R View (Table) not producing legend

I’m trying to make a volcano plot using the ‘R View (Table)’ node in KNIME, and I am plotting the data from a few different sample types together. My input table hence has columns that specify shape, color, and size for each row to go with their sample type. The plot looks really good, except I cannot get a legend to render on it. I’m using ggplot2 to draw the plot in R.
I’ve tried a few different approaches and I can’t seem to get the node to draw the legend at all. I’ve also added another column “label” to my table to designate which row is which type of sample but that hasn’t been useful either. With the columns I’ve added my table is 11,445 rows x 6 columns.
Can anyone offer a hint on how to get the legend to render? I’ve been looking into ggplot2 syntax but that hasn’t led me anywhere yet.

Could you provide us with an example where there is no legend so maybe someone could have a look how to fix it.


could you please provide us with your R code? I’m not able to reproduce your problem.