fpraktikum/tem/auswertung/utility.py
2020-02-10 11:13:36 +01:00

325 lines
9.4 KiB
Python

import numpy.fft as fft
import numpy as np
import matplotlib.pyplot as plt
from scipy.optimize import root_scalar
import matplotlib
import matplotlib.ticker as ticker
import os
import re
from SecondaryValue import SecondaryValue
from scipy.optimize import curve_fit
from scipy.signal import find_peaks
###############################################################################
# Auxiliary #
###############################################################################
def normalize(array):
tmp = array.copy()
tmp = tmp - tmp.min()
return tmp/tmp.max()
def load_profiles(path):
"""Parses the measured Gold profiles.
:param path: path to the log
:returns: numpy array, (x, amplitude)
"""
skip = 0
with open(path, 'r') as f:
for line in f:
if 'Values' in line:
break
skip += 1
data = np.loadtxt(path, encoding='latin1', dtype=np.float, skiprows=skip + 1)
data[:, 1] = normalize(data[:, 1])
return data
def scientific_round(val, *err):
"""Scientifically rounds the values to the given errors."""
val, err = np.asarray(val), np.asarray(err)
if len(err.shape) == 1:
err = np.array([err])
err = err.T
err = err.T
if err.size == 1 and val.size > 1:
err = np.ones_like(val)*err
if len(err.shape) == 0:
err = np.array([err])
if val.size == 1 and err.shape[0] > 1:
val = np.ones_like(err)*val
i = np.floor(np.log10(err))
first_digit = (err // 10**i).astype(int)
prec = (-i + np.ones_like(err) * (first_digit <= 3)).astype(int)
prec = np.max(prec, axis=1)
def smart_round(value, precision):
value = np.round(value, precision)
if precision <= 0:
value = value.astype(int)
return value
if val.size > 1:
rounded = np.empty_like(val)
rounded_err = np.empty_like(err)
for n, (value, error, precision) in enumerate(zip(val, err, prec)):
rounded[n] = smart_round(value, precision)
rounded_err[n] = smart_round(error, precision)
return rounded, rounded_err
else:
prec = prec[0]
return smart_round(val, prec), *smart_round(err, prec)[0]
###############################################################################
# Plot Porn #
###############################################################################
matplotlib.rcParams.update({
'font.family': 'serif',
'text.usetex': False,
'pgf.rcfonts': False,
})
def pinmp_ticks(axis, ticks):
axis.set_major_locator(ticker.MaxNLocator(ticks))
axis.set_minor_locator(ticker.MaxNLocator(ticks*10))
return axis
def set_up_plot(ticks=10, pimp_top=True, subplot=111, fig=None):
if fig is None:
fig = plt.figure()
ax = fig.add_subplot(subplot)
pinmp_ticks(ax.xaxis, ticks)
pinmp_ticks(ax.yaxis, ticks)
ax.grid(which='minor', alpha=.3)
ax.grid(which='major', alpha=.8)
if pimp_top:
ax.tick_params(right=True, top=True, which='both')
else:
ax.tick_params(right=True, which='both')
return fig, ax
def save_fig(fig, title, folder='unsorted', size=(5, 4)):
fig.set_size_inches(*size)
fig.tight_layout()
try:
os.makedirs(f'./figs/{folder}/')
except OSError as exc:
pass
fig.savefig(f'./figs/{folder}/{title}.pdf')
fig.savefig(f'./figs/{folder}/{title}.pgf')
with open('./out/figlist.txt', 'a') as f:
f.write(r'''
\begin{figure}[H]\centering
\input{../auswertung/figs/'''
+ f'{folder}/{title}.pgf' +
r'''}
\caption{}
\label{fig:''' + folder + '-' + title + r'''}
\end{figure}
''')
def plot_profile_common(profile, **pyplot_args):
x, amp = profile.T
fig, ax = set_up_plot()
ax.step(x, amp, label='Intensität', **pyplot_args)
ax.set_xlim([x[0], x[-1]])
ax.set_ylabel('relative Intensit\"a')
ax.legend()
return fig, ax
def plot_profile(profile, **pyplot_args):
fig, ax = plot_profile_common(profile, **pyplot_args)
ax.set_xlabel('x [nm]')
return fig, ax
def plot_diffr_profile(profile, **pyplot_args):
fig, ax = plot_profile_common(profile, **pyplot_args)
ax.set_xlabel('x [1/nm]')
return fig, ax
def analyze_diffr_profile(profile, limits, chosen_indices=[], save=None,
**peak_args):
x, amp = profile.T
fig, ax = plot_diffr_profile(profile)
peaks, peak_info = find_peaks(amp[limits[0]:limits[1]], width=0, **peak_args)
peaks = peaks[chosen_indices]
widths = peak_info['widths'][chosen_indices]
peaks += limits[0]
