Hello. I am new on R and I am sampling the DEP example dataset along with its codes provided (https://www.bioconductor.org/packages/release/bioc/vignettes/DEP/inst/doc/DEP.html#overview-of-the-analysis). However, I keep getting this error when I run this code (on section 4.6):

plot_frequency(data_se)

I get this error:

Error in plot_frequency(data_se) : could not find function "plot_frequency"

Any assistance would be greatly appreciated.

Thank you.