ZDD

java.lang.Object
- jdd.bdd.NodeTable
- - jdd.zdd.ZDD

Direct Known Subclasses:

ZDD2, ZDDGraph
```
public class ZDD
extends NodeTable
```
Base implementation for Zero-Supressed Binary Decision Diagrams (Z-BDDs). Z-BDDs are a special type of BDDs that are more suited for sparse sets. For example, if you are working with a set that is most of the time empty, you might want to use Z-BDDs instead of BDDs.
The base implementation will give you the core Z-BDD operation such as change, diff and union. To get more operators, see the sub-classes.

See Also:

BDD, ZDD2, ZDDCSP

Field Summary

Fields
Modifier and Type Field and Description

protected NodeName nodeNames

protected int num_vars
- Fields inherited from class jdd.bdd.NodeTable
  dead_nodes, ht_chain, mark_stack, NODE_MARK, NODE_UNMARK, nodesminfree, stat_gc_count, stat_gc_freed, stat_gc_time, stat_grow_time, stat_lookup_count, stat_notify_time, stat_nt_grow, table_size, work_stack, work_stack_tos

Fields
Modifier and Type	Field and Description
`protected NodeName`	`nodeNames`
`protected int`	`num_vars`

Constructor Summary

Constructors
Constructor and Description

ZDD(int nodesize)
create a Z-BDD manager

ZDD(int nodesize, int cachesize)
create a Z-BDD manager

Constructors
Constructor and Description
`ZDD(int nodesize)` create a Z-BDD manager
`ZDD(int nodesize, int cachesize)` create a Z-BDD manager

Method Summary

All Methods Static Methods Instance Methods Concrete Methods
Modifier and Type	Method and Description
`Collection`	`addDebugger(BDDDebuger d)` for debugging: install a debugger.
`int`	`base()` returns {{}}
`int`	`change(int zdd, int var)`
`void`	`cleanup()` cleanup this ZDD, to release its memory and help GC
`int`	`count(int zdd)`
`int`	`createVar()` create a new ZDD variable
`int`	`cube(boolean[] v)` cube of a selection of variables
`int`	`cube(int v)` cube of a single variable v
`int`	`cube(String s)` cube of a selection of variables, represented as a string, e.g.
`int`	`cubes_intersect(String s)` Intersection of cubes.
`int`	`cubes_union(String s)` Union of cubes, each represented by a string token.
`int`	`diff(int p, int q)`
`int`	`diffTo(int set, int add)` helper function to compute set' = set - add, derefs the old set!
`int`	`empty()` returns {}
`boolean`	`emptyIn(int X)` returns true if base {{}} is in X
`int`	`follow_high(int zdd)` returns the terminal value along the all-high path
`int`	`follow_low(int zdd)` returns the terminal value along the all-low path
`long`	`getMemoryUsage()` return the amount of internally allocated memory in bytes
`static void`	`internal_test()` testbench.
`int`	`intersect(int p, int q)`
`protected int`	`mk(int i, int l, int h)` Zero-supressed MK operator
`int`	`nodeCount(int zdd)` compute the number of nodes in the tree (this function is currently somewhat slow)
`protected void`	`post_removal_callbak()` this function is called when something in the node table is changed (GC or grow).
`void`	`print(int zdd)`
`void`	`printCubes(int bdd)`
`void`	`printDot(String fil, int bdd)`
`void`	`printSet(int bdd)`
`boolean[]`	`satOne(int zdd, boolean[] vec)` Returns a satisfying boolean assignment, null if none XXX: this code is still untested!
`void`	`setNodeNames(NodeName nn)`
`void`	`showStats()` show ZDD statistics
`int`	`single(int var)` create a tree of a variable.
`int`	`subset0(int zdd, int var)` var is a variable, NOT a tree
`int`	`subset1(int zdd, int var)` var is a variable, NOT a tree
`int`	`subsets(boolean[] v)`
`int`	`union(int p, int q)`
`int`	`unionTo(int set, int add)` helper function to compute set' = set UNION add, derefs the old set!
`int`	`universe()`

Methods inherited from class jdd.bdd.NodeTable
add, check_all_nodes, check_node, countRootNodes, deref, enableStackMarking, gc, getHigh, getLow, getRef, getVar, getVarUnmasked, grow, invalidate, isNodeMarked, isValid, mark_node, mark_tree, match_table, ref, saturate, setAll, setAll, show_table_all, show_table, show_tuple, signal_removed, tree_depth_changed, unmark_node, unmark_tree, update_grow_parameters

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

- Field Detail
  - num_vars
```
protected int num_vars
```
  - nodeNames
```
protected NodeName nodeNames
```
- Constructor Detail
  - ZDD
```
public ZDD(int nodesize)
```
    create a Z-BDD manager
    
    Parameters:
    
    nodesize - is the number of nodes initially allocated in the node-table
  - ZDD
```
public ZDD(int nodesize,
           int cachesize)
```
    create a Z-BDD manager
    
    Parameters:
    
    nodesize - is the number of nodes initially allocated in the node-table
    
    cachesize - is the suggested cache size.
- Method Detail
  - cleanup
```
public void cleanup()
```
    cleanup this ZDD, to release its memory and help GC
    
    Overrides:
    
    cleanup in class NodeTable
  - addDebugger
```
public Collection addDebugger(BDDDebuger d)
```
    Description copied from class: NodeTable
    
    for debugging: install a debugger. returns the set of caches.
    
