def __init__(self, config, RT):
MultiComponentSurface.__init__(self, config, RT)
self.statevec.extend(['GLINT'])
self.scale.extend([1.0])
self.init_val.extend([0.005])
self.bounds.extend([[0, 0.2]])
self.glint_ind = len(self.statevec) - 1
def __init__(self, config, RT):
MultiComponentSurface.__init__(self, config, RT)
# Handle additional state vector elements
self.statevec.extend(['SURF_TEMP_K'])
self.init_val.extend([270.0])
self.scale.extend([1000.0])
self.bounds.extend([[250.0, 2000.0]])
self.surf_temp_ind = len(self.statevec) - 1
# Treat emissive surfaces as a fractional blackbody
self.statevec.extend(['BB_MIX_FRAC'])
self.scale.extend([1.0])
self.init_val.extend([0.1])
self.bounds.extend([[0, 1]])
self.bb_frac_ind = len(self.statevec) - 1
def dlrfl_dx(self, x_surface, geom):
'''Partial derivative of Lambertian reflectance with respect to state
vector, calculated at x_surface.'''
dlrfl = MultiComponentSurface.dlrfl_dx(self, x_surface, geom)
dlrfl[:, self.bb_frac_ind] = 0
dlrfl[:, self.surf_temp_ind] = 0
return dlrfl
def Sa(self, x_surface, geom):
'''Covariance of prior distribution, calculated at state x. We find
the covariance in a normalized space (normalizing by z) and then un-
normalize the result for the calling function.'''
Cov = MultiComponentSurface.Sa(self, x_surface, geom)
f = s.array([[(10.0 * self.scale[self.glint_ind])**2]])
Cov[self.glint_ind, self.glint_ind] = f
return Cov
def Sa(self, x_surface, geom):
'''Covariance of prior distribution, calculated at state x'''
Cov = MultiComponentSurface.Sa(self, x_surface, geom)
t = s.array([[(10.0 * self.scale[self.surf_temp_ind])**2]])
Cov[self.surf_temp_ind, self.surf_temp_ind] = t
f = s.array([[(10.0 * self.scale[self.bb_frac_ind])**2]])
Cov[self.bb_frac_ind, self.bb_frac_ind] = f
return Cov
def xa(self, x_surface, geom):
'''Mean of prior distribution, calculated at state x. We find
the covariance in a normalized space (normalizing by z) and then un-
normalize the result for the calling function.'''
mu = MultiComponentSurface.xa(self, x_surface, geom)
mu[self.surf_temp_ind] = self.init_val[self.surf_temp_ind]
mu[self.bb_frac_ind] = self.init_val[self.bb_frac_ind]
return mu
def dLs_dx(self, x_surface, geom):
'''Partial derivative of surface emission with respect to state vector,
calculated at x_surface.'''
dLs_dx = MultiComponentSurface.dLs_dx(self, x_surface, geom)
T = x_surface[self.surf_temp_ind]
frac = x_surface[self.bb_frac_ind]
emissivity = s.ones(self.nwl, dtype=float)
Ls, dLs_dT = emissive_radiance(emissivity, T, self.wl)
dLs_dx[:, self.surf_temp_ind] = dLs_dT * frac
dLs_dx[:, self.bb_frac_ind] = Ls
return dLs_dx
def heuristic_surface(self, rfl_meas, Ls, geom):
'''Given a reflectance estimate and one or more emissive parameters,
fit a state vector.'''
glint_band = s.argmin(abs(900 - self.wl))
glint = s.mean(rfl_meas[(glint_band - 2):glint_band + 2])
water_band = s.argmin(abs(400 - self.wl))
water = s.mean(rfl_meas[(water_band - 2):water_band + 2])
if glint > 0.05 or water < glint:
glint = 0
glint = max(self.bounds[self.glint_ind][0] + eps,
min(self.bounds[self.glint_ind][1] - eps, glint))
lrfl_est = rfl_meas - glint
x = MultiComponentSurface.heuristic_surface(self, lrfl_est, Ls, geom)
x[self.glint_ind] = glint
return x
def heuristic_surface(self, rfl_meas, Ls, geom):
'''Given a reflectance estimate and one or more emissive parameters,
fit a state vector.'''
