Source code for irfpy.jdc.flux0

''' A module to convert between the count rate and the flux for JDC.

A draft g-factor value is used, as in the proposal.
'''
import irfpy.jdc.energy0

class Flux2Count():
    ''' Flux is converted to count rate.
    '''
    def __init__(self):
        self.gfactor=5.6e-4
        self.etbl = irfpy.jdc.energy0.getEnergy()

    def getCounts(self, flux, energy_step):
        e_eV = self.etbl[energy_step]
        return self.getCounts_eV(flux, e_eV)

    def getCounts_eV(self, flux, energy_eV):
        '''

        :param flux: DIfferential flux in part. / cm2 sr eV s
        '''
        cps = self.gfactor * flux * energy_eV 
        return cps

class Count2Flux():
    ''' Count rate is converted to flux.
    '''
    def __init__(self):
        '''
        G-factor is constant, independent of anything.  5.6x10^-4 cm2 sr eV/eV.
        '''
        self.gfactor = 5.6e-4
        self.etbl = irfpy.jdc.energy0.getEnergy()

    def getFlux(self, cps, energy_step):
        ''' Depending on energy step, flux is calculated.

        Energy step is, as for the module consideration, 
        obtained from :mod:`irfpy.jdc.energy0`.

        >>> c2f = Count2Flux()
        >>> print('%.3f' % c2f.getFlux(1, 96))  # 1 count level for energy step 96.
        0.582
        '''
        e_eV = self.etbl[energy_step]

        return self.getFlux_eV(cps, e_eV)

    def getFlux_eV(self, cps, energy_eV):
        r''' Return the expected flux based on the absolute energy value.

        Based on the definition of the G-factor, one can get the
        conversion as

        .. math::

            J = \frac{C}{GE}

        where ``C`` is the countr ate in c/s, ``G`` is the g-factor
        in cm2 sr eV/eV, ``E`` is the energy in eV.
        The returned will be the differential flux in the unit of
        ``cnts / cm2 sr eV s``.

        >>> c2f = Count2Flux()
        >>> print('%.2f' % c2f.getFlux_eV(1, 1000))   # 1 count level for 1000eV channel.
        1.79
        '''
        return cps / self.gfactor / energy_eV



import unittest
import doctest


def doctests():
    return unittest.TestSuite((
        doctest.DocTestSuite(),
        ))
if __name__ == '__main__':
    unittest.main(defaultTest='doctests')