R devel - Jul 2003 - wrong axis scale when plotting on a filled.contour plot (PR#3596)

Full_Name: Marco Gruteser
Version: 1.7.1
OS: Win XP
Submission from: (NULL) (129.34.20.16)


Let's generate a dummy filled.contour plot
> x <- 1:10
> y <- 1:10
> z <- array(rep(0, times=100),dim=c(10,10))
> filled.contour(x,y,z)
And try to add some points to it, e.g.
> points(8,2)
> points(6,2)
The points show up misaligned with the axis 
somewhere at 9.9,2 and 7.5,2

It appears that the "z value legend" on the right
may have distorted the axis.

gruteser@colorado.edu wrote:
> Full_Name: Marco Gruteser
> Version: 1.7.1
> OS: Win XP
> Submission from: (NULL) (129.34.20.16)
> 
> 
> Let's generate a dummy filled.contour plot
> 
> 
>>x <- 1:10
>>y <- 1:10
>>z <- array(rep(0, times=100),dim=c(10,10))
>>filled.contour(x,y,z)
> 
> 
> And try to add some points to it, e.g.
> 
> 
>>points(8,2)
>>points(6,2)
> 
> 
> The points show up misaligned with the axis 
> somewhere at 9.9,2 and 7.5,2
> 
> It appears that the "z value legend" on the right
> may have distorted the axis.
> 
> ______________________________________________
> R-devel@stat.math.ethz.ch mailing list
> https://www.stat.math.ethz.ch/mailman/listinfo/r-devel
That's not a bug! It's documented, as well as it's solution. See 
?filled.contour, Section "Note":

"The ouput produced by filled.contour is actually a combination of two 
plots; one is the filled contour and one is the legend. Two separate 
coordinate systems are set up for these two plots, but they are only 
used internally - once the function has returned these coordinate 
systems are lost. If you want to annotate the main contour plot, for 
example to add points, you can specify graphics commands in the 
plot.axes argument. An example is given below."

Please check those examples as well.

Uwe Ligges