I have a math question. I am doing differential expression test. My expression data is already log2'd. I would like to perform t-test between control-case for all genes using `t.test` function in r. I wonder how to correctly calculate fold change?
for example, if `t.test` result is saved as `res`. It also calculates means of two groups (case, control). Should I use `res$estimate - res$estimate`?
Thank you in advance.