I am using the R-scripting nodes for a while now and they are very useful to my research. But recently, every plot I want to make gives me an error. It is executed (light is green), but when I want to look at the view I get this error:
ERROR R Plot View instantiation failed: null
I added my logfile from my latest knime session to this post. I hope somebody can help me.
I also put the information on my blog:
Where are the images saved? Is there a way to change that?
And no, I also get this error when I try to do your boxplot with the iris data file.
The one from your template.
So I suppose there must be another error somewhere...
that's weird. Which R version do you use and is the Rserver locally installed or remote? I also have strange problems since a few days (and my colleague too). In my case the RPlot node fails if I use the local RServer. But I get a different error message:
ERROR R Snippet DataSpec generated by configure does not match spec after execution.
ERROR R Plot Execute failed: eval failed
I tried to debug this behaviour but I couldn't figure it out yet. The strange thing is that the plot works if I open an R-session ('Open in R' node) and copy paste the script...
We try to find out what's going wrong.
I use R-2.12.2 and my rServe is locally installed.
I just wanted to say that I got a workaround my initial error. In the tab output options it is possible to set a location for the image to save. (which I never had to to before, but it works)
For your problem, I remember seeing that error myself too, but I never bothered much with it. I'll see if I get it again what I did.
There are some issues with the older versions of Rserve.
make sure you have 0.6-2 or higher.