EdgeFrame top_k

---

top_k(self, column_name, k, weights_column=None)

Most or least frequent column values.

Parameters:

column_name : unicode

The column whose top (or bottom) K distinct values are to be calculated.

k : int32

Number of entries to return (If k is negative, return bottom k).

weights_column : unicode (default=None)

The column that provides weights (frequencies) for the topK calculation. Must contain numerical data. Default is 1 for all items.

Returns:

: <bound method AtkEntityType.__name__ of <trustedanalytics.rest.jsonschema.AtkEntityType object at 0x7f9e686f3fd0>>

An object with access to the frame of data.

Calculate the top (or bottom) K distinct values by count of a column. The column can be weighted. All data elements of weight <= 0 are excluded from the calculation, as are all data elements whose weight is NaN or infinite. If there are no data elements of finite weight > 0, then topK is empty.

Examples

For this example, we calculate the top 5 movie genres in a data frame:

>>> top5 = frame.top_k('genre', 5)
>>> top5.inspect()

  genre:str   count:float64
/---------------------------/
  Drama        738278
  Comedy       671398
  Short        455728
  Documentary  323150
  Talk-Show    265180

This example calculates the top 3 movies weighted by rating:

>>> top3 = frame.top_k('genre', 3, weights_column='rating')
>>> top3.inspect()

  movie:str      count:float64
/------------------------------/
  The Godfather         7689.0
  Shawshank Redemption  6358.0
  The Dark Knight       5426.0

This example calculates the bottom 3 movie genres in a data frame:

>>> bottom3 = frame.top_k('genre', -3)
>>> bottom3.inspect()

  genre:str   count:float64
/---------------------------/
  Musical       26
  War           47
  Film-Noir    595