You want to specify the `target` keyword parameter instead:

    t1 = threading.Thread(target=analysis(&quot;samplequery&quot;))

You probably meant to make `analysis` the run target, but `&#39;samplequery` the argument *when started*:

    t1 = threading.Thread(target=analysis, args=(&quot;samplequery&quot;,))

The first parameter to `Thread()` is the `group` argument, and it currently only accepts `None` as the argument.

From the [`threading.Thread()` documentation](http://docs.python.org/2/library/threading.html#threading.Thread):

&gt;  This constructor should always be called with keyword arguments. Arguments are:
&gt;
&gt; * *group* should be `None`; reserved for future extension when a `ThreadGroup` class is implemented.
&gt; * *target* is the callable object to be invoked by the `run()` method. Defaults to `None`, meaning nothing is called.


You need to provide the `target` attribute:

    t1 = threading.Thread(target = analysis, args = (&#39;samplequery&#39;,))

When I do this in my node.js module:

    var abc = &#39;123&#39;;

Where does it go? And by this I mean: in the browser it goes in `window.abc` (if not executed in a function or otherwise)

If I execute this:

    abc = &#39;123&#39;;

Then I can find it in `global.abc`, but that&#39;s not how I want it.

In what scope are module variables stored in node.js?

I have the following configuration:

    &lt;bean id=&quot;entityManagerFactory&quot;
    		class=&quot;org.springframework.orm.jpa.LocalContainerEntityManagerFactoryBean&quot;&gt;
    		&lt;property name=&quot;dataSource&quot; ref=&quot;jpaDataSource&quot; /&gt;
    		&lt;property name=&quot;jpaVendorAdapter&quot;&gt;
    			&lt;bean class=&quot;org.springframework.orm.jpa.vendor.HibernateJpaVendorAdapter&quot; /&gt;
    		&lt;/property&gt;
    		&lt;property name=&quot;jpaProperties&quot;&gt;
    			&lt;props&gt;
    				&lt;prop key=&quot;hibernate.dialect&quot;&gt;org.hibernate.dialect.MySQLDialect&lt;/prop&gt;
    				&lt;prop key=&quot;hibernate.show_sql&quot;&gt;true&lt;/prop&gt;
    			&lt;/props&gt;
    		&lt;/property&gt;
    		&lt;property name=&quot;packagesToScan&quot;&gt;
            &lt;list&gt;
                &lt;value&gt;com.example.domain&lt;/value&gt;
                &lt;value&gt;com.example.repositories&lt;/value&gt;
            &lt;/list&gt;
        &lt;/property&gt;
    &lt;/bean&gt;

I have my Geoname class in com.example.domain:

    @Entity
    @Table(name=&quot;geonames&quot;)
    public class Geoname implements Serializable {
    
    	@Id
    	@Column(name=&quot;geonameid&quot;)
    	private Long geonameid = null;
    }

yet, when running, I get the following exception:

&gt; Caused by: org.hibernate.AnnotationException: No identifier specified
&gt; for entity: com.example.domain.Geoname 	at
&gt; org.hibernate.cfg.InheritanceState.determineDefaultAccessType(InheritanceState.java:277)
&gt; 	at
&gt; org.hibernate.cfg.InheritanceState.getElementsToProcess(InheritanceState.java:224)
&gt; 	at
&gt; org.hibernate.cfg.AnnotationBinder.bindClass(AnnotationBinder.java:664)
&gt; 	at
&gt; org.hibernate.cfg.Configuration$MetadataSourceQueue.processAnnotatedClassesQueue(Configuration.java:3449)
&gt; 	at
&gt; org.hibernate.cfg.Configuration$MetadataSourceQueue.processMetadata(Configuration.java:3403)
&gt; 	at
&gt; org.hibernate.cfg.Configuration.secondPassCompile(Configuration.java:1330)
&gt; 	at
&gt; org.hibernate.cfg.Configuration.buildSessionFactory(Configuration.java:1730)

Any ideas why?

side note: I am combining both mongodb and hibernate/ mysql on this project.

org.hibernate.AnnotationException: No identifier specified for entity - even when it was

I&#39;m trying to run some simple threading in Python using:

    t1 = threading.Thread(analysis(&quot;samplequery&quot;))
    t1.start()
    
    other code runs in here

    t1.join()

Unforunately I&#39;m getting the error:

&gt; &quot;AssertionError: group argument must be none for now&quot;

I&#39;ve never implemented threading in Python before, so I&#39;m a bit unsure as to what&#39;s going wrong. Does anyone have any idea what the problem is? 

I&#39;m not sure if it&#39;s relevant at all, but analysis is a method imported from another file.

I had one follow up query as well. Analysis returns a dictionary, how would I go about assigning that for use in the original method?

