python - How to fillna() with value 0 after calling resample?

Question

Either I don't understand the documentation or it is outdated.

If I run

user[["DOC_ACC_DT", "USER_SIGNON_ID"]].groupby("DOC_ACC_DT").agg(["count"]).resample("1D").fillna(value=0, method="ffill")

It get

TypeError: fillna() got an unexpected keyword argument 'value'

If I just run

.fillna(0)

I get

ValueError: Invalid fill method. Expecting pad (ffill), backfill (bfill) or nearest. Got 0

If I then set

.fillna(0, method="ffill") 

I get

TypeError: fillna() got multiple values for keyword argument 'method'

so the only thing that works is

.fillna("ffill")

but of course that makes just a forward fill. However, I want to replace NaN with zeros. What am I doing wrong here?

Answer 1

Well, I don't get why the code above is not working and I'm going to wait for somebody to give a better answer than this but I just found

.replace(np.nan, 0)

does what I would have expected from .fillna(0).