def get_fft(self, window=None, subtract_last=True):
"""Returns Fourier transform of the whole evolution superoperator
Parameters
----------
window: DFunction or numpy array
Windowing function by which the data are multiplied
subtract_last: bool
If True, the value at the last available time is subtracted
from all times
"""
if window is None:
winfce = qr.DFunction(self.time,
numpy.ones(self.time.length, dtype=qr.REAL))
else:
winfce = window
dat = self.data
if subtract_last:
dat = dat - dat[-1, :, :, :, :]
# FIXME: Implement windowing
fdat = numpy.fft.ifft(dat, axis=0) #*winfce.data)
fdat = numpy.fft.fftshift(fdat, axes=0)
time = self.time
freq = time.get_FrequencyAxis()
return fdat, freq
def get_element_fft(self, elem, window=None):
"""Returns a DFunction with the FFT of the element evolution
"""
if window is None:
winfce = qr.DFunction(self.time,
numpy.ones(self.time.length, dtype=qr.REAL))
else:
winfce = window
dat = self.data[:, elem[0], elem[1], elem[2], elem[3]]
fdat = numpy.fft.ifft(dat * winfce.data)
fdat = numpy.fft.fftshift(fdat)
time = self.time
freq = time.get_FrequencyAxis()
ffce = qr.DFunction(freq, fdat)
return ffce
def get_peak_cross_sections(V, twod_p):
cut_long = twod_p.get_cut_along_line(V[0], V[1])
cut_short1 = twod_p.get_cut_along_line(V[3], V[2])
cut_short2 = twod_p.get_cut_along_line(V[2], V[3])
data1 = np.array(cut_short1.data)
data2 = np.flip(np.array(cut_short2.data))
data3 = np.hstack((data1, data2))
shift = cut_short1.axis.data[1] + cut_short1.axis.data[-1]
cut_short2.axis.data = cut_short2.axis.data + shift
new_axis = np.hstack((cut_short1.axis.data, cut_short2.axis.data))
qr_axis = qr.ValueAxis(0.0, len(new_axis), new_axis[1])
short_final = qr.DFunction(qr_axis, data3)
data_max = (np.amax(twod_p.data))/2
long_p_1 = next(x for x, val in enumerate(cut_long.data) if val > (data_max))
for_lp2 = np.flip(cut_long.data)
long_p_2 = next(x for x, val in enumerate(for_lp2) if val > (data_max))
long_width = cut_long.axis.data[-long_p_2-1] - cut_long.axis.data[long_p_1]
short_p_1 = next(x for x, val in enumerate(short_final.data) if val > (data_max))
for_sp2 = np.flip(short_final.data)
short_p_2 = next(x for x, val in enumerate(for_sp2) if val > (data_max))
short_width = short_final.axis.data[-short_p_2-1] - short_final.axis.data[short_p_1]
fig, ax = plt.subplots(2)
ax[0].plot(cut_long.axis.data, cut_long.data)
ax[0].set_title('long')
ax[1].plot(short_final.axis.data, short_final.data)
ax[1].set_title('short')
plt.show()
return short_width, long_width
HH = m.get_Hamiltonian()
with qr.frequency_units("1/cm"):
print(HH)
a1.plot(axis=[11500, 12500, 0, numpy.max(a1.data) * 1.1])
save_load = False
if save_load:
filename = "abs_1mol_20cm_100fs_100K_m20"
with qr.frequency_units("1/cm"):
a1.save(filename, ext="dat")
with qr.frequency_units("1/cm"):
f = qr.DFunction()
f.load(filename, ext="dat", axis="frequency")
f.plot()
"""
Absorption of a simple dimer aggregate of two-level molecules
"""
ta = qr.TimeAxis(0.0, 2000, 5.0)
cfce_params1 = dict(ftype="OverdampedBrownian",
reorg=10.0,
f.plot(show=False)
plt.plot(x, ref_nexp(x, fitpar), "--g")
plt.show()
#
# Time axis on which we will fit
#
t = qr.TimeAxis(0.0, 1000, 1.0)
x = t.data
#
# Mono-exponential function
#
fv = single_exp(x)
f = qr.DFunction(t, fv)
# parameters a, b and c of a*exp(-b*t) + c
inpar = [1.5, 1.0 / 100.0, 0.1]
# This is how we use the `fit_exponential` function
fitpar = f.fit_exponential(guess=inpar)
test_exponential(x, f, inpar, fitpar)
#
# Bi-exponential function
#
fv = double_exp(x)
f = qr.DFunction(t, fv)
label="Electronic coherence")
plt.plot(timea.data,
numpy.abs(opt_cohS),
"-m",
label="Optical coherence")
plt.legend()
plt.title("Absolute value of coherences: site basis")
plt.show()
#
# Exponential fit of population decay
#
if _fit_:
if J != 0.0:
pop_e_f = qr.DFunction(timea, pop_e)
popt_p_e = pop_e_f.fit_exponential(guess=[0.5, 1.0 / 100, 0.3])
pop_s_f = qr.DFunction(timea, pop_s)
popt_p_s = pop_s_f.fit_exponential(guess=[0.5, 1.0 / 100, 0.3])
if _show_plots_:
# plot the fit
with qr.eigenbasis_of(ham):
plt.plot(timea.data,
pop_e,
"-k",
label="Population of exciton 2")
plt.plot(
timea.data,
popt_p_e[0] * numpy.exp(-popt_p_e[1] * timea.data) +
popt_p_e[2],