Thanks

AssertionError when threading in Python

I'm trying to run some simple threading in Python using:
<pre><code class="hljs language-ini">t1 = threading.Thread(analysis("samplequery"))
t1.start()

other code runs in here

t1.join()
</code></pre>
Unforunately I'm getting the error:
> "AssertionError: group argument must be none for now"
I've never implemented threading in Python before, so I'm a bit unsure as to what's going wrong. Does anyone have any idea what the problem is?
I'm not sure if it's relevant at all, but analysis is a method imported from another file.
I had one follow up query as well. Analysis returns a dictionary, how would I go about assigning that for use in the original method?
Thanks

I am generating an XML document in Python using an [`ElementTree`][1], but the `tostring` function doesn&#39;t include an [XML declaration][2] when converting to plaintext.

&lt;!-- language: lang-python --&gt;

    from xml.etree.ElementTree import Element, tostring

    document = Element(&#39;outer&#39;)
    node = SubElement(document, &#39;inner&#39;)
    node.NewValue = 1
    print tostring(document)  # Outputs &quot;&lt;outer&gt;&lt;inner /&gt;&lt;/outer&gt;&quot;

I need my string to include the following XML declaration:

&lt;!-- language: lang-xml--&gt;

    &lt;?xml version=&quot;1.0&quot; encoding=&quot;UTF-8&quot; standalone=&quot;yes&quot; ?&gt;

However, there does not seem to be any documented way of doing this.

Is there a proper method for rendering the XML declaration in an `ElementTree`?


  [1]: https://docs.python.org/2/library/xml.etree.elementtree.html
  [2]: http://xmlwriter.net/xml_guide/xml_declaration.shtml

How to write XML declaration using xml.etree.ElementTree

I tried:

    x=pandas.DataFrame(...)
    s = x.take([0], axis=1)

And `s` gets a DataFrame, not a Series.

How to get the first column of a pandas DataFrame as a Series?

Here&#39;s the Python code I&#39;m having problems with:

    for i in range (0,10):
        if i==5:
            i+=3
        print i

I expected the output to be:

    0
    1
    2
    3
    4
    8
    9

However, the interpreter spits out:

    0
    1
    2
    3
    4
    8
    6
    7
    8
    9

I know that a `for` loop creates a new scope for a variable in C, but have no idea about Python. Why does the value of `i` not change in the `for` loop in Python, and what&#39;s the remedy to it to get the expected output?

Scope of python variable in for loop

I&#39;m currently learning Python and Classes and I have a basic question, but I didn&#39;t find any answer to it. Let&#39;s say I have this dummy class

	class DomainOperations:
		def __init__(self, domain):
			self.domain = domain
			self.domain_ip = &#39;&#39;
			self.website_thumbnail = &#39;&#39;
		
		def resolve_domain(self):
			#resolve domain to ipv4 and save to self.domain_ip
			
		def generate_website_thumbnail(self):
			#generate website thumbnail and save the url to self.website_thumbnail

I want to run simultaneously resolve_domain and generate_website_thumbnail and when the threads are finished I want to print the IP and the thumbnail. 

**EDIT:** I know I should use threads, maybe something like this

	r = DomainOperations(&#39;google.com&#39;)

	t1 = threading.Thread(target=r.resolve_domain)
	t1.start()

	t2 = threading.Thread(target=r.generate_website_thumbnail)
	t2.start()


But should I use them outside the Class? Should I write another Class to handle Threads?

What is the **right way** to do that?

Run Class methods in threads (python)

Can someone explain why the result I want, &quot;hi&quot;, is preceded with a letter &#39;b&#39; and followed with a newline?  

I am using **Python 3.3**

    &gt;&gt;&gt; import subprocess
    &gt;&gt;&gt; print(subprocess.Popen(&quot;echo hi&quot;, shell=True,
                               stdout=subprocess.PIPE).communicate()[0])
    b&#39;hi\n&#39;

This extra &#39;b&#39; does not appear if I run it with python 2.7

Why does Popen.communicate() return b&#39;hi\n&#39; instead of &#39;hi&#39;?

The [accepted answer to question &quot;Why does this Parallel.ForEach code freeze the program up?&quot;][1] advises to substitute the List usage by [ConcurrentBag][2] in a WPF application.  

I&#39;d like to understand whether a [BlockingCollection&lt;T&gt;][3] can be used in this case instead?   


  [1]: https://stackoverflow.com/a/8365614/2031316
  [2]: http://msdn.microsoft.com/en-us/library/dd381779.aspx
  [3]: http://msdn.microsoft.com/en-us/library/dd267312%28v=vs.100%29.aspx

When to use BlockingCollection and when ConcurrentBag instead of List&lt;T&gt;?

