datatable.Frame.countna()

datatable.Frame.

countna

(

)

sourcetests

Report the number of NA values in each column of the frame.

Parameters

return

Frame

The frame will have one row and the same number/names of columns as in the current frame. All columns will have stype int64.

Examples

DT = dt.Frame(A=[1, 5, None], B=[math.nan]*3, C=[None, None, 'bah!']) DT.countna()

	A	B	C
	int64	int64	int64
0	1	3	2

1 row × 3 columns

DT.countna().to_tuples()[0] (1, 3, 2)

See Also

• .countna1() – similar to this method, but operates on a single-column frame only, and returns a number instead of a Frame.

• dt.count() – function for counting non-NA (“valid”) values in a column; can also be applied per-group.