filled maps

-----Mensaje original-----
De: Janus Larsen [mailto:janus at ices.dk]
Enviado el: martes, 03 de febrero de 2004 11:36
Para: antonio rodriguez
Asunto: RE: [R] filled maps


Hi Antonio,

Thanks for your prompt answer - but I can't see how that will solve my
problem (which is overlaying contour plots with filled coastlines from
the mapdata package).
As far as I can see, what you show is how to add contour lines to a
filled contour plot.. Or am I missing something?

Cheers,
Janus

-----Original Message-----
From: antonio rodriguez [mailto:arv at ono.com] 
Sent: 03 February 2004 11:28
To: Janus Larsen; R-help at stat.math.ethz.ch
Subject: RE: [R] filled maps


Hi,

Some time ago, Roger Peng posted this solution, which I found very
useful:

junk.mat <- matrix(rnorm(1600), 16, 100)
contour.mat <- ifelse(junk.mat < 2, 0, junk.mat)
filled.contour(junk.mat, color = terrain.colors, 
               plot.axes = contour(contour.mat, levels = 1, 
                                   drawlabels = FALSE, axes = FALSE, 
                                   frame.plot = FFALSE, add = TRUE))

The 'plot.axes' argument to filled.contour() gives you access to the
coordinate system in the actual plotting area.  However, you will notice
that the axes are missing.  You need to add them explicitly, as in:

filled.contour(junk.mat, color = terrain.colors, 
               plot.axes = { contour(contour.mat, levels = 1, 
                                     drawlabels = FALSE, axes = FALSE, 
                                     frame.plot = FFALSE, add = TRUE);
			     axis(1); axis(2) } )


Cheers,

Antonio

-----Mensaje original-----
De: r-help-bounces+arv=ono.com at stat.math.ethz.ch
[mailto:r-help-bounces+arv=ono.com at stat.math.ethz.ch]En nombre de 
Janus Larsen Enviado el: martes, 03 de febrero de 2004 9:36
Para: R-help at stat.math.ethz.ch
Asunto: [R] filled maps


Hi R-Help,

I would like to make filled contour maps of ocean data overlaid by 
costlines from the map package. I can draw the filled contours and the

coastlines om the same plot, but the filled contour also covers part 
of the land. To get rid of that I tried to draw a filled coastline map

on top of the filled contour, but the filled map only draws the closed

contours - so most of the land is missing.
Example:
map("worldHires",xlim=c(0,15),ylim=c(50,60)) #Draw relevant region
(North Sea and Denmark waters)
map("worldHires",xlim=c(0,15),ylim=c(50,60),fill=TRUE) # This only

draws

Denmark and Holland (Sweden, uk, Germany etc. disappears because they
are not closed polygons).

Any hint on how to fix this problem or a different approach is most 
welcome. Janus