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I noticed that some of the physical constants that one has access to on the HP Prime are ever so slightly off. Or to be more precise we in the meantime have more exact values for some of them and that isn't yet taken into account by the HP Prime (even with the most recent update).

Take for example the Stefan-Boltzmann constant sigma. It's value (without units) is
5.670 374 419*10^-8
according to what we currently know [1]. According to the HP Prime its value is however
5.670 367*10^-8

So I was wondering if I could somehow redefine these physical constants on my own HP Prime. If so, how? I'm aware of the possibility of adding user defined constants, but that's not what I'm looking for here.

Thinking more long-term I also wonder where and how I could report the underlying issue. Because then I would go through all the constants available on the HP Prime and compile a list of what should be updated and with what values.

[1] https://physics.nist.gov/cgi-bin/cuu/Value?sigma
There is a bug tracker. I see there is a ticket titled 'Update the Constants for Physics and Chemistry', which also refers to the page you mentioned, so there is a possibility that with the next firmware version, all the constant values listed on that website will be updated.

PK
If you want to change the unit values that are used inside the CAS, please do not use the bug tracker, reply below, and reply only with the lines that should be corrected, with the fixed value. Thanks!
Code:

  const mksa_unit __Angstrom_unit={1e-10,1,0,0,0,0,0,0,0};
  const mksa_unit __Btu_unit={1055.05585262,2,1,-2,0,0,0,0,0};
  const mksa_unit __Curie_unit={3.7e10,0,0,-1,0,0,0,0,0};
  const mksa_unit __FF_unit={.152449017237,0,0,0,0,0,0,0,1};
  const mksa_unit __Fdy_unit={96485.3365,0,0,1,1,0,0,0,0};
  const mksa_unit __Gal={0.01,1,0,-2,0,0,0,0,0};
  const mksa_unit __HFCC_unit={1400,1,0,0,0,0,0,0,0};
  const mksa_unit __L_unit={0.001,3,0,0,0,0,0,0,0};
  const mksa_unit __P_unit={.1,-1,1,-1,0,0,0,0,0};
  const mksa_unit __R_unit={0.000258,0,-1,1,1,0,0,0,0};
  const mksa_unit __Rankine_unit={5./9,0,0,0,0,1,0,0,0};
  const mksa_unit __St_unit={0.0001,2,0,-1,0,0,0,0,0};
  const mksa_unit __Wh_unit={3600,2,1,-2,0,0,0,0,0};
  const mksa_unit __a_unit={100,2,0,0,0,0,0,0,0};
  const mksa_unit __acre_unit={4046.87260987,2,0,0,0,0,0,0,0};
  const mksa_unit __arcmin_unit={2.90888208666e-4,0,0,0,0,0,0,0,0};
  const mksa_unit __arcs_unit={4.8481368111e-6,0,0,0,0,0,0,0,0};
  const mksa_unit __atm_unit={101325.0,-1,1,-2,0,0,0,0,0};
  const mksa_unit __au_unit={1.495979e11,1,0,0,0,0,0,0,0};
  const mksa_unit __b_unit={1e-28,2,0,0,0,0,0,0,0};
  const mksa_unit __bar_unit={1e5,-1,1,-2,0,0,0,0,0};
  const mksa_unit __bbl_unit={.158987294928,3,0,0,0,0,0,0,0};
  const mksa_unit __bblep_unit={.158987294928*0.857*41.76e9,2,1,-2,0,0,0,0,0};
  const mksa_unit __boe_unit={.158987294928*0.857*41.76e9,2,1,-2,0,0,0,0,0};
