Units
=====

A quantity  always has a unit:

.. code:: python

    >>> a = PhysicalQuantity(1, 'm')
    >>> a.unit
    <PhysicalUnit m>

The convenience class 'q' can be used to specify units:
-------------------------------------------------------

.. code:: python

    >>> %precision 2
    >>> from PhysicalQuantities import q
    >>> q.mm, q.m, q.km
    (1 mm, 1 m, 1 km)
    >>> 2 * q.mm**2

:math:`2 \text{mm}^{2}`

.. code:: python

    >>> v = 30 * q.m / q.s
    >>> v.to('km/h')

:math:`108.00 \frac{\text{km}}{\text{h}}`


.. code:: python

    >>> p = 20*q.dBm + 3*q.dB
    >>> p, p.W
    (23 dBm, 0.20 W)


List of defined units
---------------------

.. code:: python

    >>> q.table
    {'A': <PhysicalUnit A>,
     'C': <PhysicalUnit C>,
     'F': <PhysicalUnit F>,
     'GA': <PhysicalUnit GA>,
     'GC': <PhysicalUnit GC>,
     'GF': <PhysicalUnit GF>,
     'GH': <PhysicalUnit GH>,
     'GHz': <PhysicalUnit GHz>,
     'GJ': <PhysicalUnit GJ>,
     'GK': <PhysicalUnit GK>,
     'GN': <PhysicalUnit GN>,
     'GOhm': <PhysicalUnit GOhm>,
     'GPa': <PhysicalUnit GPa>,
     'GS': <PhysicalUnit GS>,
     'GT': <PhysicalUnit GT>,
     'GV': <PhysicalUnit GV>,
     'GW': <PhysicalUnit GW>,
     'GWb': <PhysicalUnit GWb>,
     'Gcd': <PhysicalUnit Gcd>,
     'Gg': <PhysicalUnit Gg>,
     'Glm': <PhysicalUnit Glm>,
     'Glx': <PhysicalUnit Glx>,
     'Gm': <PhysicalUnit Gm>,
     'Gmol': <PhysicalUnit Gmol>,
     'Grad': <PhysicalUnit Grad>,
     'Gs': <PhysicalUnit Gs>,
     'Gsr': <PhysicalUnit Gsr>,
     'H': <PhysicalUnit H>,
     'Hz': <PhysicalUnit Hz>,
     'J': <PhysicalUnit J>,
     'K': <PhysicalUnit K>,
     'MA': <PhysicalUnit MA>,
     'MC': <PhysicalUnit MC>,
     'MF': <PhysicalUnit MF>,
     'MH': <PhysicalUnit MH>,
     'MHz': <PhysicalUnit MHz>,
     'MJ': <PhysicalUnit MJ>,
     'MK': <PhysicalUnit MK>,
     'MN': <PhysicalUnit MN>,
     'MOhm': <PhysicalUnit MOhm>,
     'MPa': <PhysicalUnit MPa>,
     'MS': <PhysicalUnit MS>,
     'MT': <PhysicalUnit MT>,
     'MV': <PhysicalUnit MV>,
     'MW': <PhysicalUnit MW>,
     'MWb': <PhysicalUnit MWb>,
     'Mcd': <PhysicalUnit Mcd>,
     'Mg': <PhysicalUnit Mg>,
     'Mlm': <PhysicalUnit Mlm>,
     'Mlx': <PhysicalUnit Mlx>,
     'Mm': <PhysicalUnit Mm>,
     'Mmol': <PhysicalUnit Mmol>,
     'Mrad': <PhysicalUnit Mrad>,
     'Ms': <PhysicalUnit Ms>,
     'Msr': <PhysicalUnit Msr>,
     'N': <PhysicalUnit N>,
     'Ohm': <PhysicalUnit Ohm>,
     'Pa': <PhysicalUnit Pa>,
     'S': <PhysicalUnit S>,
