Filtering all rows with NaT in a column in Dataframe python

Question

I have a df like this:

    a b           c
    1 NaT         w
    2 2014-02-01  g
    3 NaT         x   

    df=df[df.b==\'2014-02-01\']

Answer 1

Using your example dataframe:

df = pd.DataFrame({"a":[1,2,3], 
                   "b":[pd.NaT, pd.to_datetime("2014-02-01"), pd.NaT], 
                   "c":["w", "g", "x"]})

Until v0.17 this didn't use to work:

df.query('b != b') 

and you had to do:

df.query('b == "NaT"') # yes, surprisingly, this works!

Since v0.17 though, both methods work, although I would only recommend the first one.