You can use pure Python to do it:

    import json
    list = [1, 2, (3, 4)] # Note that the 3rd element is a tuple (3, 4)
    json.dumps(list) # &#39;[1, 2, [3, 4]]&#39;



If using Python 2.5, you may need to import `simplejson`: 

    try:
        import json
    except ImportError:
        import simplejson as json


Yes, but then what do you do about the django objects? simple json tends to choke on them. 

If the objects are individual model objects (not querysets, e.g.), I have occasionally stored the model object type and the pk, like so:

    seralized_dict = simplejson.dumps(my_dict, 
                         default=lambda a: &quot;[%s,%s]&quot; % (str(type(a)), a.pk)
                         )

to de-serialize, you can reconstruct the object referenced with model.objects.get(). This doesn&#39;t help if you are interested in the object details at the type the dict is stored, but it&#39;s effective if all you need to know is which object was involved.


I have a button like the following,

    &lt;asp:Button ID=&quot;pagerLeftButton&quot; runat=&quot;server&quot; OnClientClick=&quot;disable(this)&quot; onclick=&quot;pager_Left_Click&quot; Text=&quot;&lt;&quot; /&gt;

When I use my button like that, onclick is not firing. When I remove OnClientClick, then onclick is firing. 

What I need to do is, disable the button during the postback and enable it after the postback ends.


Edit:  Additional information: 

I added break point to my firing functions is c# part and I am debugging, they are not firing for sure. Those functions are like

    protected void pager_Left_Click(object sender, EventArgs e)
    {
    //Do smthing.
    }
    protected void pager_Right_Click(object sender, EventArgs e)
    {
    //Do smthing.
    }

and when I click my button, it is disabled for 1-2 seconds and automatically enabled, but I am not sure why it is enabled. I didn&#39;t add any part for it to be enabled again. 

OnclientClick and OnClick is not working at the same time?

    var arr= [&#39;g&#39;,&#39;o&#39;,&#39;o&#39;,&#39;d&#39;];
    var arr2 = arr.join();

Arr2 will be &quot;g,o,o,d&quot;. I would like to get &quot;good&quot;. I know there are a million other ways to achieve this but was curious if there was a way with join.

array join() method without a separator

I am sending information between client and Django server, and I would like to use JSON to this. I am sending simple information - list of strings. I tried using `django.core.serializers`, but when I did, I got 

    AttributeError: &#39;str&#39; object has no attribute &#39;_meta&#39;

It seems this can be used only for Django objects. How can I serialize simple, Python objects?


Serializing list to JSON

I am sending information between client and Django server, and I would like to use JSON to this. I am sending simple information - list of strings. I tried using <code>django.core.serializers</code>, but when I did, I got
<pre><code class="hljs language-csharp">AttributeError: 'str' object has no attribute '_meta'
</code></pre>
It seems this can be used only for Django objects. How can I serialize simple, Python objects?

I have a program that reads an XML document from a socket. I have the XML document stored in a string which I would like to convert directly to a Python dictionary, the same way it is done in Django&#39;s `simplejson` library.

Take as an example:

    str =&quot;&lt;?xml version=&quot;1.0&quot; ?&gt;&lt;person&gt;&lt;name&gt;john&lt;/name&gt;&lt;age&gt;20&lt;/age&gt;&lt;/person&quot;
    dic_xml = convert_to_dic(str)

Then `dic_xml` would look like `{&#39;person&#39; : { &#39;name&#39; : &#39;john&#39;, &#39;age&#39; : 20 } }`

How to convert an XML string to a dictionary?

