wilcox_R: What the package does (short line)

powest <-
function(x=NA,y=NA,delta=0,se=NA,wv1=NA,wv2=NA,n1=NA,n2=NA){
#
# wv1 = Winsorized variance for group 1
# wv2 = Winsorized variance for group 2
#
# Only 20% trimming is allowed.
#
tr<-.2
if(is.na(se)){
if(is.na(wv1)){
h1 <- length(x) - 2 * floor(tr * length(x))
h2 <- length(y) - 2 * floor(tr * length(y))
q1 <- ((length(x) - 1) * winvar(x, tr))/(h1 * (h1 - 1))
q2 <- ((length(y) - 1) * winvar(y, tr))/(h2 * (h2 - 1))
}
if(!is.na(wv1)){
if(is.na(n1))stop("Need to specify sample size for group 1")
if(is.na(n2))stop("Need to specify sample size for group 2")
h1<-n1-2*floor(tr*n1)
h2<-n2-2*floor(tr*n2)
q1<-(n1-1)*wv1/(h1*(h1-1))
q2<-(n2-1)*wv2/(h2*(h2-1))
}
se<-sqrt(q1+q2)
}
ygam<-sqrt(2*.01155)*c(0:35)/8
pow<-c(500.0,540.0,607.0, 706.0, 804.0,981.0,1176.0,1402.0,1681.0, 2008.0,
   2353.0, 2769.0, 3191.0, 3646.0, 4124.0, 4617.0, 5101.0, 5630.0,
   6117.0, 6602.0, 7058.0, 7459.0, 7812.0, 8150.0, 8479.0, 8743.0,
   8984.0, 9168.0, 9332.0, 9490.0, 9607.0, 9700.0, 9782.0, 9839.0,
   9868.0)/10000
flag<-(delta==0 && se==0)
if(flag)powest<-.05
else{
chk<-floor(8*delta/se)+1
chk1<-chk+1
gval<-delta/se
d1<-(gval-(chk-1)/8)*8
if(chk > length(pow))powest<-1
if(chk == length(pow))pow[chk1]<-1
if(chk <= length(pow))
powest<-pow[chk]+d1*(pow[chk1]-pow[chk])
}
powest
}