def err(z):
T, bb_frac = z
emissivity = s.ones(self.nwl, dtype=float)
Ls_est, d = emissive_radiance(emissivity, T, self.wl)
resid = Ls_est * bb_frac - Ls
return sum(resid**2)
x_surface = MultiComponentSurface.heuristic_surface(
self, rfl_meas, Ls, geom)
T, bb_frac = minimize(err, s.array([300, 0.1])).x
bb_frac = max(eps, min(bb_frac, 1.0 - eps))
T = max(self.bounds[-2][0] + eps, min(T, self.bounds[-2][1] - eps))
x_surface[self.bb_frac_ind] = bb_frac
x_surface[self.surf_temp_ind] = T
return x_surface
def __init__(self, config):
'''ForwardModel contains all the information about how to calculate
radiance measurements at a specific spectral calibration, given a
state vector. It also manages the distributions of unretrieved,
unknown parameters of the state vector (i.e. the S_b and K_b
matrices of Rodgers et al.'''
self.instrument = Instrument(config['instrument'])
# Build the radiative transfer model
if 'modtran_radiative_transfer' in config:
self.RT = ModtranRT(config['modtran_radiative_transfer'],
self.instrument)
elif 'libradtran_radiative_transfer' in config:
self.RT = LibRadTranRT(config['libradtran_radiative_transfer'],
self.instrument)
else:
raise ValueError('Must specify a valid radiative transfer model')
# Build the surface model
if 'surface' in config:
self.surface = Surface(config['surface'], self.RT)
elif 'multicomponent_surface' in config:
self.surface = MultiComponentSurface(
config['multicomponent_surface'], self.RT)
elif 'emissive_surface' in config:
self.surface = MixBBSurface(config['emissive_surface'], self.RT)
elif 'glint_surface' in config:
self.surface = GlintSurface(config['glint_surface'], self.RT)
elif 'iop_surface' in config:
self.surface = IOPSurface(config['iop_surface'], self.RT)
else:
raise ValueError('Must specify a valid surface model')
bounds, scale, init_val, statevec = [], [], [], []
# Build state vector for each part of our forward model
for name in ['surface', 'RT']:
obj = getattr(self, name)
inds = len(statevec) + s.arange(len(obj.statevec), dtype=int)
setattr(self, '%s_inds' % name, inds)
for b in obj.bounds:
bounds.append(deepcopy(b))
for c in obj.scale:
scale.append(deepcopy(c))
for v in obj.init_val:
init_val.append(deepcopy(v))
for v in obj.statevec:
statevec.append(deepcopy(v))
self.bounds = tuple(s.array(bounds).T)
self.scale = s.array(scale)
self.init_val = s.array(init_val)
self.statevec = statevec
self.wl = self.instrument.wl
# Capture unmodeled variables
bvec, bval = [], []
for name in ['RT', 'instrument', 'surface']:
obj = getattr(self, name)
inds = len(bvec) + s.arange(len(obj.bvec), dtype=int)
setattr(self, '%s_b_inds' % name, inds)
for b in obj.bval:
bval.append(deepcopy(b))
for v in obj.bvec:
bvec.append(deepcopy(v))
self.bvec = s.array(bvec)
self.bval = s.array(bval)
self.Sb = s.diagflat(pow(self.bval, 2))
return
def summarize(self, x_surface, geom):
'''Summary of state vector'''
return MultiComponentSurface.summarize(self, x_surface, geom) + \
' Glint: %5.3f' % x_surface[self.glint_ind]
def dlrfl_dx(self, x_surface, geom):
'''Partial derivative of reflectance with respect to state vector,
calculated at x_surface.'''
return MultiComponentSurface.dlrfl_dx(self, x_surface, geom)
def calc_lrfl(self, x_surface, geom):
'''Lambertian-equivalent reflectance'''
return MultiComponentSurface.calc_lrfl(self, x_surface, geom)
def xa(self, x_surface, geom):
'''Mean of prior distribution, calculated at state x.'''
mu = MultiComponentSurface.xa(self, x_surface, geom)
mu[self.glint_ind] = self.init_val[self.glint_ind]
return mu
def summarize(self, x_surface, geom):
'''Summary of state vector'''
mcm = MultiComponentSurface.summarize(self, x_surface, geom)
msg = ' Kelvins: %5.1f BlackBody Fraction %4.2f ' % tuple(
x_surface[-2:])
return msg + mcm
def calc_lamb(self, x_surface, geom):
'''Lambertian Reflectance'''
return MultiComponentSurface.calc_lamb(self, x_surface, geom)