def degree_distribution(A, networkName, directed=True):
binNum = 30
if (directed):
(kin, kout) = get_degree(A)
bins = np.linspace(0, np.log10(np.max(kin)), num=binNum)
digitized = np.digitize(np.log10(kin), bins)
bin_counts = np.asarray([digitized.tolist().count(i) for i in range(0,len(bins))])
bin_counts = ma.log10(bin_counts)
#fit the line
a,b = ma.polyfit(bins, bin_counts, 1, full=False)
print('best fit in degree line:\ny = {:.2f} + {:.2f}x'.format(b, a))
yfit = [b + a * xi for xi in bins]
fig, axs = plt.subplots(2, 1)
axs[0].scatter(bins, bin_counts)
axs[0].plot(bins, yfit, color="orange")
axs[0].set_title('in-degree distribution')
axs[0].set_xlabel('Degree (d) log base 10', fontsize="small")
axs[0].set_ylabel('Frequency log base 10', fontsize="small")
axs[0].set_ylim(bottom=0)
bins = np.linspace(0, np.log10(np.max(kout)), num=binNum)
digitized = np.digitize(np.log10(kout), bins)
bin_counts = np.asarray([digitized.tolist().count(i) for i in range(0,len(bins))])
bin_counts = ma.log10(bin_counts)
print('best fit out degree line:\ny = {:.2f} + {:.2f}x'.format(b, a))
yfit = [b + a * xi for xi in bins]
axs[1].scatter(bins, bin_counts)
axs[1].plot(bins, yfit, color="orange")
axs[1].set_title('out-degree distribution')
axs[1].set_xlabel('Degree (d) log base 10', fontsize="small")
axs[1].set_ylabel('Frequency log base 10', fontsize="small")
plt.subplots_adjust(hspace=0.01)
plt.tight_layout()
plt.savefig(networkName + 'degree.pdf')
plt.close()
if (not directed):
(kin,kout) = get_degree(A)
print (kin.shape)
#bin the statistics
bins = np.linspace(0, np.log10(np.max(kin)), num=binNum)
digitized = np.digitize(np.log10(kin), bins)
bin_counts = np.asarray([digitized.tolist().count(i) for i in range(0,len(bins))])
bin_counts = ma.log10(bin_counts)
#fit the line
a,b = ma.polyfit(bins, bin_counts, 1, full=False)
print('best fit line:\ny = {:.2f} + {:.2f}x'.format(b, a))
yfit = [b + a * xi for xi in bins]
plt.scatter(bins, bin_counts)
plt.plot(bins, yfit, color="orange")
plt.title('degree distribution')
plt.xlabel('Degree (d) log base 10', fontsize="small")
plt.ylabel('Frequency log base 10', fontsize="small")
plt.ylim(bottom=0)
# plt.xscale('log')
# plt.yscale('log')
plt.tight_layout()
plt.savefig(networkName + 'degree.pdf')
plt.close()
def my_polyfit(x, y, deg, degatt=0):
k = ma.polyfit(x, y, degatt)
res = my_poly(k, x)
resid = ma.abs(res - y)
medresid = ma.median(resid, axis=0)
if y.ndim != 1:
mask = ma.logical_not(ma.sum((resid > 3 * medresid), axis=1).astype('bool'))
else:
mask = (resid < 3 * medresid)
y = y[mask]
x = x[mask]
k = ma.polyfit(x, y, deg)
return(k, mask)
def rate_of_change_polyfit(data, period, dates, fit_length=1):
'''This function calculates a rate of change in the same way as the old code did, using successive lines of best fit'''
import aux_functions
import numpy as np
import numpy.ma as ma
seconds_in_day = 8.64e4
tolerance = 0.95
numbers = np.array([aux_functions.datetime_to_float(ddt) for ddt in dates])
dates_within = [
ddt for ddt in dates if ddt >= period[0] and ddt <= period[1]
]
output_series = ma.masked_array(np.zeros(len(dates_within)),
mask=np.zeros(len(dates_within),
dtype='bool'))
for (idate, ddt) in enumerate(dates_within):
number = aux_functions.datetime_to_float(ddt)
index_period = np.where(
np.logical_and(numbers >= number - fit_length,
numbers <= number + fit_length))
numbers_period = numbers[index_period]
data_period = data[index_period]
if np.sum(data_period.mask) / data_period.shape[0] > tolerance:
output_series.mask.itemset(idate, True)
else:
rate_of_change_instance = ma.polyfit(numbers_period, data_period,
1)[0] / seconds_in_day
output_series.data.itemset(idate, rate_of_change_instance)
return output_series
def baseline_and_deglitch(orig_spec,
ww=300,
sigma_cut=4.,
poly_n=2.,
filt_width=7.):
"""
(1) Calculate a rolling standard deviation (s) in a window
of 2*ww pixels
(2) Mask out portions of the spectrum where s is more than
sigma_cut times the median value for s.