    Overrides:
    
    addDebugger in class NodeTable
  - post_removal_callbak
```
protected void post_removal_callbak()
```
    Description copied from class: NodeTable
    
    this function is called when something in the node table is changed (GC or grow).
    sub-classes must "implement" this function for, for example, flushing caches since it signals that something important has been changed and old data might have become invalid.
    
    Overrides:
    
    post_removal_callbak in class NodeTable
  - mk
```
protected final int mk(int i,
                       int l,
                       int h)
```
    Zero-supressed MK operator
  - createVar
```
public int createVar()
```
    create a new ZDD variable
  - empty
```
public final int empty()
```
    returns {}
  - base
```
public final int base()
```
    returns {{}}
  - single
```
public final int single(int var)
```
    create a tree of a variable. single(vx) = { vx }
  - universe
```
public final int universe()
```
  - cube
```
public final int cube(int v)
```
    cube of a single variable v
  - cube
```
public final int cube(boolean[] v)
```
    cube of a selection of variables
  - cube
```
public final int cube(String s)
```
    cube of a selection of variables, represented as a string, e.g. "11001"
  - cubes_union
```
public int cubes_union(String s)
```
    Union of cubes, each represented by a string token. This function was added to ease fast creation of sets of sets in tests. E.g. "0001 1000 1101" => { v1, v4, v4v3v1 }
  - cubes_intersect
```
public int cubes_intersect(String s)
```
    Intersection of cubes. same as cubes_unon() but uses intersect instead of union
  - subsets
```
public int subsets(boolean[] v)
```
  - subset1
```
public final int subset1(int zdd,
                         int var)
```
    var is a variable, NOT a tree
  - subset0
```
public final int subset0(int zdd,
                         int var)
```
    var is a variable, NOT a tree
  - change
```
public final int change(int zdd,
                        int var)
```
  - union
```
public final int union(int p,
                       int q)
```
  - intersect
```
public final int intersect(int p,
                           int q)
```
  - diff
```
public final int diff(int p,
                      int q)
```
  - follow_low
```
public final int follow_low(int zdd)
```
    returns the terminal value along the all-low path
  - follow_high
```
public final int follow_high(int zdd)
```
    returns the terminal value along the all-high path
  - emptyIn
```
public final boolean emptyIn(int X)
```
    returns true if base {{}} is in X
  - satOne
```
public boolean[] satOne(int zdd,
                        boolean[] vec)
```
    Returns a satisfying boolean assignment, null if none
    XXX: this code is still untested!
  - count
```
public final int count(int zdd)
```
  - nodeCount
```
public int nodeCount(int zdd)
```
    compute the number of nodes in the tree (this function is currently somewhat slow)
  - unionTo
```
public int unionTo(int set,
                   int add)
```
    helper function to compute set' = set UNION add, derefs the old set!
  - diffTo
```
public int diffTo(int set,
                  int add)
```
    helper function to compute set' = set - add, derefs the old set!
  - showStats
```
public void showStats()
```
    show ZDD statistics
    
    Overrides:
    
    showStats in class NodeTable
  - getMemoryUsage
```
public long getMemoryUsage()
```
    return the amount of internally allocated memory in bytes
    
    Overrides:
    
    getMemoryUsage in class NodeTable
  - setNodeNames
```
public void setNodeNames(NodeName nn)
```
  - print
```
public void print(int zdd)
```
  - printDot
```
public void printDot(String fil,
                     int bdd)
```
  - printSet
```
public void printSet(int bdd)
```
  - printCubes
```
public void printCubes(int bdd)
```
  - internal_test
```
public static void internal_test()
```
    testbench. do not call

Class ZDD

Field Summary

Fields inherited from class jdd.bdd.NodeTable

Constructor Summary

Method Summary

Methods inherited from class jdd.bdd.NodeTable

Methods inherited from class java.lang.Object

Field Detail

num_vars

nodeNames

Constructor Detail

ZDD

ZDD

Method Detail

cleanup

addDebugger

post_removal_callbak

mk

createVar

empty

base

single

universe

cube

cube

cube

cubes_union

cubes_intersect

subsets

subset1

subset0

change

union

intersect

diff

follow_low

follow_high

emptyIn

satOne

count

nodeCount

unionTo

diffTo

showStats

getMemoryUsage

setNodeNames

print

printDot

printSet

printCubes

internal_test