R help - Feb 1999 - Eyeball problem ...

Just a point about plotting and abline with a dotted grid.  Try this for
size: 

eh<-function (mx, my, line='dotted') 
{
    x <- c(0, mx)
    y <- c(0, my)
    plot(x, y, "l")
    abline(v = seq(0, mx, 10), h = seq(0, my, 10), lty = line)
}

eh(100,100)
eh(100,1000)
eh(100,5000)
eh(100,10000)

When there are enough horizontal lines, the dotted characteristic makes it
look vertical!  Had me puzzled for a bit.  Try it with line='' as well. 
Actually it is worse with (eg) eh(10000,100) but I was considering your
collective health.

Is there any simple way of returning the axis label values that can be
passed to abline, or enforcing abline to put the grid against these?  This
is what I was actually trying to do when my eyeballs fell out.

\John

-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-
r-help mailing list -- Read http://www.ci.tuwien.ac.at/~hornik/R/R-FAQ.html
Send "info", "help", or "[un]subscribe"
(in the "body", not the subject !)  To: r-help-request at
stat.math.ethz.ch
_._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._

For what it's worth, *if* you have the luxury of a color medium (such as
a screen) this looks much better (in my opinion at least) if you make the
grid lines solid and grey, rather than dotted and black, which eliminates
all the funky dot-pattern-aliasing stuff (a tip from Edward Tufte)

  Ben




-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-
r-help mailing list -- Read http://www.ci.tuwien.ac.at/~hornik/R/R-FAQ.html
Send "info", "help", or "[un]subscribe"
(in the "body", not the subject !)  To: r-help-request at
stat.math.ethz.ch
_._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._