  const mksa_unit __bu={0.036368736,3,0,0,0,0,0,0,0};
  const mksa_unit __buUS={0.03523907,3,0,0,0,0,0,0,0};
  const mksa_unit __cal_unit={4.184,2,1,-2,0,0,0,0,0};
  const mksa_unit __cf_unit={1.08e6,2,1,-2,0,0,0,0,0};
  const mksa_unit __chain_unit={20.1168402337,1,0,0,0,0,0,0,0};
  const mksa_unit __ct_unit={0.0002,0,1,0,0,0,0,0,0};
  const mksa_unit __dB_unit={1,0,0,0,0,0,0,0,0};
  const mksa_unit __d_unit={86400,0,0,1,0,0,0,0,0};
  const mksa_unit __deg_unit={1.74532925199e-2,0,0,0,0,0,0,0,0};
  // const mksa_unit __degreeF_unit={5./9,0,0,0,0,1,0,0,0};
  const mksa_unit __dyn_unit={1e-5,1,1,-2,0,0,0,0,0};
  const mksa_unit __eV_unit={1.60217733e-19,2,1,-2,0,0,0,0,0};
  const mksa_unit __erg_unit={1e-7,2,1,-2,0,0,0,0,0};
  const mksa_unit __fath_unit={1.82880365761,1,0,0,0,0,0,0,0};
  const mksa_unit __fbm_unit={0.002359737216,3,0,0,0,0,0,0,0};
  const mksa_unit __fc_unit={10.7639104167,1,0,0,0,0,0,0,0};
  const mksa_unit __fermi_unit={1e-15,1,0,0,0,0,0,0,0};
  const mksa_unit __flam_unit={3.42625909964,-2,0,0,0,0,0,1,0};
  const mksa_unit __fm_unit={1.82880365761,1,0,0,0,0,0,0,0};
  const mksa_unit __ft_unit={0.3048,1,0,0,0,0,0,0,0};
  const mksa_unit __ftUS_unit={0.304800609601,1,0,0,0,0,0,0,0};
  const mksa_unit __g_unit={1e-3,0,1,0,0,0,0,0,0};
  const mksa_unit __galC_unit={0.00454609,3,0,0,0,0,0,0,0};
  const mksa_unit __galUK_unit={0.004546092,3,0,0,0,0,0,0,0};
  const mksa_unit __galUS_unit={0.003785411784,3,0,0,0,0,0,0,0};
  const mksa_unit __cu_unit={0.000236588236373,3,0,0,0,0,0,0,0};
  const mksa_unit __gf_unit={0.00980665,1,1,-2,0,0,0,0,0};
  const mksa_unit __gmol_unit={1,0,0,0,0,0,1,0,0};
  const mksa_unit __gon_unit={1.57079632679e-2,0,0,0,0,0,0,0};
  const mksa_unit __grad_unit={1.57079632679e-2,0,0,0,0,0,0,0,0};
  const mksa_unit __grain_unit={0.00006479891,0,1,0,0,0,0,0,0};
  const mksa_unit __h_unit={3600,0,0,1,0,0,0,0,0};
  const mksa_unit __ha_unit={10000,2,0,0,0,0,0,0,0};
  const mksa_unit __hp_unit={745.699871582,2,1,-3,0,0,0,0,0};
  const mksa_unit __in_unit={0.0254,1,0,0,0,0,0,0,0};
  const mksa_unit __inH2O_unit={249.08193551052,-1,1,-2,0,0,0,0,0};
  const mksa_unit __inHg_unit={3386.38815789,-1,1,-2,0,0,0,0,0};
  const mksa_unit __j_unit={86400,0,0,1,0,0,0,0,0};
  const mksa_unit __kip_unit={4448.22161526,1,1,-2,0,0,0,0,0};
  const mksa_unit __knot_unit={0.51444444444,1,0,-1,0,0,0,0,0};
  const mksa_unit __kph_unit={0.2777777777777,1,0,-1,0,0,0,0,0};
  const mksa_unit __l_unit={0.001,3,0,0,0,0,0,0,0};
  const mksa_unit __lam_unit={3183.09886184,-2,0,0,0,0,0,1,0};
  const mksa_unit __lb_unit={0.45359237,0,1,0,0,0,0,0,0};
  const mksa_unit __lbf_unit={4.44822161526,1,1,-2,0,0,0,0,0};
  //const mksa_unit __lbf_unit={4.44922161526,1,1,-2,0,0,0,0,0};
  const mksa_unit __lbmol_unit={453.59237,0,0,0,0,0,1,0,0};
  const mksa_unit __lbt_unit={0.3732417216,0,1,0,0,0,0,0,0};
  const mksa_unit __lep_unit={0.857*41.76e6,2,1,-2,0,0,0,0,0};