I wrote a confusion matrix calculation code in Python:

    def conf_mat(prob_arr, input_arr):
            # confusion matrix
            conf_arr = [[0, 0], [0, 0]]
    
            for i in range(len(prob_arr)):
                    if int(input_arr[i]) == 1:
                            if float(prob_arr[i]) &lt; 0.5:
                                    conf_arr[0][1] = conf_arr[0][1] + 1
                            else:
                                    conf_arr[0][0] = conf_arr[0][0] + 1
                    elif int(input_arr[i]) == 2:
                            if float(prob_arr[i]) &gt;= 0.5:
                                    conf_arr[1][0] = conf_arr[1][0] +1
                            else:
                                    conf_arr[1][1] = conf_arr[1][1] +1
    
            accuracy = float(conf_arr[0][0] + conf_arr[1][1])/(len(input_arr))


prob_arr is an array that my classification code returned and a sample array is like this: 

     [1.0, 1.0, 1.0, 0.41592955657342651, 1.0, 0.0053405015805891975, 4.5321494433440449e-299, 1.0, 1.0, 1.0, 1.0, 1.0, 1.0, 0.70943426182688163, 1.0, 1.0, 1.0, 1.0]

input_arr is the original class labels for a dataset and it is like this: 

    [2, 1, 1, 1, 1, 1, 2, 1, 1, 2, 1, 1, 2, 1, 2, 1, 1, 1]

What my code is trying to do is: i get prob_arr and input_arr and for each class (1 and 2) I check if they are misclassified or not.

But my code only works for two classes. If I run this code for a multiple classed data, it doesn&#39;t work. How can I make this for multiple classes? 


For example, for a data set with three classes, it should return: `[[21,7,3],[3,38,6],[5,4,19]]`




 


How to write a confusion matrix in Python?

What is the most efficient way to rotate a list in python? 
Right now I have something like this:

    &gt;&gt;&gt; def rotate(l, n):
    ...     return l[n:] + l[:n]
    ... 
    &gt;&gt;&gt; l = [1,2,3,4]
    &gt;&gt;&gt; rotate(l,1)
    [2, 3, 4, 1]
    &gt;&gt;&gt; rotate(l,2)
    [3, 4, 1, 2]
    &gt;&gt;&gt; rotate(l,0)
    [1, 2, 3, 4]
    &gt;&gt;&gt; rotate(l,-1)
    [4, 1, 2, 3]

Is there a better way?



Efficient way to rotate a list in python

I have a file. In Python, I would like to take its creation time, and convert it to an [ISO time (ISO 8601) string][1] **while preserving the fact that it was created in the [Eastern Time Zone][2] (ET)**.

How do I take the file&#39;s ctime and convert it to an ISO time string that indicates the Eastern Time Zone (and takes into account daylight savings time, if necessary)?

  [1]: http://en.wikipedia.org/wiki/ISO_8601
  [2]: https://en.wikipedia.org/wiki/Eastern_Time_Zone


ISO time (ISO 8601) in Python

I have a list of lists:

    lists = [[1,4,3,2,4], [4,5]]

I want to flatten this list and remove all duplicates; or, in other words, apply a set union operation:

    desired_result = [1, 2, 3, 4, 5]

What&#39;s the easiest way to do this? 


Pythonic way to create union of all values contained in multiple lists

I have a django admin interface and in the model listing I want a custom column that will be a hyperlink using one of the fields values.  Basically one of the models&#39; fields is a url and i&#39;d like the column to have that URL in a clickable hyperlink.  This link will need to have additional URL prepended to it as its a relative path in the model field.

How do I add a custom column with a hyperlink in the django admin interface?

My code in myapp_extras.py:

    from django import template
    
    register = template.Library()
    
    @register.inclusion_tag(&#39;new/userinfo.html&#39;)
    def address():
    	address = request.session[&#39;address&#39;]
    	return {&#39;address&#39;:address}

in &#39;settings.py&#39;:

    TEMPLATE_CONTEXT_PROCESSORS =(
    	&quot;django.core.context_processors.auth&quot;,
    	&quot;django.core.context_processors.debug&quot;,
    	&quot;django.core.context_processors.i18n&quot;,
    	&quot;django.core.context_processors.media&quot;,
    	&#39;django.core.context_processors.request&#39;
    )


but I got an error:

