[n,u]=my_const(c)

function [n,u]=my_const(c)
%CONSTANT  Get physical constant.
%   [N,U] = CONSTANT(C) retreives the constant C (string)
%   and returns its value to N. The optional output U is
%   the unit of the constant (in SI).
%
%   See also CONVERT.

% Copyright (c) 2001-12-08, B. Rasmus Anthin.
% Revision 2002-12-31, 2003-01-06, 2003-04-22.

switch c
 case {'Pe','P_e'}
   u='s';   
   n=86164.09890369732;
case {'T0','T_0'}
   n=273.15;
   u='K';
case {'c','c0'}
   n=299792458;
   u='m/s';
case {'mu0','u0'}
   n=4*pi*10^-7;
   u='Vs/Am';
case {'epsilon0','eps0','e0'}
   n=1/(299792458^2*4*pi*10^-7);
   u='As/Vm';
case 'G'
   n=6.67259e-11;
   u='Nm^2/kg^2';
case 'g'
   n=9.80665;
   u='m/s^2';
case {'me','m_e'}
   n=9.109390e-31;
   u='kg';
case {'mmu','m_mu'}
   n=1.883533e-28;
   u='kg';
case {'mp','m_p'}
   n=1.672623e-27;
   u='kg';
case {'mn','m_n'}
   n=1.674929e-27;
   u='kg';
case {'re','r_e'}
   n=2.817941e-15;
   u='m';
case 'a0'
   n=.52917725;
   u='';
case 'lambda_e'
   n=2.4263106e-12;
   u='m';
case 'lambda_p'
   n=1.3214100e-15;
   u='m';
case {'EH','E_H'}
   n=13.605698;
   u='eV';
case {'e','q','q0'}
   n=1.60217733e-19;
   u='C';
case {'muB','mu_B'}
   n=5.788383e-5;
   u='eV/T';
case {'muN','mu_N'}
   n=3.152452e-8;
   u='eV/T';
case 'mu_e'
   n=-9.284770e-24;
   u='J/T';
case 'mu_p'
   n=1.4106076e-26;
   u='J/T';
case 'mu_n'
   n=-1.9130427*3.152452e-8;
   u='J/T';
case 'mu_mu'
   n=4.490451e-26;
   u='J/T';
case 'h'
   n=6.6260755e-34;
   u='Js';
case {'h-','hbar','h/'}
   n=1.0545727e-34;
   u='Js';
case {'Rinf','R_inf'}
   n=1.09737315e7;
   u='1/m';
case 'alpha'
   n=7.297353e-3;
   u='';
case {'sigma','sigma_sb'}
   n=2*pi^5*constant('k')^4/(15*constant('h')^3*constant('c')^2);
   u='W/m^2/K^4';
case 'a'
   n=7.5659e-16;
   u='J/m^3/K^4';
case 'b_v'
   n=5.8786e10;
   u='1/s/K';
case 'b_lambda'
   n=2.8978e-3;
   u='mK';
case {'k','kB','k_B'}
   n=1.38066e-23;
   u='J/K';
case 'L'
   n=2.44304e-8;
   u='V^2/K^2';
case 'l_P1'
   n=1.616e-35;
   u='m';
case 'm_P1'
   n=2.177e-8;
   u='kg';
case 't_P1'
   n=5.391e-44;
   u='s';
case 'T_P1'
   n=1.417e32;
   u='K';
case {'NA','N_A'}
   n=6.022137e23;
   u='1/mol';
case 'V0'
   n=22.4141;
   u='dm^3/mol';
case 'R'
   n=8.31451;
   u='J/mol/K';
case 'F'
   n=9.648531e4;
   u='C/mol';
case {'Kj','K_j'}
   n=4.835977e14;
   u='Hz/V';
case {'Rk','R_k'}
   n=2.5812806e4;
   u='ohm';
case {'Me','ME','M_e','M_E'}
   n=5.98e24;
   u='kg';
case {'Ms','MS','M_s','M_S'}
   n=1.99e30;
   u='kg';
case {'Ree','REe','R_ee','R_Ee'}
   n=6.37816e6;
   u='m';
case {'Rep','REp','R_ep','R_Ep'}
   n=6.35678e6;
   u='m';
end