  const mksa_unit __liqpt_unit={0.000473176473,3,0,0,0,0,0,0,0};
  const mksa_unit __lyr_unit={9.46052840488e15,1,0,0,0,0,0,0,0};
  const mksa_unit __mi_unit={1609.344,1,0,0,0,0,0,0,0};
  const mksa_unit __miUS_unit={1609.34721869,1,0,0,0,0,0,0,0};
  const mksa_unit __mil_unit={0.0000254,1,0,0,0,0,0,0,0};
  const mksa_unit __mile_unit={1609.344,1,0,0,0,0,0,0,0};
  const mksa_unit __mille_unit={1852,1,0,0,0,0,0,0,0};
  const mksa_unit __mn_unit={60,0,0,1,0,0,0,0,0};
  const mksa_unit __mmHg_unit={133.322387415,-1,1,-2,0,0,0,0,0};
  const mksa_unit __molK_unit={1,0,0,0,0,1,1,0,0};
  const mksa_unit __mph_unit={0.44704,1,0,-1,0,0,0,0,0};
  const mksa_unit __nmi_unit={1852,1,0,0,0,0,0,0,0};
  const mksa_unit __oz_unit={0.028349523125,0,1,0,0,0,0,0,0};
  const mksa_unit __ozUK_unit={2.84130625e-5,3,0,0,0,0,0,0,0};
  const mksa_unit __ozfl_unit={2.95735295625e-5,3,0,0,0,0,0,0,0};
  const mksa_unit __ozt_unit={0.0311034768,0,1,0,0,0,0,0,0};
  const mksa_unit __pc_unit={3.08567758149137e16,1,0,0,0,0,0,0,0};
  const mksa_unit __pdl_unit={0.138254954376,1,1,-2,0,0,0,0,0};
  const mksa_unit __pk_unit={0.0088097675,3,0,0,0,0,0,0,0};
  const mksa_unit __psi_unit={6894.75729317,-1,1,-2,0,0,0,0,0};
  const mksa_unit __pt_unit={0.000473176473,3,0,0,0,0,0,0,0};
  const mksa_unit __ptUK_unit={0.0005682615,3,0,0,0,0,0,0,0};
  const mksa_unit __qt_unit={0.000946359246,3,0,0,0,0,0,0,0};
  const mksa_unit __rd_unit={0.01,2,0,-2,0,0,0,0,0};
  const mksa_unit __rem_unit={0.01,2,0,-2,0,0,0,0,0};
  const mksa_unit __rod_unit={5.02921005842,1,0,0,0,0,0,0,0};
  const mksa_unit __rpm_unit={0.0166666666667,0,0,-1,0,0,0,0,0};
  const mksa_unit __sb_unit={10000,-2,0,0,0,0,0,1,0};
  const mksa_unit __slug_unit={14.5939029372,0,1,0,0,0,0,0,0};
  const mksa_unit __st_unit={1,3,0,0,0,0,0,0,0};
  const mksa_unit __t_unit={1000,0,1,0,0,0,0,0,0};
  const mksa_unit __tbsp_unit={1.47867647813e-5,3,0,0,0,0,0,0,0};
  const mksa_unit __tec_unit={41.76e9/1.5,2,1,-2,0,0,0,0,0};
  const mksa_unit __tep_unit={41.76e9,2,1,-2,0,0,0,0,0};
  const mksa_unit __tepC_unit={830,1,0,0,0,0,0,0,0};
  const mksa_unit __tepcC_unit={1000,1,0,0,0,0,0,0,0};
  const mksa_unit __tepgC_unit={650,1,0,0,0,0,0,0,0};
  const mksa_unit __tex={1e-6,-1,1,0,0,0,0,0,0};
  const mksa_unit __therm_unit={105506000,2,1,-2,0,0,0,0,0};
  const mksa_unit __toe_unit={41.76e9,2,1,-2,0,0,0,0,0};
  const mksa_unit __ton_unit={907.18474,0,1,0,0,0,0,0,0};
  const mksa_unit __tonUK_unit={1016.0469088,0,1,0,0,0,0,0,0};
  const mksa_unit __Torr_unit={133.322368421,-1,1,-2,0,0,0,0,0};
  const mksa_unit __tr_unit={2*M_PI,0,0,0,0,0,0,0,0};
  const mksa_unit __tsp_unit={4.928921614571597e-6,3,0,0,0,0,0,0,0};
  const mksa_unit __u_unit={1.6605402e-27,0,1,0,0,0,0,0,0};
  const mksa_unit __yd_unit={0.9144,1,0,0,0,0,0,0,0};
  const mksa_unit __yr_unit={31556925.9747,0,0,1,0,0,0,0,0};
  const mksa_unit __micron_unit={1e-6,1,0,0,0,0,0,0,0};