     'T': <PhysicalUnit T>,
     'TA': <PhysicalUnit TA>,
     'TC': <PhysicalUnit TC>,
     'TF': <PhysicalUnit TF>,
     'TH': <PhysicalUnit TH>,
     'THz': <PhysicalUnit THz>,
     'TJ': <PhysicalUnit TJ>,
     'TK': <PhysicalUnit TK>,
     'TN': <PhysicalUnit TN>,
     'TOhm': <PhysicalUnit TOhm>,
     'TPa': <PhysicalUnit TPa>,
     'TS': <PhysicalUnit TS>,
     'TT': <PhysicalUnit TT>,
     'TV': <PhysicalUnit TV>,
     'TW': <PhysicalUnit TW>,
     'TWb': <PhysicalUnit TWb>,
     'Tcd': <PhysicalUnit Tcd>,
     'Tg': <PhysicalUnit Tg>,
     'Tlm': <PhysicalUnit Tlm>,
     'Tlx': <PhysicalUnit Tlx>,
     'Tm': <PhysicalUnit Tm>,
     'Tmol': <PhysicalUnit Tmol>,
     'Trad': <PhysicalUnit Trad>,
     'Ts': <PhysicalUnit Ts>,
     'Tsr': <PhysicalUnit Tsr>,
     'V': <PhysicalUnit V>,
     'W': <PhysicalUnit W>,
     'Wb': <PhysicalUnit Wb>,
     'aA': <PhysicalUnit aA>,
     'aC': <PhysicalUnit aC>,
     'aF': <PhysicalUnit aF>,
     'aH': <PhysicalUnit aH>,
     'aHz': <PhysicalUnit aHz>,
     'aJ': <PhysicalUnit aJ>,
     'aK': <PhysicalUnit aK>,
     'aN': <PhysicalUnit aN>,
     'aOhm': <PhysicalUnit aOhm>,
     'aPa': <PhysicalUnit aPa>,
     'aS': <PhysicalUnit aS>,
     'aT': <PhysicalUnit aT>,
     'aV': <PhysicalUnit aV>,
     'aW': <PhysicalUnit aW>,
     'aWb': <PhysicalUnit aWb>,
     'acd': <PhysicalUnit acd>,
     'ag': <PhysicalUnit ag>,
     'alm': <PhysicalUnit alm>,
     'alx': <PhysicalUnit alx>,
     'am': <PhysicalUnit am>,
     'amol': <PhysicalUnit amol>,
     'arad': <PhysicalUnit arad>,
     'arcmin': <PhysicalUnit arcmin>,
     'arcsec': <PhysicalUnit arcsec>,
     'as': <PhysicalUnit as>,
     'asr': <PhysicalUnit asr>,
     'cA': <PhysicalUnit cA>,
     'cC': <PhysicalUnit cC>,
     'cF': <PhysicalUnit cF>,
     'cH': <PhysicalUnit cH>,
     'cHz': <PhysicalUnit cHz>,
     'cJ': <PhysicalUnit cJ>,
     'cK': <PhysicalUnit cK>,
     'cN': <PhysicalUnit cN>,
     'cOhm': <PhysicalUnit cOhm>,
     'cPa': <PhysicalUnit cPa>,
     'cS': <PhysicalUnit cS>,
     'cT': <PhysicalUnit cT>,
     'cV': <PhysicalUnit cV>,
     'cW': <PhysicalUnit cW>,
     'cWb': <PhysicalUnit cWb>,
     'ccd': <PhysicalUnit ccd>,
     'cd': <PhysicalUnit cd>,
     'cg': <PhysicalUnit cg>,
     'clm': <PhysicalUnit clm>,
     'clx': <PhysicalUnit clx>,
     'cm': <PhysicalUnit cm>,
     'cmol': <PhysicalUnit cmol>,
     'crad': <PhysicalUnit crad>,
     'cs': <PhysicalUnit cs>,
     'csr': <PhysicalUnit csr>,
     'dB': 1 dB,
     'dBA': 1 dBA,
     'dBV': 1 dBV,
