I just used the cummeRbund, all steps according to the official manual.

> library(cummeRbund)
 >cuff<-readCufflinks(gtfFile = "cuffcmp.combined.gtf",genome="hg38")
 > cuff

But when I run:

> genes.scv<-fpkmSCVPlot(genes(cuff))

always output a wrong:

Scale for 'x' is already present. Adding another scale for 'x', which will replace the existing scale.

I can't find the parameter, where could I set the scale x, maybe someone could tell me.

Any help would be greatly appreciated. Thanks