testnhoods with interaction effect

[michaelhojungyoon]

Hello, I've been trying to run testNhoods() with an interaction term ~condition*drug, but I get the following error:

Error in makeContrasts(contrasts = model.contrasts, levels = x.model) : The levels must by syntactically valid names in R, see help(make.names). Non-valid names: conditionDE:drugBud

I'm assuming the issue is the colon symbol that is generated from the model matrix, but I'm not quite sure how to manipulate the model.contrasts argument to change the interaction term "conditionDE:drugBud" to an appropriate syntax.

[MikeDMorgan]

The column names of your model matrix are character strings therefore you can manipulate them any way you would any other string.