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Summary
Description 
English: Some lognormal distributions.

Date 
27 February 2011 
Source 
Own work 
Author 
Derivative by Mikael Häggström from the original, File:Lognormal distribution PDF.png by User:Par 
✓ The source code of this SVG is valid.
Source Code 
from numpy import *
from matplotlib.pyplot import *
from mpl_toolkits.axes_grid.axislines import SubplotZero
pdf = lambda s,m,x: exp((log(x)m)**2 / (2.*s**2)) / ( x*sqrt(2.*pi*s**2) )
fig = figure(figsize=(7,7))
ax = SubplotZero(fig,111)
fig.add_subplot(ax)
for direction in ["xzero","yzero"]:
ax.axis[direction].set_visible(True)
ax.axis[direction].set_axisline_style(">")
for direction in ["top","bottom","left","right"]:
ax.axis[direction].set_visible(False)
ax.axis["yzero"].set_axis_direction("left")
ax.grid(False)
ax.minorticks_on()
x = linspace(.001,3,150)
ax.plot(x,pdf(1.,0.,x))
ax.text(.1,.7,r'$\mu=0$, $\sigma=1$',colour='b')
ax.plot(x,pdf(.5,0.,x),'g')
ax.text(.15,.9,r'$\mu=0$, $\sigma=0.5$',colour='g')
ax.plot(x,pdf(.25,0.,x),'r')
ax.text(.5,1.7,r'$\mu=0$, $\sigma=0.25$',colour='r')
ax.set_ylim(0,2.1)
ax.set_xlim(0,3)
ax.axis["xzero"].label.set_text(r'$x$')
ax.axis["yzero"].label.set_text(r'$f_x(x;\mu,\sigma)=\frac{1}{x\sigma\sqrt{2\pi}}e^{\frac{\left(\ln x\mu\right)^2}{2\sigma^2}}$')
fig.savefig("Test.svg",bbox_inches="tight",pad_inches=.15)

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