(3) Fit and subtract-out a polynomial of order poly_n
(currently hard-coded to 2)
(4) Median filter (with a filter width of filt_width)
to remove the single-channel spikes seen.
"""
ya = rolling_window(orig_spec,ww*2)
#Calculate standard dev and pad the output
stds = my_pad.pad(np.std(ya,-1),(ww-1,ww),mode='edge')
#Figure out which bits of the spectrum have signal/glitches
med_std = np.median(stds)
std_std = np.std(stds)
sigma_x_bar = med_std/np.sqrt(ww)
sigma_s = (1./np.sqrt(2.))*sigma_x_bar
#Mask out signal for baseline
masked = ma.masked_where(stds > med_std+sigma_cut*sigma_s,orig_spec)
xx = np.arange(masked.size)
ya = ma.polyfit(xx,masked,2)
baseline = ya[0]*xx**2+ya[1]*xx+ya[2]
sub = orig_spec-baseline
#Filter out glitches in baseline-subtracted version
final = im.median_filter(sub,filt_width)[::filt_width]
return(final)
def fit_baseline(masked,xx,ndeg=2):
"""
Fit a polynomial baseline of
arbitrary (ndeg) order.
"""
ya = ma.polyfit(xx,masked,ndeg)
basepoly = np.poly1d(ya)
return(basepoly)
def ptc_irffpairs(imagelist, *coor, **kargs):
"""
TODO: Need to be finished !!
NHA
Perform ptc plot for pairs of ff at same level.
The pairs of ff should have the same light level.
The first 2 images must be bias
To eliminate the FPN, the 'shotnoise' image is computed as the subtraction
of two debiased flat field images
optional kargs arguments:
FACTOR (default = 2.0)
FIRST_FITTING (default = False)
LIMIT (default = False)
VERBOSE (default=False)
TODO: add Rotation by 90deg as an option
"""
x1, x2, y1, y2 = imagelist[0].get_windowcoor(*coor)
# Define empty list to store values
signal = []
stddev = []
variance = []
oddimageindex = list(range(1, len(imagelist), 2))
evenimageindex = list(range(0, len(imagelist), 2))
# For all pairs, compute signal, std and variance
for odd, even in zip(oddimageindex, evenimageindex):
ff1 = imagelist[odd]
ff2 = imagelist[even]
ffmean = (ff1 + ff2) / 2.0
shotnoise = ff1 - ff2
signal.append(np.mean(ffmean[x1:x2, y1:y2]))
variance.append(np.var(shotnoise[x1:x2, y1:y2]) / 2.0)
stddev.append(np.std(shotnoise[x1:x2, y1:y2]) / np.sqrt(2.0))
print(f"Signal: {signal[-1]} Variance: {variance[-1]}")
coefts = ma.polyfit(signal, variance, 1)
# coefts=ma.polyfit(signal[:-3],variance[:-3],1)
polyts = coefts[0] * np.array(signal) + coefts[1]
print(1 / coefts[0], coefts[1])
# plot variance v/s signal
plt.figure()
# plot(meansig,masked_variance,'b.')
plt.plot(signal, variance, 'b.')
plt.plot(signal, polyts, 'r-')
def get_poly_baseline(mspec, k_est, debug=True, **kwargs):
"""
Fit for the best polynomial baseline according to BIC
Search polynomial fits from order 0 to order 7 and
use the BIC to select the best fit. This fit should
also have an rms error within a factor of two of
the estimated noise (k_est). If this is not the case
then the baseline fit is most likely bad.