  const mksa_unit __hbar_unit={1.05457266e-34,2,1,-1,0,0,0,0};        
  const mksa_unit __c_unit={299792458,1,0,-1,0,0,0,0};        
  const mksa_unit __g__unit={9.80665,1,0,-2,0,0,0,0};       
  const mksa_unit __IO_unit={1e-12,0,1,-3,0,0,0,0}; 
  const mksa_unit __epsilonox_unit={3.9,0,0,0,0,0,0,0}; 
  const mksa_unit __epsilonsi_unit={11.9,0,0,0,0,0,0,0,0}; 
  const mksa_unit __qepsilon0_unit={1.4185979e-30,-3,-1,5,3,0,0,0}; 
  const mksa_unit __epsilon0q_unit={55263469.6,-3,-1,3,1,0,0,0}; 
  const mksa_unit __kq_unit={8.617386e-5,2,1,-3,-1,-1,0,0}; 
  const mksa_unit __c3_unit={.002897756,1,0,0,0,1,0,0}; 
  const mksa_unit __lambdac_unit={ 0.00242631058e-9,1,0,0,0,0,0,0,0}; 
  const mksa_unit __f0_unit={2.4179883e14,0,0,-1,0,0,0,0}; 
  const mksa_unit __lambda0_unit={1239.8425e-9,1,0,0,0,0,0,0}; 
  const mksa_unit __muN_unit={5.0507866e-27,2,0,0,1,0,0,0}; 
  const mksa_unit __muB_unit={ 9.2740154e-24,2,0,0,1,0,0,0}; 
  const mksa_unit __a0_unit={.0529177249e-9,1,0,0,0,0,0,0}; 
  const mksa_unit __Rinfinity_unit={10973731.534,-1,0,0,0,0,0,0}; 
  const mksa_unit __Faraday_unit={96485.309,0,0,1,1,0,-1,0}; 
  const mksa_unit __phi_unit={2.06783461e-15,2,1,-2,-1,0,0,0};
  const mksa_unit __alpha_unit={7.29735308e-3,0,0,0,0,0,0,0}; 
  const mksa_unit __mpme_unit={1836.152701,0,0,0,0,0,0,0}; 
  const mksa_unit __mp_unit={1.6726231e-27,0,1,0,0,0,0,0}; 
  const mksa_unit __qme_unit={1.75881962e11,0,-1,1,1,0,0,0};
  const mksa_unit __me_unit={9.1093897e-31,0,1,0,0,0,0,0}; 
  const mksa_unit __qe_unit={1.60217733e-19,0,0,1,1,0,0,0};
  const mksa_unit __h__unit={6.6260755e-34,2,1,-1,0,0,0,0}; 
  const mksa_unit __G_unit={6.67408e-11,3,-1,-2,0,0,0,0}; 
  const mksa_unit __mu0_unit={1.25663706144e-6,1,1,-2,-2,0,0,0}; 
  const mksa_unit __epsilon0_unit={8.85418781761e-12,-3,-1,4,2,0,0,0}; 
  const mksa_unit __sigma_unit={ 5.67051e-8,0,1,-3,0,-4,0,0}; 
  const mksa_unit __StdP_unit={101325.0,-1,1,-2,0,0,0,0}; 
  const mksa_unit __StdT_unit={273.15,0,0,0,0,1,0,0}; 
  const mksa_unit __R__unit={8.31451,2,1,-2,0,-1,-1,0}; 
  const mksa_unit __Vm_unit={22.4141e-3,3,0,0,0,0,-1,0}; 
  const mksa_unit __k_unit={1.380658e-23,2,1,-2,0,-1,0,0}; 
  const mksa_unit __NA_unit={6.0221367e23,0,0,0,0,0,-1,0}; 
  const mksa_unit __mSun_unit={1.989e30,0,1,0,0,0,0,0}; 
  const mksa_unit __RSun_unit={6.955e8,1,0,0,0,0,0,0}; 
  const mksa_unit __PSun_unit={3.846e26,2,1,-3,0,0,0,0}; 
  const mksa_unit __mEarth_unit={5.9736e24,0,1,0,0,0,0,0}; 
  const mksa_unit __REarth_unit={6.371e6,1,0,0,0,0,0,0}; 
  const mksa_unit __sd_unit={8.61640905e4,0,0,1,0,0,0,0}; 
  const mksa_unit __syr_unit={3.15581498e7,0,0,1,0,0,0,0};
(10-02-2023 09:38 AM)parisse Wrote: [ -> ]If you want to change the unit values that are used inside the CAS, please do not use the bug tracker, reply below, and reply only with the lines that should be corrected, with the fixed value. Thanks!
Code:

