gatk-3.8/public/R/titvFPEst.R

139 lines
3.7 KiB
R
Executable File

titvFPEst <- function(titvExpected, titvObserved) { max(min(1 - (titvObserved - 0.5) / (titvExpected - 0.5), 1), 0.001) }
titvFPEstV <- function(titvExpected, titvs) {
sapply(titvs, function(x) titvFPEst(titvExpected, x))
}
calcHet <- function(nknown, knownTiTv, nnovel, novelTiTv, callable) {
TP <- nknown + (1-titvFPEst(knownTiTv, novelTiTv)) * nnovel
2 * TP / 3 / callable
}
marginalTiTv <- function( nx, titvx, ny, titvy ) {
tvx = nx / (titvx + 1)
tix = nx - tvx
tvy = ny / (titvy + 1)
tiy = ny - tvy
tiz = tix - tiy
tvz = tvx - tvy
return(tiz / tvz)
}
marginaldbSNPRate <- function( nx, dbx, ny, dby ) {
knownx = nx * dbx / 100
novelx = nx - knownx
knowny = ny * dby / 100
novely = ny - knowny
knownz = knownx - knowny
novelz = novelx - novely
return(knownz / ( knownz + novelz ) * 100)
}
numExpectedCalls <- function(L, theta, calledFractionOfRegion, nIndividuals, dbSNPRate) {
nCalls <- L * theta * calledFractionOfRegion * sum(1 / seq(1, 2 * nIndividuals))
return(list(nCalls = nCalls, nKnown = dbSNPRate * nCalls, nNovel = (1-dbSNPRate) * nCalls))
}
normalize <- function(x) {
x / sum(x)
}
normcumsum <- function(x) {
cumsum(normalize(x))
}
cumhist <- function(d, ...) {
plot(d[order(d)], type="b", col="orange", lwd=2, ...)
}
revcumsum <- function(x) {
return(rev(cumsum(rev(x))))
}
phred <- function(x) {
log10(max(x,10^(-9.9)))*-10
}
pOfB <- function(b, B, Q) {
#print(paste(b, B, Q))
p = 1 - 10^(-Q/10)
if ( b == B )
return(p)
else
return(1 - p)
}
pOfG <- function(bs, qs, G) {
a1 = G[1]
a2 = G[2]
log10p = 0
for ( i in 1:length(bs) ) {
b = bs[i]
q = qs[i]
p1 = pOfB(b, a1, q) / 2 + pOfB(b, a2, q) / 2
log10p = log10p + log10(p1)
}
return(log10p)
}
pOfGs <- function(nAs, nBs, Q) {
bs = c(rep("a", nAs), rep("t", nBs))
qs = rep(Q, nAs + nBs)
G1 = c("a", "a")
G2 = c("a", "t")
G3 = c("t", "t")
log10p1 = pOfG(bs, qs, G1)
log10p2 = pOfG(bs, qs, G2)
log10p3 = pOfG(bs, qs, G3)
Qsample = phred(1 - 10^log10p2 / sum(10^(c(log10p1, log10p2, log10p3))))
return(list(p1=log10p1, p2=log10p2, p3=log10p3, Qsample=Qsample))
}
QsampleExpected <- function(depth, Q) {
weightedAvg = 0
for ( d in 1:(depth*3) ) {
Qsample = 0
pOfD = dpois(d, depth)
for ( nBs in 0:d ) {
pOfnB = dbinom(nBs, d, 0.5)
nAs = d - nBs
Qsample = pOfGs(nAs, nBs, Q)$Qsample
#Qsample = 1
weightedAvg = weightedAvg + Qsample * pOfD * pOfnB
print(as.data.frame(list(d=d, nBs = nBs, pOfD=pOfD, pOfnB = pOfnB, Qsample=Qsample, weightedAvg = weightedAvg)))
}
}
return(weightedAvg)
}
plotQsamples <- function(depths, Qs, Qmax) {
cols = rainbow(length(Qs))
plot(depths, rep(Qmax, length(depths)), type="n", ylim=c(0,Qmax), xlab="Average sequencing coverage", ylab="Qsample", main = "Expected Qsample values, including depth and allele sampling")
for ( i in 1:length(Qs) ) {
Q = Qs[i]
y = as.numeric(lapply(depths, function(x) QsampleExpected(x, Q)))
points(depths, y, col=cols[i], type="b")
}
legend("topleft", paste("Q", Qs), fill=cols)
}
pCallHetGivenDepth <- function(depth, nallelesToCall) {
depths = 0:(2*depth)
pNoAllelesToCall = apply(as.matrix(depths),1,function(d) sum(dbinom(0:nallelesToCall,d,0.5)))
dpois(depths,depth)*(1-pNoAllelesToCall)
}
pCallHets <- function(depth, nallelesToCall) {
sum(pCallHetGivenDepth(depth,nallelesToCall))
}
pCallHetMultiSample <- function(depth, nallelesToCall, nsamples) {
1-(1-pCallHets(depth,nallelesToCall))^nsamples
}