"""
d = np.arange(0, 7)
rms_err = np.zeros(d.shape)
all_polys = []
#k_est = 0.2/np.sqrt(7)
xx = np.arange(mspec.size)
yy = mspec
for i in range(len(d)):
p = ma.polyfit(xx, yy, d[i])
basepoly = P(p[::-1])
all_polys.append(basepoly)
rms_err[i] = np.sqrt(np.sum((basepoly(xx) - yy)**2) / len(yy))
BIC = np.sqrt(len(yy)) * rms_err / k_est + 1 * d * np.log(len(yy))
AIC = np.sqrt(len(yy)) * rms_err / k_est + 2 * d + 2 * d * (d + 1) / (
len(yy) - d - 1)
if debug:
fig = plt.figure(figsize=(12, 5))
ax = fig.add_subplot(311)
ax.plot(d, rms_err, '-k', label='rms-err')
ax.legend(loc=2)
ax.axhline(k_est * 2., ls=":", color='r')
ax.axhline(k_est, color='red')
ax.axhline(k_est / 2., ls=':', color='r')
ax = fig.add_subplot(312)
ax.plot(d, BIC, '-k', label='BIC')
ax.legend(loc=2)
ax = fig.add_subplot(313)
ax.plot(d, AIC, '-r', label='AIC')
ax.legend(loc=2)
plt.savefig(kwargs["outdir"] + "/debugplot.png")
plt.close(fig)
best_poly_order = np.argmin(AIC)
best_poly = all_polys[best_poly_order]
return (best_poly(xx))
def ptcloglog(imagelist, *coor, **kargs):
"""
TODO: Need to be finished!!
Perform ptc plot for ff at different light levels
The first image must be a bias
The FPN is not elliminated. This curve should illustrate the diferent regions of a
tipical detector
"""
signal = []
variance = []
stddev = []
x1, x2, y1, y2 = imagelist[0].get_windowcoor(*coor)
print("No error")
# Read in bias
bias = imagelist[0]
# For all images, compute signal, std and variance
for image in imagelist[1:]:
ff = image
ff = ff - bias
signal.append(np.mean(ff[x1:x2, y1:y2]))
variance.append(np.var(ff[x1:x2, y1:y2]))
stddev.append(np.std(ff[x1:x2, y1:y2]))
print(f"Signal: {signal[-1]} Variance: {variance[-1]}")
coefts = ma.polyfit(signal[:-3], variance[:-3], 1)
polyts = coefts[0] * signal + coefts[1]
print(1 / coefts[0], coefts[1])
# plot variance v/s signal
plt.figure()
# plot(meansig,masked_variance,'b.')
# plot(signal, variance, 'b.')
# plot(signal[:-3],polyts[:-3],'r-')
# Plot the curves
plt.loglog(signal, stddev, 'r')
def masked_polyfit(myTime, data, order, mask, firstNan, fit=False):
'''
using standard polyfit
'''
maskedY = ma.masked_array(data, mask=mask)
full = np.where(firstNan > order)[0]
# initialize coef array
# coef = np.zeros((order+1, data.shape[1]))
coef = ma.zeros((order + 1, data.shape[1])) + np.NaN
coef.mask = np.ones(coef.shape)
coef.mask[:, full] = 0
if full.size > 0:
print('full shape', full.shape)
print('time shape', myTime.shape)
print('mask shape', mask.shape)
coef[:, full] = ma.polyfit(myTime, maskedY[:, full], order)
if fit:
fitX = np.tile(myTime, (data.shape[1], 1))
fit = np.polyval(coef, fitX.T)
return coef, fit
return coef
def two_layer_treatment(mvp_dict, x_sills, x_ranges):
"""Estimate g-prime and interface depth
Inputs
------
mvp_dict: dict
Used throughout this file
x_sills: 2-tuple of floats
x position of the start and end of the sill in kilometres
x_ranges: 2-tuple of floats
x position of location where output is applicable
For my transect:
first sill: x_sills = (48, 58), x_ranges = (0, 80)
second sill: x_sills = (75, 90), x_ranges = (65, 200)
Returns
-------
gprime : 1D array
g * delta_rho/rho
interface_depth : 1D array
Depth in metres of "two-layer" interface
"""
# Simplify names of commonly used variables
prho = mvp_dict['prho'].copy()
z_c = mvp_dict['z_c'].copy()
x = mvp_dict['dist_flat']
bottom = np.array(mvp_dict['bottom'])
sill_inds = np.where(np.logical_and(x > x_sills[0], x < x_sills[1]))[0]
# Find interface of mode-1 wave for each profile in sill_inds
rho_interfaces = np.zeros_like(sill_inds, dtype='float')
for i, ind in enumerate(sill_inds):
# Interpolate horizontal mode structure against density
f = interp1d(mvp_dict['hori_0'][ind, :], prho[ind, :])
# Find density of zero crossing of horizontal structure
rho_interfaces[i] = f(0)
