LopComparator (Apache SystemDS 3.0.0 API)

java.lang.Object
- org.apache.sysds.lops.compile.LopComparator<N>

Type Parameters:

N - class extending Lop

All Implemented Interfaces:

Comparator<N>
```
public class LopComparator<N extends Lop>
extends Object
implements Comparator<N>
```
Comparator class used in sorting the LopDAG in topological order. Refer to doTopologicalSort_strict_order() in dml/lops/compile/Dag.java Topological sort guarantees the following: 1) All lops with level i appear before any lop with level greater than i (source nodes are at level 0) 2) Within a given level, nodes are ordered by their ID i.e., by the other in which they are created compare() method is designed to respect the above two requirements.

- Constructor Summary
  
  Constructors
  Constructor Description
  
  LopComparator()
- Method Summary
  
  All Methods Instance Methods Concrete Methods
  Modifier and Type Method Description
  
  int compare(N o1, N o2)
  - Methods inherited from class java.lang.Object
    equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
  - Methods inherited from interface java.util.Comparator
    equals, reversed, thenComparing, thenComparing, thenComparing, thenComparingDouble, thenComparingInt, thenComparingLong

- Constructor Detail
  - LopComparator
```
public LopComparator()
```
- Method Detail
  - compare
```
public int compare(N o1,
                   N o2)
```
    Specified by:
    
    compare in interface Comparator<N extends Lop>