PageRank

class hana_ml.algorithms.pal.pagerank.PageRank(damping=None, max_iter=None, tol=None, thread_ratio=None)

A page rank model.

Parameters
dampingfloat, optional

The damping factor d.

Defaults to 0.85.

max_iterint, optional

The maximum number of iterations of power method.

The value 0 means no maximum number of iterations is set and the calculation stops when the result converges.

Defaults to 0.

tolfloat, optional

Specifies the stop condition.

When the mean improvement value of ranks is less than this value, the program stops calculation.

Defaults to 1e-6.

thread_ratiofloat, optional

Specifies the ratio of total number of threads that can be used by this function.

The value range is from 0 to 1, where 0 means only using 1 thread, and 1 means using at most all the currently available threads.

Values outside the range will be ignored and this function heuristically determines the number of threads to use.

Defaults to 0.

Examples

Input dataframe df for training:

>>> df.collect()
   FROM_NODE    TO_NODE
0   Node1       Node2
1   Node1       Node3
2   Node1       Node4
3   Node2       Node3
4   Node2       Node4
5   Node3       Node1
6   Node4       Node1
7   Node4       Node3

Create a PageRank instance:

>>> pr = PageRank()

Call run() on given data sequence:

>>> result = pr.run(data=df)
>>> result.collect()
   NODE     RANK
0   NODE1   0.368152
1   NODE2   0.141808
2   NODE3   0.287962
3   NODE4   0.202078
Attributes
None

Methods

run(data)

This method reads link information and calculates rank for each node.
run(data)

This method reads link information and calculates rank for each node.

Parameters
dataDataFrame

Data for predicting the class labels.

Returns
DataFrame

Calculated rank values and corresponding node names, structured as follows:

  • NODE: node names.

  • RANK: the PageRank of the corresponding node.

property fit_hdbprocedure

Returns the generated hdbprocedure for fit.

property predict_hdbprocedure

Returns the generated hdbprocedure for predict.

Inherited Methods from PALBase

Besides those methods mentioned above, the PageRank class also inherits methods from PALBase class, please refer to PAL Base for more details.