rho_interface = np.nanmean(rho_interfaces)
# Find depth of rho_interface along transect
x_in, y_in, z_in = x, z_c, prho
interface_depth = get_contour(x_in, y_in, z_in, rho_interface)
# Preallocate results to keep
gprime = np.full_like(x_in, np.nan)
# Find average density in each layer using linear fit
for i, rho_i in enumerate(mvp_dict['prho']):
top_layer_inds = z_c <= interface_depth[i]
bot_layer_inds = z_c > interface_depth[i]
top_z = z_c[top_layer_inds]
bot_z = z_c[bot_layer_inds]
top_rho = prho[i, :][top_layer_inds]
bot_rho = prho[i, :][bot_layer_inds]
if (~top_rho.mask).sum() < 3 or (~bot_rho.mask).sum() < 3:
# Not enough values to do linear fit
continue
p_top = ma.polyfit(top_z, top_rho, 1)
p_bot = ma.polyfit(bot_z, bot_rho, 1)
top_rho_avg = np.polyval(p_top, interface_depth[i]/2)
bot_rho_avg = np.polyval(p_bot, (bottom[i] + interface_depth[i])/2)
gprime[i] = 9.81*(bot_rho_avg - top_rho_avg)/bot_rho_avg
# Remove output where inappropriate
inappropriate_inds = np.logical_or(x < x_ranges[0], x > x_ranges[1])
gprime[inappropriate_inds] = np.nan
interface_depth[inappropriate_inds] = np.nan
return rho_interface, gprime, interface_depth
def qqplot(data, distrib=ssd.norm, alpha=0.4, beta=0.4, fsp=None, plot_line=True, **kwargs):
"""
Returns a quantile-quantile plot with theoretical quantiles in abscissae, and
experimental quantiles in ordinates.
The experimental quantiles are estimated through the equation:
.. math::
q_i = \\frac{i-\\alpha}{n-\\alpha-\\beta}
where :math:`i` is the rank order statistic, :math:`n` the number of
unmasked data and :math:`\\alpha` and :math:`\\beta` two parameters between 0
and 1. The default :math:`\\alpha=\\beta=0.4` gives approximately unbiased
estimates of the quantiles.
Parameters
----------
data : array
Input data
distrib : {norm, function}, optional
Theoretical distribution used to compute the expected quantiles.
If None, use a normal distribution.
alpha : {float} optional
Coefficient for the computation of plotting positions.
beta : {float} optional
Coefficient for the computation of plotting positions.
fsp : {None, Subplot}, optional
Subplot where to plot. If None, use the current axe.
plot_line : {True, False}
Whether to compute a regression line.
Returns
-------
plotted : :class:`matplotlib.lines.Line2D`
Plotted data
lines : :class:`matplotlib.lines.Line2D`
Plotted regression line
(a,b) : tuple
Slope and intercept of the regression line.
Notes
-----
* The ``distrib`` parameter must be a function with a :meth:`.ppf` method.
* The input data is ravelled beforehand.
See Also
--------
scipy.stats.mstats.mquantiles
Computes quantiles from a population.
"""
data = np.ravel(data)
qq = qqcalc(data, distrib=distrib, alpha=alpha, beta=beta)
#
if fsp is None:
fsp = pyplot.gca()
if not len(kwargs):
kwargs.update(marker="o", c="k", ls="")
plotted = fsp.plot(qq, data, **kwargs)
#
if plot_line:
(a, b) = ma.polyfit(qq, data, 1)
xlims = fsp.get_xlim()
regline = np.polyval((a, b), xlims)
lines = fsp.plot(xlims, regline, "k:")
return (plotted, lines, (a, b))
return plotted
def qqplot(data,
distrib=ssd.norm,
alpha=.4,
beta=.4,
fsp=None,
plot_line=True,
**kwargs):
"""
Returns a quantile-quantile plot with theoretical quantiles in abscissae, and
experimental quantiles in ordinates.
The experimental quantiles are estimated through the equation:
.. math::
q_i = \\frac{i-\\alpha}{n-\\alpha-\\beta}
where :math:`i` is the rank order statistic, :math:`n` the number of
unmasked data and :math:`\\alpha` and :math:`\\beta` two parameters between 0
and 1. The default :math:`\\alpha=\\beta=0.4` gives approximately unbiased
estimates of the quantiles.
Parameters
----------
data : array
Input data
distrib : {norm, function}, optional
Theoretical distribution used to compute the expected quantiles.