  .
  .
  const mksa_unit __sigma_unit={ 5.67051e-8,0,1,-3,0,-4,0,0}; 
  .
  .

Why is this constant on the list different from the one in the HP Prime? Maybe I'm missing something...
[attachment=12608]
Furthermore, there's yet another value under the 'Help' key
[attachment=12609]
(10-02-2023 06:56 PM)komame Wrote: [ -> ]
(10-02-2023 09:38 AM)parisse Wrote: [ -> ]If you want to change the unit values that are used inside the CAS, please do not use the bug tracker, reply below, and reply only with the lines that should be corrected, with the fixed value. Thanks!
Code:

  .
  .
  const mksa_unit __sigma_unit={ 5.67051e-8,0,1,-3,0,-4,0,0}; 
  .
  .

Why is this constant on the list different from the one in the HP Prime? Maybe I'm missing something...
Because CAS and Home have their own unit computation systems. That's why I said "unit values that are used inside CAS".
(10-02-2023 09:38 AM)parisse Wrote: [ -> ]If you want to change the unit values that are used inside the CAS, please do not use the bug tracker, reply below, and reply only with the lines that should be corrected, with the fixed value. Thanks!

Mr. Parisse,
I have found several outdated constants. Below is a list of them with updated values.

Code:
  const mksa_unit __sigma_unit={5.670374419e-8,0,1,-3,0,-4,0,0}; // Stefan-Boltzmann constant
  const mksa_unit __h__unit={6.62607015e-34,2,1,-1,0,0,0,0}; // Planck constant
  const mksa_unit __hbar_unit={1.054571817e-34,2,1,-1,0,0,0,0}; // Reduced Planck constant
  const mksa_unit __eV_unit={1.602176634e-19,2,1,-2,0,0,0,0,0}; // Electron volt
  const mksa_unit __k_unit={1.380649e-23,2,1,-2,0,-1,0,0}; // Boltzmann constant
  const mksa_unit __NA_unit={6.02214076e23,0,0,0,0,0,-1,0}; // Avogadro constant
  const mksa_unit __G_unit={6.67430e-11,3,-1,-2,0,0,0,0}; // Newtonian constant of gravitation
  const mksa_unit __muB_unit={9.2740100783e-24,2,0,0,1,0,0,0}; // Bohr magneton
  const mksa_unit __muN_unit={5.0507837461e-27,2,0,0,1,0,0,0}; // Nuclear magneton
  const mksa_unit __me_unit={9.1093837015e-31,0,1,0,0,0,0,0}; // Electron mass
  const mksa_unit __mp_unit={1.67262192369e-27,0,1,0,0,0,0,0}; // Proton mass
  const mksa_unit __epsilon0_unit={8.8541878128e-12,-3,-1,4,2,0,0,0}; // Vacuum electric permittivity
  const mksa_unit __mu0_unit={1.25663706212e-6,1,1,-2,-2,0,0,0}; // Vacuum magnetic permeability

https://physics.nist.gov/cgi-bin/cuu/Value?sigma
https://physics.nist.gov/cgi-bin/cuu/Value?h
https://physics.nist.gov/cgi-bin/cuu/Value?hbar
https://physics.nist.gov/cgi-bin/cuu/Value?evj
https://physics.nist.gov/cgi-bin/cuu/Value?k
https://physics.nist.gov/cgi-bin/cuu/Value?na
https://physics.nist.gov/cgi-bin/cuu/Value?bg
https://physics.nist.gov/cgi-bin/cuu/Value?mub
https://physics.nist.gov/cgi-bin/cuu/Value?mun
https://physics.nist.gov/cgi-bin/cuu/Value?me
https://physics.nist.gov/cgi-bin/cuu/Value?mp
https://physics.nist.gov/cgi-bin/cuu/Value?ep0
https://physics.nist.gov/cgi-bin/cuu/Value?mu0

Best regards
Mr. Parisse,
besides the list of 13 constants above, I found an additional 5:

Code:
  const mksa_unit __R__unit={8.314462618,2,1,-2,0,-1,-1,0}; // molar gas constant
  const mksa_unit __Vm_unit={22.41396954e-3,3,0,0,0,0,-1,0}; // molar volume of ideal gas (273.15 K, 101.325 kPa)
  const mksa_unit __alpha_unit={7.2973525693e-3,0,0,0,0,0,0,0}; // fine-structure constant
  const mksa_unit __mpme_unit={1836.15267343,0,0,0,0,0,0,0}; // proton-electron mass ratio
  const mksa_unit __qme_unit={1.75882001076e11,0,-1,1,1,0,0,0}; // electron charge to mass quotient
There seems to be one more. According to https://physics.nist.gov/cgi-bin/cuu/Value?e,