ax.plot(x[peaks], amp[peaks], "x", label='Peaks')
ax.axvspan(x[limits[0]], x[limits[1]], color='gray', zorder=-1, alpha=.2,
label='Auswertungsbereich')
ax.legend()
for i, peak in enumerate(peaks):
ax.annotate(str(i+1), xy=(x[peak], amp[peak]), textcoords='offset points', xytext=(-3, 5))
if save:
save_fig(fig, *save)
candidates = 1/x[peaks]
d_candidates = candidates**2*(x[1]-x[0])
sigma_candidates = candidates**2*widths*(x[1]-x[0])/(2.355) # correct for width
return candidates, d_candidates, sigma_candidates
def analyze_profile(profile, limits=(0, -1), save=None, **peak_args):
x, amp = profile.T
fig, ax = plot_profile(profile)
peaks, _ = find_peaks(amp[limits[0]:limits[1]], **peak_args)
peaks += limits[0]
ax.plot(x[peaks], amp[peaks], "x", label='Peaks')
ax.axvspan(x[limits[0]], x[limits[1]], color='gray', zorder=-1, alpha=.2,
label='Auswertungsbereich')
ax.legend()
dx = (x[1] - x[0])
numpeaks = peaks.size - 1
sigma = (x[peaks[1:]] - x[peaks[:-1]]).std()/np.sqrt(numpeaks)
l = (x[peaks[-1]] - x[peaks[0]])/numpeaks
dl = np.sqrt(2)*dx/numpeaks
if save:
save_fig(fig, *save)
return l, dl, sigma
def find_miller_indices(squares):
squares = np.asarray(squares)
if squares.size > 1:
return np.array([find_miller_indices(x) for x in squares])
square = squares
return np.array([(a, b, c) for (a, b, c) \
in np.ndindex((square+1, square+1, square+1)) \
if (a % 2 + b % 2 + c % 2) in (0, 3) and a**2 + b**2 + c**2 == square and a >= b >= c])
def can_be_sum_of_squares(square):
for a, b, c in np.ndindex((square+1, square+1, square+1)):
if (a % 2 + b % 2 + c % 2) in (0, 3) and a**2 + b**2 + c**2 == square:
return True
return False
def generate_miller_table(squares):
squares = np.unique(squares)
inds = find_miller_indices(squares)
out = ''
for i, ind_list in zip(squares, inds):
out += r'\(\sqrt{' + str(i) + r'}\) & '
for ind in ind_list:
out += r'\(\mqty(' + ' & '.join(ind.astype(str)) + r')\), '
out = out[:-2]
out += r' \\' + '\n'
return out
def evaluate_hypothesis(analyzed, maximum=10, gold=.4078, hints=[]):
diffs = np.empty((maximum, analyzed.shape[0]))
squared_ds = np.array([x for x in np.arange(1, maximum + 1, 1) \
if can_be_sum_of_squares(x)])
ds = np.sqrt(squared_ds)
a = analyzed[:,0][:, None] * ds[None, :]
gold = a[0,0]
diff = np.abs(a - gold)
mindiff = np.argmin(diff, axis=1)
for peak, ds_hint in hints:
mindiff[peak] = np.where(squared_ds == ds_hint)[0]
# thats ugly!
return squared_ds[mindiff], analyzed[:]*ds[mindiff,None], np.abs((analyzed[:]*ds[mindiff,None])[:, 0] - gold)
def generate_analysis_table(analyzed):
out = ''
for i, val in enumerate(analyzed):
val = np.array(scientific_round(*val))
out += f'{i + 1} & ' + ' & '.join(val.astype(str)) + ' \\\\\n'
return out
def generate_hypethsesis_table(squared, analyzed, residues):
out = ''
for i, square, value, residue in zip(range(1, len(squared)+1),
squared, analyzed, residues):
value = np.array(scientific_round(*value))
out += rf'{i} & \(\sqrt{{{square}}}\) & ' \
+ ' & '.join(value.astype(str)) + f' & {residue:.3f} \\\\\n'
return out
def determine_lattice_constant(hypothesis):
"""
Calculate the weighted mean and standard deviation by using the
combined deviation as weights.
The systemic deviation is calculated by error propagation.
"""
a_s = hypothesis[1][:,0]
syst_err = hypothesis[1][:,1] + hypothesis[1][:,2]
weights = 1/syst_err**2
a = np.average(a_s, weights=weights)
d_a = np.sqrt(1/np.sum(weights))
sigma_a = np.sqrt(np.average((a_s-a)**2, weights=weights))
return a, d_a, sigma_a
###############################################################################
# FFT Stuff #
###############################################################################
import cv2
def get_image_fft_mag(image):
f = np.fft.fft2(image)
fshift = np.fft.fftshift(f)
magnitude_spectrum = 20*np.log(np.abs(fshift))
return magnitude_spectrum
def plot_images_fft(paths, labels, cmap='gray', save=None):
fig, axes = plt.subplots(1, len(paths))
for path, label, ax in zip(paths, labels, axes):
img = cv2.imread(path, 0)
fft = get_image_fft_mag(img)
ax.set_xticks([])
ax.set_yticks([])
ax.imshow(fft, cmap=cmap)
ax.set_title('FFT ' + label)
if save:
save_fig(fig, *save)
return fig, axes