Bug in spawn when using regular =F, example code:
myseq <- seq(0, 24, length=1001)
myseq <- myseq[-1]
plot(seq(1,24,length=1000), spawn(myseq[c(700:1000, 1:699)], mu=19, sig=4, regular=T), type="l")
lines(seq(1,24,length=1000), spawn(myseq[c(700:1000, 1:699)], mu=19, sig=4, regular=F), col="red")