The default plot puts scientific notation in the x axis labels. These labels are 2,3,4, and 6, so that doesn't make much sense. Traditional methods seem to rely on the 'ScalarFormatter' which, is not used in log space...
import numpy as np
import matplotlib.pyplot as plt
from scipy.optimize import curve_fit
nu = np.array([34., 10., 3., 2., 1.])
bins = np.array([1.73619534, 2.6928761 , 3.64955685, 4.6062376 , 6.5195991 ])
x_err = (bins[2]-bins[1])/2*(nu/nu)
def func_powerlaw(x, m, c):
return x**m * c
target_func = func_powerlaw
popt, pcov = curve_fit(target_func, bins, nu, maxfev=2000, p0 = np.asarray([-1,34]))
perr = np.sqrt(np.diag(pcov))
x_line = np.linspace(1.7,6.7,41)
fit_curve = target_func(x_line, *popt)
fit_curve_u = target_func(x_line, popt[0]+perr[0],popt[1]+perr[1])
fit_curve_l = target_func(x_line, popt[0]-perr[0],popt[1]-perr[1])
fig, ax = plt.subplots()
# plt.loglog(x,f_x, 'b')
ax.errorbar(bins,nu, yerr=None, xerr=x_err, marker='.',linewidth = 0, elinewidth=2, color = 'k')
ax.loglog(x_line, fit_curve, '-')
ax.fill_between(x_line, fit_curve_l, fit_curve_u,alpha = 0.2)
# labels = ['high', 'low', 37337]
ax.set_xscale('log') # yes this is redundant
ax.set_xticks([2,3,4,5]) #this line ends up not working ):
ax.set_xlim([1.5,8.5])