在perl中的Graphviz2保存圖形圖像

Question

我想輸出使用GraphViz2 perl模塊生成的圖形到文件。我有下一個代碼，但它不保存圖像。我怎樣才能保存它？

my $output_dir = "/home/user/Desktop/output.png"; 

my($graph) = GraphViz2 -> new(); 

       (
       edge => {color => 'grey'}, 
       global => {directed => 1}, 
       graph => {label => 'Adult', rankdir => 'TB'}, 
       logger => $logger, 
       node => {shape => 'oval'}, 
       ); 

     $graph -> add_node(name => 'Carnegie', shape => 'circle'); 
     $graph -> add_node(name => 'Murrumbeena', shape => 'box', color => 'green'); 
     $graph -> add_node(name => 'Oakleigh', color => 'blue'); 

     $graph -> add_edge(from => 'Murrumbeena', to => 'Carnegie', arrowsize => 2); 
     $graph -> add_edge(from => 'Murrumbeena', to => 'Oakleigh', color => 'brown'); 





my($format)  = shift || 'png'; 
my($output_dir) = shift || File::Spec -> catfile('png', "sub.graph.$format"); 

$graph -> run(format => $format, output_file => $output_file); 

Answer 1

my($output_dir) = shift || File::Spec -> catfile('png', "sub.graph.$format"); 

應該

my($output_file) = shift || File::Spec -> catfile('html', "sub.graph.$format"); 

你的代碼有沒有$output_file你從什麼地方出現了拼寫錯誤或複製/粘貼代碼不正確。