plot.tdr: plot for TDR data
In SESman/rbl: Biologging tools for diving predators in R

When depth in input set in as Y and reverse axe. Use third column as a color variable.

1 2	## S3 method for class 'tdr' plot(x, type = "l", ...)

`x`	TDR data
`type`	as in `plot`
`...`	as in `plot`

data(exses)
tdrply(plot, c("time", "depth", "is_pca"), no = 65, obj = exses)

exses$tdr$no_btt <- tdrexpand(exses$stat$no_dive, ty = "_", obj = exses)
exses$tdr$is_btt <- !is.na(exses$tdr$no_btt)
tdrply(plot, c("time", "depth", "is_btt"), no = 65, obj = exses)
tdrply(plot, c("depth", "temp", "is_btt"), no = 65, obj = exses)