contour plot with date-time strings as x values

Question

I am trying to produce a color contour plot showing time along the x axis, depth along the y and temperature as the z values. Time is given as:

"2011-01-01 00:01"

i.e. "%Y-%m-%d %H:%M"

Is there a method for producing the color contour plot from these, and using

filled.contour(Time,Depth,temp)

example:

time <- c("2011-01-01 01:00", "2011-01-01 02:00", "2011-01-01 03:00",
    "2011-01-01 04:00")
depth <- seq(1,10,by = 1)
seq1 <-  seq(1:40)
temp <- matrix(seq1, 10)

Every column of temp represents a different time and every row represents a different depth.

Answer 1

This works for me:

time2 <- as.POSIXct(time)

Result:

> time2
## [1] "2011-01-01 01:00:00 EST" "2011-01-01 02:00:00 EST"
## [3] "2011-01-01 03:00:00 EST" "2011-01-01 04:00:00 EST"

Now plot it:

filled.contour(time2,depth,t(temp))