: NIST; exact

    CONV("km",    "miles",    "KM_MILE",    "1.609344"),        // source: NIST; exact

    CONV("km",    "l.y.",        "KM_LY",    "9.4607304725808E12"),        // source: IAU (see http://www.hpmuseum.org/forum/thread-2262.html); exact

//    CONV("km",    "pc",        "KM_PC",    "3.085678E13"),        // source: NIST
    CONV("km",    "pc",        "KM_PC",    "3.085677581491367E13"),        // source: August 2015 IAU Resolution B2 defines parsec as 648000/pi AU; uses AU below; correct to 16sf

//    CONV("km",    "AU",        "KM_AU",    "149597900"),        // source: NIST, IAU 2009 gives 1.49597870700E11
    CONV("km",    "AU",        "KM_AU",    "149597870.7"),        // source: NIST, IAU 2009 gives 1.49597870700E11; value changed to this exact definition

    CONV("km",    "nmi",        "KM_NMI",    "1.852"),        // source: NIST; exact

//    CONV("m\232",    "square",    "M_SQUARE",    "9.290304"),        // derived: 
//    CONV("m\232",    "perch",    "M_PERCH",    "25.29285264"),        // derived: 

    CONV("ha",    "acres",    "HA_ACREUK",    "0.40468564224"),    // derived: 43560 square feet; exact

//    CONV("ha",    "acreUS",    "HA_ACREUS",    "0.4046873"),        // source: NIST
    CONV("ha",    "acreUS",    "HA_ACREUS",    "0.4046872609874252"),        // source: NIST; using exact definition of survey foot correct to 16sf

//    CONV("N",    "lbf",        "N_LBF",    "4.448222"),        // source: NIST
    CONV("N",    "lbf",        "N_LBF",    "4.4482216152605"),        // source: using g (standard) = 9.80665 N/kg from NIST constants and exact value for mass of 1lb; exact

//    CONV("J",    "Btu",        "J_BTU",    "1055.056"),        // source: NIST BTUit
    CONV("J",    "Btu",        "J_BTU",    "1055.05585262"),        // source: NIST; 1BTU = heat needed to raise temp of 1 lb water by 1 degF; using exact pound and calorie values gives result above

    CONV("J",    "cal",        "J_CAL",    "4.1868"),        // source: NIST calorie it (International Steam Table calorie); exact

    CONV("J",    "kWh",        "J_kWh",    "3600000"),        // source: NIST; exact

    CONV("Pa",    "atm",        "Pa_ATM",    "101325"),        // source: NIST atmosphere standard; exact

    CONV("Pa",    "bar",        "Pa_bar",    "100000"),        // source: NIST; exact

//    CONV("Pa",    "mmHg",        "Pa_mmHg",    "133.3224"),        // source: NIST cm mercury conventional
    CONV("Pa",    "mmHg",        "Pa_mmHg",    "133.322387415"),        // source: Wikipedia refers to BS 350: Part 1: 1974 - Conversion factors and tables. British Standards Institution. 1974. p. 49; exact

//    CONV("Pa",    "psi",        "Pa_psi",    "6894.757"),        // source: NIST pound-force per square inch
    CONV("Pa",    "psi",        "Pa_psi",    "6894.757293168361"),        // source: NIST pound-force per square inch; uses value for lbF above; correct to 16sf

//    CONV("Pa",    "inHg",        "Pa_inhg",    "3386.389"),        // source: NIST inch of mercury conventional
    CONV("Pa",    "inHg",        "Pa_inhg",    "3386.388640341"),        // source: NIST inch of mercury conventional; see mmHg above; exact

//    CONV("Pa",    "torr",        "Pa_torr",    "133.3224"),        // source: NIST
    CONV("Pa",    "torr",        "Pa_torr",    "133.3223684210526"),        // source: NIST; 101325/760 is exact value; corect to 16sf

//    CONV("W",    "hp(I)",    "W_HP550",    "745.6999"),        // source: NIST horsepower 550 ft . lb / s
    CONV("W",    "hp(I)",    "W_HP550",    "745.6998715822702"),        // source: NIST horsepower 550 ft . lb / s; using standard g; correct to 16sf

//    CONV("W",    "hp(M)",    "W_HP",        "735.4988"),        // source: NIST horsepower metric
    CONV("W",    "hp(M)",    "W_HP",        "735.49875"),        // source: NIST horsepower metric (lifting 75kg 1m in 1s) using standard g; exact

    CONV("W",    "hp(E)",    "W_HPe",    "746"),            // source: NIST horsepower electric; exact

//    CONV("t",    "tons",        "T_TON",    "1.016047"),        // source: NIST ton, long 2240lb
    CONV("t",    "tons",        "T_TON",    "1.0160469088"),        // source: NIST ton, long 2240lb; using exact lb; exact

//    CONV("t",    "s.tons",    "T_SHTON",    "0.9071847"),        // source: NIST ton, short 2000lb
    CONV("t",    "s.tons",    "T_SHTON",    "0.90718474"),        // source: NIST ton, short 2000lb; using exact lb; exact

    CONV(NULL, NULL, NULL, NULL)
};

Nigel (UK)

Thanks for posting this very useful info. I am glad to see the increased precision available for the WP-34S.

Interestingly, your high-precision results seem to be mostly identical to the built-in conversion factors in the HP-4X series except, of course, for the 16 digit precision. However, I have found a few discrepancies between your high-precision results and those given by the HP-50g. I am not sure on which side(s) the errors lie, but I wanted to bring the discrepancies to your attention.

The following are the HP-50's definitions which are different from the ones you listed:

Code:

1 galUK = 4.546092 l
1 flozUK = 28.413075 g (based on galUK above)
1 pc = 3.08567818585E13 km
1 l. y. = 9.46052840488E12 km
1 mm Hg = 133.322368421 Pa

This is not necessarily an exhaustive list, just the ones I noticed while poking around.

John
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Messages In This Thread
WP-34S galUS-> l Precision - Nick - 09-07-2016, 10:20 PM
RE: WP-34S galUS-> l Precision - Paul Dale - 09-07-2016, 11:56 PM
RE: WP-34S galUS-> l Precision - Joe Horn - 09-08-2016, 05:02 AM
RE: WP-34S galUS-> l Precision - Nick - 09-09-2016, 04:47 AM
RE: WP-34S galUS-> l Precision - Dol - 09-09-2016, 08:04 AM
RE: WP-34S galUS-> l Precision - Paul Dale - 09-09-2016, 08:05 AM
RE: WP-34S galUS-> l Precision - renif - 09-08-2016, 01:15 PM
RE: WP-34S galUS-> l Precision - Nick - 09-08-2016, 02:49 PM
RE: WP-34S galUS-> l Precision - Nick - 09-10-2016, 05:22 PM
RE: WP-34S galUS-> l Precision - Nick - 09-11-2016, 04:11 PM
RE: WP-34S galUS-> l Precision - Dieter - 11-27-2016, 03:12 PM
RE: WP-34S galUS-> l Precision - Paul Dale - 12-10-2016, 11:19 PM
RE: WP-34S galUS-> l Precision - John Keith - 12-15-2016 04:49 PM
RE: WP-34S galUS-> l Precision - Paul Dale - 12-12-2016, 01:46 AM
RE: WP-34S galUS-> l Precision - Paul Dale - 12-12-2016, 09:02 AM
RE: WP-34S galUS-> l Precision - emece67 - 12-14-2016, 03:41 PM
RE: WP-34S galUS-> l Precision - Vtile - 12-16-2016, 02:46 PM
RE: WP-34S galUS-> l Precision - Vtile - 12-16-2016, 10:50 PM



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