[R] date format in xyplot

[Christine Lee]

To whom it may concern,

I have tried to plot some numbers against time with the time on the X-axis shown as "Jan", "Feb", etc.

I used the following commands:
Raw<-structure(list(Date = structure(c(6L, 7L, 2L, 4L, 12L, 9L, 7L, 
2L, 4L, 12L), .Label = c("1/10", "1/11", "11/11", "12/11", "13/10", 
"19/9", "2/10", "2/11", "20/9", "26/11", "29/10", "29/11", "30/11", 
"31/10", "4/10", "6/10"), class = "factor"), Year = c(2002L, 
2002L, 2002L, 2002L, 2002L, 2002L, 2002L, 2002L, 2002L, 2002L
), Station = structure(c(1L, 1L, 1L, 1L, 1L, 2L, 2L, 2L, 2L, 
2L), .Label = c("E", "F", "H", "I"), class = "factor"), Abun = c(3.42, 
1.33, 3.67, 3.67, 3.92, 2.17, 2.5, 1.67, 6.33, 0.67), Date1 = structure(c(16697, 
16710, 16740, 16751, 16768, 16698, 16710, 16740, 16751, 16768
), class = "Date")), .Names = c("Date", "Year", "Station", "Abun", 
"Date1"), row.names = c(NA, 10L), class = "data.frame")

Raw$Date1<-as.Date(Raw$Date,"%d/%m")
xyplot(Abun~Date1|as.factor(Year),Raw,type="p",xlab=list("Month",cex=1.5),ylab=list("Abundance",cex=1.5),cex=2,pch=c(16,16,21),col=c("Black","Grey","Black"),strip=strip.custom(bg='white'),format="%B-%d")

The date format shown on X-axis was just "10-1", "10-15"

I should be grateful if any one could help indicating what has gone wrong?

Regards,
Christine