This provides something analogous to contour()
, but with the
ability to flip x and y.
Setting revy=TRUE
can be helpful if the y
data represent
pressure or depth below the surface.
values for x grid.
values for y grid.
matrix for values to be contoured. The first dimension of z
must equal the number of items in x
, etc.
set to TRUE
to reverse the order in which the labels on
the x axis are drawn
set to TRUE
to reverse the order in which the labels on
the y axis are drawn
logical value indicating whether the contours should be added to a pre-existing plot.
time format; if not supplied, a reasonable choice will be
made by oce.axis.POSIXct()
, which draws time axes.
logical, only used if the x
axis is a time. If
TRUE
, then an indication of the time range of the data (not the axis)
is indicated at the top-left margin of the graph. This is useful because
the labels on time axes only indicate hours if the range is less than a day,
etc.
a flag that turns on debugging; set to 1 to information about the processing.
optional arguments passed to plotting functions.
library(oce)
data(topoWorld)
# coastline now, and in last glacial maximum
lon <- topoWorld[["longitude"]]
lat <- topoWorld[["latitude"]]
z <- topoWorld[["z"]]
oce.contour(lon, lat, z, levels = 0, drawlabels = FALSE)
oce.contour(lon, lat, z, levels = -130, drawlabels = FALSE, col = "blue", add = TRUE)