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quanta.map - Function

1.5.1 list known unit names and constants


Description

map lists the known mapping of units and constants. It has a single argument, which can be a coded string (no-case, minimax match):

all
all of the following units (not constants): also the default
Prefix
known decimal prefixes
SI
known SI units
Customary
a set of customary units known to programs
User
units defined by the user
Constants
known constants (note: only ’const’, ’Const’, ’constants’ and ’Constants’ recognised).

Arguments





Inputs

v

type of information to list - coded string

allowed:

string

Default:

all

Returns
string

Example

 
 
"""  
#  
print "\t----\t map Ex 1 \t----"  
print qa.map(’pre’) # list decimal prefixes  
#        == Prefix ==== 20 ====  
#        E         (exa)                        1e+18  
#        G         (giga)                       1000000000  
#        M         (mega)                       1000000  
#        P         (peta)                       1e+15  
#        T         (tera)                       1e+12  
#        Y         (yotta)                      1e+24  
#        Z         (zetta)                      1e+21  
#        a         (atto)                       1e-18  
#        c         (centi)                      0.01  
#        d         (deci)                       0.1  
#        da        (deka)                       10  
#        f         (femto)                      1e-15  
#        h         (hecto)                      100  
#        k         (kilo)                       1000  
#        m         (milli)                      0.001  
#        n         (nano)                       1e-09  
#        p         (pico)                       1e-12  
#        u         (micro)                      1e-06  
#        y         (yocto)                      1e-24  
#        z         (zepto)                      1e-21  
print qa.map(’Constants’) # list known constants  
#        == Constants ====  
#        pi    3.14..                    3.14159  
#        ee    2.71..                    2.71828  
#        c     light vel.                2.99792e+08 m/s  
#        G     grav. const               6.67259e-11 N.m2/kg2  
#        h     Planck const              6.62608e-34 J.s  
#        HI    HI line                   1420.41 MHz  
#        R     gas const                 8.31451 J/K/mol  
#        NA    Avogadro #                6.02214e+23 mol-1  
#        e     electron charge           1.60218e-19 C  
#        mp    proton mass               1.67262e-27 kg  
#        mp_me mp/me                     1836.15  
#        mu0   permeability vac.         1.25664e-06 H/m  
#        eps0  permittivity vac.         1.60218e-19 C  
#        k     Boltzmann const           1.38066e-23 J/K  
#        F     Faraday const             96485.3 C/mol  
#        me    electron mass             9.10939e-31 kg  
#        re    electron radius           2.8179e-15 m  
#        a0    Bohr’s radius             5.2918e-11 m  
#        R0    solar radius              6.9599e+08 m  
#        k2    IAU grav. const^2         0.000295912 AU3/d2/S0  
#  
"""  
 

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