def test_spectrum_invalid_energies():
"""Test if function `plot.spectrum` raises a ``ValueError`` when the number of sampled energies
is less than two"""
with pytest.raises(
ValueError,
match="Number of sampled energies must be at least two"):
plot.spectrum([1000.0])
def run_and_create(n):
inputfile = open('./Task2Code/input_for_exercise3.txt', "r")
N = int(inputfile.readline()) #Number of Atoms
nmodes = 3 * N - 6 #Number of Modes
w = np.zeros(nmodes, float) #vib. frequencies of ground electronic state
wp = np.zeros(nmodes, float) #vib. frequencies of excited electronic state
Ud = np.zeros((nmodes, nmodes), float) #Duschinsky Matrix
delta = np.zeros(nmodes, float) #Displacement Vector
###############################
##### READ IN PARAMETERS ######
###############################
for i in range(nmodes):
w[i] = float(inputfile.readline())
for i in range(nmodes):
wp[i] = float(inputfile.readline())
for i in range(nmodes):
for j in range(nmodes):
Ud[i, j] = float(inputfile.readline())
for i in range(nmodes):
delta[i] = float(inputfile.readline())
T = 500 # temperature
#####################################
##### CALCULATE GBS PARAMETERS ######
#####################################
t, U1, r, U2, alpha = vibronic.gbs_params(w, wp, Ud, delta, T)
###############################
###### GENERATE SAMPLES #######
###############################
nr_samples = n
s = sample.vibronic(t, U1, r, U2, alpha, nr_samples)
e = vibronic.energies(s, w, wp)
###############################
######## PLOT SPECTRUM ########
###############################
spectrum = plot.spectrum(e, xmin=-300, xmax=2000)
offline.plot(spectrum, filename="spectrum_{}_samples.html".format(n))
print(np.around(e[:5], 4)) # 4 decimal precision ############################################################################## # Once the GBS parameters have been obtained, it is straightforward to run the GBS algorithm: we # generate many samples, compute their energies, and make a histogram of the observed energies. # The :mod:`~.apps.sample` module contains the function :func:`~.vibronic`, which is tailored for # use in vibronic spectra applications. Similarly, the :mod:`~.apps.plot` module includes a # :func:`~.spectrum` function that generates the vibronic spectrum from the GBS samples. Let's see # how this is done for just a few samples: from strawberryfields.apps import sample, plot import plotly nr_samples = 10 s = sample.vibronic(t, U1, r, U2, alpha, nr_samples) e = vibronic.energies(s, w, wp) spectrum = plot.spectrum(e, xmin=-1000, xmax=8000) plotly.offline.plot(spectrum, filename="spectrum.html") ############################################################################## # .. raw:: html # :file: ../../examples_apps/spectrum.html # # .. note:: # The command ``plotly.offline.plot()`` is used to display plots in the documentation. In # practice, you can simply use ``spectrum.show()`` to generate the figure. ############################################################################## # The bars in the plot are the histogram of energies. The curve surrounding them is a Lorentzian # broadening of the spectrum, which better represents the observations from an actual experiment. # Of course, 10 samples are not enough to accurately reconstruct the vibronic spectrum. Let's # instead use the 20,000 pre-generated samples from the :mod:`~.apps.data` module.
for i in range(nmodes):
for j in range(nmodes):
Ud[i,j]=float(inputfile.readline())
for i in range(nmodes):
delta[i]=float(inputfile.readline())
T = 500 # temperature
#####################################
##### CALCULATE GBS PARAMETERS ######
#####################################
t, U1, r, U2, alpha = vibronic.gbs_params(w, wp, Ud, delta, T)
###############################
###### GENERATE SAMPLES #######
###############################
nr_samples = 20000
s = sample.vibronic(t, U1, r, U2, alpha, nr_samples)
e = vibronic.energies(s, w, wp)
###############################
######## PLOT SPECTRUM ########
###############################
spectrum = plot.spectrum(e, xmin=-300, xmax=2000)
offline.plot(spectrum, filename="spectrum.html")