Add a Grid to an Existing Oce Plot

oce.grid(xat, yat, col = "lightgray", lty = "dotted", lwd = par("lwd"))



either a list of x values at which to draw the grid, or the return value from an oce plotting function


a list of y values at which to plot the grid (ignored if gx was a return value from an oce plotting function)


color of grid lines (see par())


type for grid lines (see par())


width for grid lines (see par())


For plots not created by oce functions, or for missing xat and yat, this is the same as a call to grid() with missing nx and ny. However, if xat is the return value from certain oce functions, a more sophisticated grid is constructed. The problem with grid() is that it cannot handle axes with non-uniform grids, e.g. those with time axes that span months of differing lengths.

As of early February 2015, oce.grid handles xat produced as the return value from the following functions: imagep() and oce.plot.ts(), plot,adp-method(), plot,echosounder-method(), and plotTS(). It makes no sense to try to use oce.grid for multipanel oce plots, e.g. the default plot from plot,adp-method().


library(oce) i <- imagep(volcano)
oce.grid(i, lwd=2)
data(sealevel) i <- oce.plot.ts(sealevel[["time"]], sealevel[["elevation"]])
oce.grid(i, col='red')
data(ctd) i <- plotTS(ctd)
oce.grid(i, col='red')
data(adp) i <- plot(adp, which=1)
oce.grid(i, col='gray', lty=1)
data(echosounder) i <- plot(echosounder)
oce.grid(i, col='pink', lty=1)