Code:
const mksa_unit __qe_unit={1.60217733e-19,0,0,1,1,0,0,0};

should be

Code:
const mksa_unit __qe_unit={1.602176634e-19,0,0,1,1,0,0,0};

Since the conversion between Joule and eV depends on the fundamental charge, maybe it would be easier to set the value of __qe_unit to be __eV_unit or vice versa?
(10-05-2023 06:01 PM)nbc12 Wrote: [ -> ]There seems to be one more. According to https://physics.nist.gov/cgi-bin/cuu/Value?e,
Code:
const mksa_unit __qe_unit={1.60217733e-19,0,0,1,1,0,0,0};

should be

Code:
const mksa_unit __qe_unit={1.602176634e-19,0,0,1,1,0,0,0};

Indeed, I noticed that as well.
However, I didn't want to write another post without making sure that I wouldn't find anything else. Here are the rest that I managed to identify, and with this, I conclude my further search:

Code:
  const mksa_unit __lambdac_unit={2.42631023867e-12,1,0,0,0,0,0,0,0}; // Compton wavelength
  const mksa_unit __a0_unit={5.29177210903e-11,1,0,0,0,0,0,0}; // Bohr radius
  const mksa_unit __Rinfinity_unit={10973731.568160,-1,0,0,0,0,0,0}; // Rydberg constant  
  const mksa_unit __Faraday_unit={96485.33212,0,0,1,1,0,-1,0}; // Faraday constant
  const mksa_unit __phi_unit={2.067833848e-15,2,1,-2,-1,0,0,0}; // magnetic flux quantum
  const mksa_unit __qe_unit={1.602176634e-19,0,0,1,1,0,0,0}; // elementary charge
  const mksa_unit __mEarth_unit={5.9722e24,0,1,0,0,0,0,0}; // Earth mass

  const mksa_unit __lambda0_unit={1.239841984e-6,1,0,0,0,0,0,0}; // inverse meter-electron volt relationship

Please just check this last one (inverse meter-electron volt relationship), as I wasn't sure if it's just a coincidence:
https://physics.nist.gov/cgi-bin/cuu/Value?minvev

Mr. Parisse,
please update for this list as well. This is definitely the last one from my side.
Mr. Parisse,
could you confirm that this third part of the constants update has also been updated in the source code?

(10-05-2023 07:34 PM)komame Wrote: [ -> ]
Code:
  const mksa_unit __lambdac_unit={2.42631023867e-12,1,0,0,0,0,0,0,0}; // Compton wavelength
  const mksa_unit __a0_unit={5.29177210903e-11,1,0,0,0,0,0,0}; // Bohr radius
  const mksa_unit __Rinfinity_unit={10973731.568160,-1,0,0,0,0,0,0}; // Rydberg constant  
  const mksa_unit __Faraday_unit={96485.33212,0,0,1,1,0,-1,0}; // Faraday constant
  const mksa_unit __phi_unit={2.067833848e-15,2,1,-2,-1,0,0,0}; // magnetic flux quantum
  const mksa_unit __qe_unit={1.602176634e-19,0,0,1,1,0,0,0}; // elementary charge
  const mksa_unit __mEarth_unit={5.9722e24,0,1,0,0,0,0,0}; // Earth mass

  const mksa_unit __lambda0_unit={1.239841984e-6,1,0,0,0,0,0,0}; // inverse meter-electron volt relationship

I will be very grateful for a response.

Thank you.
Yes, I committed the change.
Hello friends,

I'm not able to get the corrected values into my machine. In which program core I have to embed the codeline "const mksa_unit __sigma..." to change the predefined values permamently?
You can't yourself, you have to wait for a firmware release on a Prime including these changes (the source code slice you see above is from Giac/Xcas).
(10-02-2023 05:28 AM)komame Wrote: [ -> ]There is a bug tracker. I see there is a ticket titled 'Update the Constants for Physics and Chemistry', which also refers to the page you mentioned, so there is a possibility that with the next firmware version, all the constant values listed on that website will be updated.

PK

I see, let's hope for the best then!

It's great that parisse already was able to update it in CAS though. (I understand that on the HP Prime we will only benefit from that after the next firmware update, but still.)

Thank you for compiling the list of physical constants that need(ed) to be updated, Piotr.
Hello Mr. Parisse,

thank you for your quick answer.
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