If None, use a normal distribution.
alpha : {float} optional
Coefficient for the computation of plotting positions.
beta : {float} optional
Coefficient for the computation of plotting positions.
fsp : {None, Subplot}, optional
Subplot where to plot. If None, use the current axe.
plot_line : {True, False}
Whether to compute a regression line.
Returns
-------
plotted : :class:`matplotlib.lines.Line2D`
Plotted data
lines : :class:`matplotlib.lines.Line2D`
Plotted regression line
(a,b) : tuple
Slope and intercept of the regression line.
Notes
-----
* The ``distrib`` parameter must be a function with a :meth:`.ppf` method.
* The input data is ravelled beforehand.
See Also
--------
scipy.stats.mstats.mquantiles
Computes quantiles from a population.
"""
data = np.ravel(data)
qq = qqcalc(data, distrib=distrib, alpha=alpha, beta=beta)
#
if fsp is None:
fsp = pyplot.gca()
if not len(kwargs):
kwargs.update(marker='o', c='k', ls='')
plotted = fsp.plot(qq, data, **kwargs)
#
if plot_line:
(a, b) = ma.polyfit(qq, data, 1)
xlims = fsp.get_xlim()
regline = np.polyval((a, b), xlims)
lines = fsp.plot(xlims, regline, 'k:')
return (plotted, lines, (a, b))
return plotted
import numpy as np
import numpy.ma as ma
import matplotlib.pyplot as plt
data = np.loadtxt('faulty_data.dat')
plt.plot(data[:, 0], data[:, 1], 'o')
x = data[:, 0]
y = data[:, 1]
mask = y > 35
y_m = ma.masked_array(y, mask)
x_m = ma.masked_array(x, mask)
fit_orig = np.polyfit(x, y, 2)
fit_masked = ma.polyfit(x_m, y_m, 2)
x_i = np.linspace(-6, 6, 35)
plt.plot(x_i, np.polyval(fit_orig, x_i), label='original')
plt.plot(x_i, np.polyval(fit_masked, x_i), label='masked')
plt.legend()
plt.show()
def run(self,**keyval):
""" Method to calculate the continuum from the given masked spectrum.
If search=True is given as an argument then the algorithm will
iterate through the different order splines to find the best fit,
based on noise level.
Parameters
----------
keyval : dictionary
Dictionary containing the keyword value pair arguments
Returns
-------
numpy array containing the best fit continuum
Notes
-----
Arguments for the run method:
- search : bool, whether or not to search for the best fit. Default: False
- deg : int, the degree of polynomial to use, Defualt: 1
"""
# set up the data elements
args = {"x": self.x,
"y" : ma.fix_invalid(self.y,fill_value=0.0),
# reverse the weights since a masked array uses True for good values
# and UnivariateSpline needs a number. The reversal translates the
# True values to False, which are then interpreted as 0.0
"w" : -self.y.mask}
# get the given arguments
search = False
noise = None
chisq = 3.0
if "search" in keyval:
search = keyval["search"]
if "noise" in keyval:
noise = keyval["noise"]
if "chisq" in keyval:
maxchisq = keyval["chisq"]
for arg in ["deg"]:
if arg in keyval:
args[arg] = keyval[arg]
# if searching for the best fit
# limited to 3rd order as 4th and 5th order could fit weak wide lines
if search:
chisq = {0:1000.,
1:1000.,
2:1000.,
3:1000.}
# iterate over each possible order
for order in chisq:
args["deg"] = order
pfit = np.polyfit(**args)
if len(pfit) == 1:
numpar = 1
else:
# find the number of free parameters
# note that if a coefficient is << the max coefficient
# it is not considered a free parameter as it has very little affect on the fit
numpar = 0
mxpar = max(abs(pfit))
for i in range(len(pfit)):
if abs(mxpar/pfit[i]) < 1000.:
numpar += 1
fit = np.polyval(pfit,self.x)
chisq[order] = (stats.reducedchisquared(self.y, fit, numpar, noise), numpar)
# find the base fit, based on number of free parameters and chisq
mv = 1000.
order = 0
for k in chisq:
if chisq[k][0] < mv and (mv - chisq[k][0]) / mv > 0.2:
mv = chisq[k][0]
order = k
if mv > maxchisq:
logging.warning("No good fit for continuum found")
return None
args["deg"] = mv
logging.info("Using polynomial fit of order %i with chi^2 of %f" % (order, mv))
# do the final fit
pfit = np.polyfit(**args)
fit = np.polyval(pfit,self.x)
else:
# do the fit with the given parameters
pfit = ma.polyfit(**args)
fit = np.polyval(pfit,self.x)
return fit
