File:BDD Variable Ordering Good.png

File:BDD Variable Ordering Good.svg is a vector version of this file. It should be used in place of this PNG file. File:BDD Variable Ordering Good.png → File:BDD Variable Ordering Good.svg For more information, see Help:SVG. In other languages Alemannisch ∙ العربية ∙ беларуская (тарашкевіца) ∙ български ∙ বাংলা ∙ català ∙ нохчийн ∙ čeština ∙ dansk ∙ Deutsch ∙ Ελληνικά ∙ English ∙ British English ∙ Esperanto ∙ español ∙ eesti ∙ euskara ∙ فارسی ∙ suomi ∙ français ∙ Frysk ∙ galego ∙ Alemannisch ∙ עברית ∙ hrvatski ∙ magyar ∙ հայերեն ∙ Bahasa Indonesia ∙ Ido ∙ italiano ∙ 日本語 ∙ ქართული ∙ 한국어 ∙ lietuvių ∙ македонски ∙ മലയാളം ∙ Bahasa Melayu ∙ norsk bokmål ∙ Plattdüütsch ∙ Nederlands ∙ norsk nynorsk ∙ norsk ∙ occitan ∙ polski ∙ prūsiskan ∙ português ∙ português do Brasil ∙ română ∙ русский ∙ sicilianu ∙ Scots ∙ slovenčina ∙ slovenščina ∙ српски / srpski ∙ svenska ∙ தமிழ் ∙ ไทย ∙ Türkçe ∙ татарча / tatarça ∙ українська ∙ vèneto ∙ Tiếng Việt ∙ 中文 ∙ 中文（中国大陆） ∙ 中文（简体） ∙ 中文（繁體） ∙ 中文（马来西亚） ∙ 中文（新加坡） ∙ 中文（臺灣） ∙ 中文（臺灣） ∙ +/−

 

The PNG picture is 156 x 435 pixel.

Other BDD pictures for similar formulas:

• 
  BDD graph for the Boolean formula x1 * x2 + x3 * x4 + x5 * x6 + x7 * x8 using a bad variable ordering
• 
  Visualization of the BDD for the Boolean formula x1 * x2 + x3 * x4 + ... + x19 * x20 using a bad variable ordering

The following is the RML (Relational Manipulation Language) code that I fed to CrocoPat to produce the GraphViz dot files:

// RML program to generate BDD graphs for the formula
// x1 & x2 | x3 & x4 | x5 & x6 | x7 & x8,
// using two different variable orderings.
// "crocopat -e BDD_Variable_Ordering.rml" generates two files in dot format.
// "dot -Tsvg BDD_Variable_Ordering_Bad.dot -o BDD_Variable_Ordering_Bad.svg"
// generates a file in SVG format from the file in dot format.

// There are two ('Boolean') values for the variables x1, ..., x8.
DOM("0");
DOM("1");

// F is the name of the Boolean formula.
F(x1,x2,x3,x4,x5,x6,x7,x8) :=  (x1="1" & x2="1") 
                             | (x3="1" & x4="1")
                             | (x5="1" & x6="1")
                             | (x7="1" & x8="1");

// Prints the BDD as graph in GraphViz dot format,
// using a good variable ordering resulting in linear size of the graph.
PRINT GRAPH( F(x1,x2,x3,x4,x5,x6,x7,x8) ) 
      TO "BDD_Variable_Ordering_Good.dot";

// Prints the BDD as graph in GraphViz dot format,
// using a bad variable ordering resulting in exponential size of the graph.
// The first term of the conjunction sets the variable ordering.
PRINT GRAPH( TRUE(x1,x3,x5,x7,x2,x4,x6,x8) &
             F(x1,x2,x3,x4,x5,x6,x7,x8) ) 
      TO "BDD_Variable_Ordering_Bad.dot";;

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• share alike – If you remix, transform, or build upon the material, you must distribute your contributions under the same or compatible license as the original.

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