sncosmo.BandpassInterpolator

class sncosmo.BandpassInterpolator(transmissions, dependent_transmissions, prefactor=1.0, name=None)

Bandpass generator defined as a function of focal plane position.

Instances of this class are not Bandpasses themselves, but generate Bandpasses at a given focal plane position. This class stores the transmission as a function of focal plane position and interpolates between the defined positions to return the bandpass at an arbitrary position.

Parameters:

transmissionslist of (wave, trans) pairs

Transmissions that apply everywhere in the focal plane.

dependent_transmissionslist of (value, wave, trans)

Transmissions that depend on some parameter. Each value is the scalar parameter value, wave and trans are 1-d arrays.

prefactorfloat, optional

Scalar multiplying factor.

namestr

Examples

Transmission uniform across focal plane:

>>> uniform_trans = ([4000., 5000.], [1., 0.5])  # wave, trans

Transmissions as a function of radius:

>>> trans0 = (0., [4000., 5000.], [0.5, 0.5])  # radius=0
>>> trans1 = (1., [4000., 5000.], [0.75, 0.75]) # radius=1
>>> trans2 = (2., [4000., 5000.], [0.1, 0.1]) # radius=2

>>> band_interp = BandpassInterpolator([uniform_trans],
...                                    [trans0, trans1, trans2],
...                                    name='my_band')

Min and max radius:

>>> band_interp.minpos(), band_interp.maxpos()
(0.0, 2.0)

Get bandpass at a given radius:

>>> band = band_interp.at(1.5)

>>> band
<AggregateBandpass 'my_band at 1.500000' at 0x7f7a2e425668>

The band is aggregate of uniform transmission part, and interpolated radial-dependent part.

>>> band([4500., 4600.])
array([ 0.65625,  0.6125 ])

__init__(transmissions, dependent_transmissions, prefactor=1.0, name=None)

Methods

__init__(transmissions, dependent_transmissions)
at(pos)	Return the bandpass at the given position
maxpos()	Maximum positional parameter value.
minpos()	Minimum positional parameter value.