Nothing
ntail <-
function(l,u)
{# samples a column vector of length=length(l)=length(u)
# from the standard multivariate normal distribution,
# truncated over the region [l,u], where l>0 and
# l and u are column vectors;
# uses acceptance-rejection from Rayleigh distribution;
# method due to Marsaglia (1964);
c=l^2/2;
n=length(l);
f=expm1(c-u^2/2)
x=c-log1p(runif(n)*f); # sample using Rayleigh
# keep list of rejected
I=which(runif(n)^2*x>c);
d=length(I)
while (d>0) { # while there are rejections
cy=c[I] # find the thresholds of rejected
y=cy-log1p(runif(d)*f[I])
idx=runif(d)^2*y<cy # accepted
x[I[idx]]=y[idx] # store the accepted
I=I[!idx] # remove accepted from list
d=length(I) # number of rejected
}
x=sqrt(2*x) # this Rayleigh transform can be delayed till the end
}
Any scripts or data that you put into this service are public.
Add the following code to your website.
For more information on customizing the embed code, read Embedding Snippets.