error when destranding during exporting bigwig

[alexg9010]

Error in `:=`(score, numCs/coverage) :
  Check that is.data.table(DT) == TRUE. Otherwise, := and `:=`(...) are defined for use in j, once only and in particular ways. See help(":=").
Calls: lapply ... <Anonymous> -> lapply -> FUN -> FUN -> [ -> [.data.frame -> :=
Execution halted

The problem is that the destranding function (

pigx_bsseq/scripts/export_tbx2bw.R

Lines 131 to 132 in 4b50572

	if(destrand) dt <- methylKit:::.CpG.dinuc.unifyOld(dt)
	dt[,score := numCs/coverage]

) converts the data.table to a data.frame and subsequent data.table column assignment via reference does not work.

easy solution would be to convert the function results into data.table again before proceeding

if(destrand) dt <- as.data.table(methylKit:::.CpG.dinuc.unifyOld(dt))