     'dBW': 1 dBW,
     'dBd': 1 dBd,
     'dBi': 1 dBi,
     'dBm': 1 dBm,
     'dBmA': 1 dBmA,
     'dBmV': 1 dBmV,
     'dBnA': 1 dBnA,
     'dBnV': 1 dBnV,
     'dBsm': 1 dBsm,
     'dBuA': 1 dBuA,
     'dBuV': 1 dBuV,
     'deg': <PhysicalUnit deg>,
     'fA': <PhysicalUnit fA>,
     'fC': <PhysicalUnit fC>,
     'fF': <PhysicalUnit fF>,
     'fH': <PhysicalUnit fH>,
     'fHz': <PhysicalUnit fHz>,
     'fJ': <PhysicalUnit fJ>,
     'fK': <PhysicalUnit fK>,
     'fN': <PhysicalUnit fN>,
     'fOhm': <PhysicalUnit fOhm>,
     'fPa': <PhysicalUnit fPa>,
     'fS': <PhysicalUnit fS>,
     'fT': <PhysicalUnit fT>,
     'fV': <PhysicalUnit fV>,
     'fW': <PhysicalUnit fW>,
     'fWb': <PhysicalUnit fWb>,
     'fcd': <PhysicalUnit fcd>,
     'fg': <PhysicalUnit fg>,
     'flm': <PhysicalUnit flm>,
     'flx': <PhysicalUnit flx>,
     'fm': <PhysicalUnit fm>,
     'fmol': <PhysicalUnit fmol>,
     'frad': <PhysicalUnit frad>,
     'fs': <PhysicalUnit fs>,
     'fsr': <PhysicalUnit fsr>,
     'g': <PhysicalUnit g>,
     'h': <PhysicalUnit h>,
     'kA': <PhysicalUnit kA>,
     'kC': <PhysicalUnit kC>,
     'kF': <PhysicalUnit kF>,
     'kH': <PhysicalUnit kH>,
     'kHz': <PhysicalUnit kHz>,
     'kJ': <PhysicalUnit kJ>,
     'kK': <PhysicalUnit kK>,
     'kN': <PhysicalUnit kN>,
     'kOhm': <PhysicalUnit kOhm>,
     'kPa': <PhysicalUnit kPa>,
     'kS': <PhysicalUnit kS>,
     'kT': <PhysicalUnit kT>,
     'kV': <PhysicalUnit kV>,
     'kW': <PhysicalUnit kW>,
     'kWb': <PhysicalUnit kWb>,
     'kcd': <PhysicalUnit kcd>,
     'kg': <PhysicalUnit kg>,
     'klm': <PhysicalUnit klm>,
     'klx': <PhysicalUnit klx>,
     'km': <PhysicalUnit km>,
     'kmol': <PhysicalUnit kmol>,
     'krad': <PhysicalUnit krad>,
     'ks': <PhysicalUnit ks>,
     'ksr': <PhysicalUnit ksr>,
     'lm': <PhysicalUnit lm>,
     'lx': <PhysicalUnit lx>,
     'm': <PhysicalUnit m>,
     'mA': <PhysicalUnit mA>,
     'mC': <PhysicalUnit mC>,
     'mF': <PhysicalUnit mF>,
     'mH': <PhysicalUnit mH>,
     'mHz': <PhysicalUnit mHz>,
     'mJ': <PhysicalUnit mJ>,
     'mK': <PhysicalUnit mK>,
     'mN': <PhysicalUnit mN>,
     'mOhm': <PhysicalUnit mOhm>,
     'mPa': <PhysicalUnit mPa>,
     'mS': <PhysicalUnit mS>,
     'mT': <PhysicalUnit mT>,
     'mV': <PhysicalUnit mV>,
     'mW': <PhysicalUnit mW>,
     'mWb': <PhysicalUnit mWb>,
     'mcd': <PhysicalUnit mcd>,
     'mg': <PhysicalUnit mg>,
     'min': <PhysicalUnit min>,
     'mlm': <PhysicalUnit mlm>,
     'mlx': <PhysicalUnit mlx>,
