This would probably also be interesting to some: On 2007-October-01 , at 00:48 , hadley wickham wrote: >> That's great! >> In fact I think I found exactly what I was looking for. I can just >> do: >> p = ggplot() + coord_equal() >> p$aspect.ratio = 1 >> to set up the plot, and then add the layers and have ggplot take care >> of resizing and laying out everything automagically: >> p = p + geom_path(data=coast, mapping=aes(x=lon, y=lat)) >> p = p + geom_point(data=coords, mapping=aes(x=lon, y=lat)) >> p = p + geom_text(data=coords, mapping=aes(x=lon, y=lat, >> label=station)) >> etc... >> Oh, I love ggplot ;) ! > > Or even less verbosely: > > p = ggplot(mapping = aes(x=lon, y= lat) + coord_equal() > p = p + geom_path(data=coast) > p = p + geom_point(data=coords) > p = p + geom_text(data=coords, aes(label = station)) > >>> The data is completely independent of the plot specification. >>> This is >>> very different from the other plotting models in R, so it may take a >>> while to get your head around it. >> >> Yes, indeed. That's a completely new way of thinking (especially >> given my MATLAB, Scilab background) but how powerful! I found the >> whole "data mapping" concept very elegant but did not grasp all the >> flexibility behind it. I wonder how mainstream it can get since so >> many people are used to an other graphics paradigm. > > It's definitely a big change, but I hope that people will see the > potential benefits and invest some time learning it. I definitely > have a lot to improve on the documentation though! > >> Anyway, I just need to define a new geom_arrow now, to plot wind >> velocities arrows at several locations, and I'll be a happy man. Is >> there a specific reason why '...' arguments are not passed to grid >> functions or is it just to keep the complexity under control? I am >> thinking in particular that: >> p = ggplot(coords) + geom_segment(mapping=aes(x=lon, >> y=lat, xend=lon >> +0.03 ,yend=lat+-0.02), arrow=arrow(length=unit(0.1,"inches"))) >> would do exactly what I want provided that the 'arrow' argument is >> passed on to segmentsGrob which is used in geom_segment. > > In general, ... doesn't get passed on to the underlying grid function > because there isn't a one-to-one mapping from geoms to grobs (take > geom_boxplot for example). However, funnily enough, I have just added > the arrows argument to geom_segment for my sister, so if you let me > know what platform you're on, I can send you an updated version.
JiHO --- http://jo.irisson.free.fr/ ______________________________________________ R-help@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.
