It looks like we've missed the unary minus operator when adding operators to Deedle frames! Aside from the unary minus, the rest actually works already.
So you can just change -log(...)
to -1.0 * log(...)
:
let minusLogOfOneLess (x:Frame<_, _>) = -1.0 * (log (1.0 - x))
frame [ "A" => series [1=>0.5; 2=>0.4]]
|> minusLogOfOneLess