from numpy import *
from scipy.special import sici
from matplotlib.pyplot import *
 
fig = figure(figsize=(4,3))
ax = fig.add_subplot(111)
x = linspace(0.001, 25, 100)
(y_sine,y_cosine) = sici(x);
ax.set_ylim(-6.5, 0.75)
ax.plot(x,y_cosine, linewidth=2, label=r"Ci$(x)=\gamma+\ln(x)+\int_0^x\frac{\cos(t)-1}{t}dt$")
ax.plot([0, 25], [0, 0], linestyle='--', color='g', label=r"asymptote");
ax.set_ylabel(r"Ci($x$)")
ax.set_xlabel(r"$x$")
ax.grid(True)
ax.minorticks_on()
fig.savefig("Cosine integral.svg",bbox_inches="tight",\
        pad_inches=.15)