dlaplace(x,mu,b) = 0.5/b * exp(-abs(x-mu)*1.0/b)
plaplace(x,mu,b) = 0.5*(1 + sgn(x-mu)*(1-exp(-abs(x-mu)*1.0/b)))
qlaplace(p,mu,b) = mu - b * sgn(p-0.5) * log(1 - 2*abs(p-0.5))
set samples 1001
set terminal postscript enhanced color solid lw 2 "Times-Roman" 20
set output
set xtics -10,2
set ytics 0,0.1
f(x,y,z) = dlaplace(x,y,z)
set yrange [0:0.55]
#f(x,y,z) = plaplace(x,y,z)
#set key bottom
plot [-10:10] \
f(x, 0,1) title "{/Symbol m} = 0, {/Times-Italic b} = 1", \
f(x, 0,2) title "{/Symbol m} = 0, {/Times-Italic b} = 2", \
f(x, 0,4) title "{/Symbol m} = 0, {/Times-Italic b} = 4", \
f(x,-5,4) title "{/Symbol m} = -5, {/Times-Italic b} = 4"
本作品为自由软件,您可以依据自由软件基金会发行的GNU通用公共许可证第2版或任意后续版本的条款,传播和/或修改本作品。本作品发表时预期有用,但对此无任何保证,亦无隐含的可以销售或适合特定目的的保证。详情请见GNU通用公共许可证第2版和第3版。http://www.gnu.org/licenses/gpl.htmlGPLGNU General Public Licensetruetrue