     'mm': <PhysicalUnit mm>,
     'mmol': <PhysicalUnit mmol>,
     'mol': <PhysicalUnit mol>,
     'mrad': <PhysicalUnit mrad>,
     'ms': <PhysicalUnit ms>,
     'msr': <PhysicalUnit msr>,
     'nA': <PhysicalUnit nA>,
     'nC': <PhysicalUnit nC>,
     'nF': <PhysicalUnit nF>,
     'nH': <PhysicalUnit nH>,
     'nHz': <PhysicalUnit nHz>,
     'nJ': <PhysicalUnit nJ>,
     'nK': <PhysicalUnit nK>,
     'nN': <PhysicalUnit nN>,
     'nOhm': <PhysicalUnit nOhm>,
     'nPa': <PhysicalUnit nPa>,
     'nS': <PhysicalUnit nS>,
     'nT': <PhysicalUnit nT>,
     'nV': <PhysicalUnit nV>,
     'nW': <PhysicalUnit nW>,
     'nWb': <PhysicalUnit nWb>,
     'ncd': <PhysicalUnit ncd>,
     'ng': <PhysicalUnit ng>,
     'nlm': <PhysicalUnit nlm>,
     'nlx': <PhysicalUnit nlx>,
     'nm': <PhysicalUnit nm>,
     'nmol': <PhysicalUnit nmol>,
     'nrad': <PhysicalUnit nrad>,
     'ns': <PhysicalUnit ns>,
     'nsr': <PhysicalUnit nsr>,
     'pA': <PhysicalUnit pA>,
     'pC': <PhysicalUnit pC>,
     'pF': <PhysicalUnit pF>,
     'pH': <PhysicalUnit pH>,
     'pHz': <PhysicalUnit pHz>,
     'pJ': <PhysicalUnit pJ>,
     'pK': <PhysicalUnit pK>,
     'pN': <PhysicalUnit pN>,
     'pOhm': <PhysicalUnit pOhm>,
     'pPa': <PhysicalUnit pPa>,
     'pS': <PhysicalUnit pS>,
     'pT': <PhysicalUnit pT>,
     'pV': <PhysicalUnit pV>,
     'pW': <PhysicalUnit pW>,
     'pWb': <PhysicalUnit pWb>,
     'pcd': <PhysicalUnit pcd>,
     'pg': <PhysicalUnit pg>,
     'plm': <PhysicalUnit plm>,
     'plx': <PhysicalUnit plx>,
     'pm': <PhysicalUnit pm>,
     'pmol': <PhysicalUnit pmol>,
     'prad': <PhysicalUnit prad>,
     'ps': <PhysicalUnit ps>,
     'psr': <PhysicalUnit psr>,
     'rad': <PhysicalUnit rad>,
     's': <PhysicalUnit s>,
     'sr': <PhysicalUnit sr>,
     'uA': <PhysicalUnit uA>,
     'uC': <PhysicalUnit uC>,
     'uF': <PhysicalUnit uF>,
     'uH': <PhysicalUnit uH>,
     'uHz': <PhysicalUnit uHz>,
     'uJ': <PhysicalUnit uJ>,
     'uK': <PhysicalUnit uK>,
     'uN': <PhysicalUnit uN>,
     'uOhm': <PhysicalUnit uOhm>,
     'uPa': <PhysicalUnit uPa>,
     'uS': <PhysicalUnit uS>,
     'uT': <PhysicalUnit uT>,
     'uV': <PhysicalUnit uV>,
     'uW': <PhysicalUnit uW>,
     'uWb': <PhysicalUnit uWb>,
     'ucd': <PhysicalUnit ucd>,
     'ug': <PhysicalUnit ug>,
     'ulm': <PhysicalUnit ulm>,
     'ulx': <PhysicalUnit ulx>,
     'um': <PhysicalUnit um>,
     'umol': <PhysicalUnit umol>,
     'urad': <PhysicalUnit urad>,
     'us': <PhysicalUnit us>,
     'usr': <PhysicalUnit usr>}