If I synchronized two methods on the same class, can they run simultaneously **on the same object**? For example:

    class A {
    	public synchronized void methodA() {
    		//method A
    	}
    
    	public synchronized void methodB() {
    		// method B
    	}
    }

I know that I can&#39;t run `methodA()` twice on same object in two different threads. same thing in `methodB()`.

But can I run `methodB()` on different thread while `methodA()` is still running? (same object)

If I synchronized two methods on the same class, can they run simultaneously?

I want some code to run in the background continuously. I don&#39;t want to do it in a service. Is there any other way possible? 

I have tried calling the `Thread` class in my `Activity` but my `Activity` remains in the background for sometime and then it stops. The `Thread` class also stops working.
   
	class testThread implements Runnable {
		    @Override
		    public void run() {
		        File file = new File( Environment.getExternalStorageDirectory(), &quot;/BPCLTracker/gpsdata.txt&quot; );
		        int i = 0;

		        RandomAccessFile in = null;

		        try {
		            in = new RandomAccessFile( file, &quot;rw&quot; );
		        } catch (FileNotFoundException e) {
	// TODO Auto-generated catch block
		            e.printStackTrace();
		        } catch (IOException e) {
	// TODO Auto-generated catch block
		            e.printStackTrace();
		        }
	//String line =null;
		        while ( true ) {
		            HttpEntity entity = null;
		            try {
		                if ( isInternetOn() ) {
		                    while ( ( line = in.readLine() ) != null ) {

		                        HttpClient client = new DefaultHttpClient();
		                        String url = &quot;some url&quot;;
		                        HttpPost request = new HttpPost( url );
		                        StringEntity se = new StringEntity( line );
		                        se.setContentEncoding( &quot;UTF-8&quot; );
		                        se.setContentEncoding( new BasicHeader( HTTP.CONTENT_TYPE, &quot;application/json&quot; ) );
		                        entity = se;
		                        request.setEntity( entity );
		                        HttpResponse response = client.execute( request );
		                        entity = response.getEntity();
		                        i++;
		                    }
		                    if ( ( line = in.readLine() ) == null &amp;&amp; entity != null ) {
		                        file.delete();
		                        testThread t = new testThread();
		                        Thread t1 = new Thread( t );
		                        t1.start();
		                    }


		                } else {
		                    Thread.sleep( 60000 );
		                } // end of else

		            } catch (NullPointerException e1) {
		                e1.printStackTrace();
		            } catch (InterruptedException e2) {
		                e2.printStackTrace();
		            } catch (IOException e1) {
	// TODO Auto-generated catch block
		                e1.printStackTrace();
		            }
		        }// end of while
		    }// end of run

		}
	


How can I run code on a background thread on Android?

I&#39;ve already read previous questions here about `ConcurrentBag` but did not find an actual sample of implementation in multi-threading.

&gt;ConcurrentBag is a thread-safe bag implementation, optimized for scenarios where the same thread will be both producing and consuming data stored in the bag.&quot;

Currently this is the current usage in my code (this is simplified not actual codes):

    private void MyMethod()
    {
        List&lt;Product&gt; products = GetAllProducts(); // Get list of products
        ConcurrentBag&lt;Product&gt; myBag = new ConcurrentBag&lt;Product&gt;();

        //products were simply added here in the ConcurrentBag to simplify the code
        //actual code process each product before adding in the bag
        Parallel.ForEach(
					products,
					new ParallelOptions { MaxDegreeOfParallelism = Environment.ProcessorCount },
					product =&gt; myBag.Add(product));

		ProcessBag(myBag); // method to process each items in the concurrentbag
    }
     

My questions:  
Is this the right usage of `ConcurrentBag`? Is it ok to use `ConcurrentBag` in this kind of scenario?

For me I think a simple `List&lt;Product&gt;` and a manual lock will do better. The reason for this is that the scenario above already breaks the &quot;**same thread will be both producing and consuming data stored in the bag**&quot; rule.  
Also I also found out that the `ThreadLocal` storage created in each thread in the parallel will still exist after the operation (even if the thread is reused is this right?) which may cause an undesired memory leak.  
Am I right in this one guys? Or a simple clear or empty method to remove the items in the `ConcurrentBag` is enough?  


Content Type	Original Author	Original Content on Stackoverflow
Question	djcmm476	View Question on Stackoverflow
Solution 1 - Python	Martijn Pieters	View Answer on Stackoverflow
Solution 2 - Python	g.d.d.c	View Answer on Stackoverflow

AssertionError when threading in Python

Python Problem Overview

Python Solutions

Solution 1 - Python

Solution 2 - Python

org.hibernate.AnnotationException: No identifier specified for entity - even when it was

In what scope are module variables stored in node.js?

Attributions