    TemplateSyntaxError at /items/
    
    Caught an exception while rendering: global name &#39;request&#39; is not defined
    
    Original Traceback (most recent call last):
      File &quot;C:\Python25\lib\site-packages\django\template\debug.py&quot;, line 71, in render_node
        result = node.render(context)
      File &quot;C:\Python25\lib\site-packages\django\template\__init__.py&quot;, line 915, in render
        dict = func(*args)
      File &quot;C:\p4\projects\myproject\..\myproject\invoice\templatetags\myapp_extras.py&quot;, line 9, in address
        address = request.session[&#39;address&#39;]
    NameError: global name &#39;request&#39; is not defined

I referenced this one
https://stackoverflow.com/questions/335231/in-django-is-it-possible-to-access-the-current-user-session-from-within-a-custom.


Access request in django custom template tags

I&#39;m trying to find a way to implement both a custom `QuerySet` and a custom `Manager` without breaking DRY.  This is what I have so far:

    class MyInquiryManager(models.Manager):
        def for_user(self, user):
            return self.get_query_set().filter(
                        Q(assigned_to_user=user) |
                        Q(assigned_to_group__in=user.groups.all())
                    )
    
    class Inquiry(models.Model):   
        ts = models.DateTimeField(auto_now_add=True)
        status = models.ForeignKey(InquiryStatus)
        assigned_to_user = models.ForeignKey(User, blank=True, null=True)
        assigned_to_group = models.ForeignKey(Group, blank=True, null=True)
        objects = MyInquiryManager()

This works fine, until I do something like this:

    inquiries = Inquiry.objects.filter(status=some_status)
    my_inquiry_count = inquiries.for_user(request.user).count()

This promptly breaks everything because the `QuerySet` doesn&#39;t have the same methods as the `Manager`.  I&#39;ve tried creating a custom `QuerySet` class, and implementing it in `MyInquiryManager`, but I end up replicating all of my method definitions.

I also found [this snippet][1] which works, but I need to pass in the extra argument to `for_user` so it breaks down because it relies heavily on redefining `get_query_set`.

Is there a way to do this without redefining all of my methods in both the `QuerySet` and the `Manager` subclasses?


  [1]: http://adam.gomaa.us/blog/2009/feb/16/subclassing-django-querysets/

Custom QuerySet and Manager without breaking DRY?

I&#39;m working on a large Django app, the vast majority of which requires a login to access.  This means that all throughout our app we&#39;ve sprinkled:

    @login_required
    def view(...):

That&#39;s fine, and it works great *as long as we remember to add it everywhere*!  Sadly sometimes we forget, and the failure often isn&#39;t terribly evident.  If the only link to a view is on a @login_required page then you&#39;re not likely to notice that you can actually reach that view without logging in.  But the bad guys might notice, which is a problem.

My idea was to reverse the system.  Instead of having to type @login_required everywhere, instead I&#39;d have something like:

    @public
    def public_view(...):

Just for the public stuff.  I tried to implement this with some middleware and I couldn&#39;t seem to get it to work.  Everything I tried interacted badly with other middleware we&#39;re using, I think.  Next up I tried writing something to traverse the URL patterns to check that everything that&#39;s not @public was marked @login_required - at least then we&#39;d get a quick error if we forgot something.  But then I couldn&#39;t figure out how to tell if @login_required had been applied to a view...

So, what&#39;s the right way to do this?  Thanks for the help!

Best way to make Django&#39;s login_required the default

When writing django queries one can use both id/pk as query parameters.

    Object.objects.get(id=1)
    Object.objects.get(pk=1)


I know that pk stands for Primary Key and is just a shortcut, according to django&#39;s documentation. However it is not clear when one should be using id or pk.

Django queries - id vs pk

I have to do something very simple, but there doesn&#39;t seem to be an easy way to do this, as far as I can tell. I just want to load JSON data from a remote source and store it in a global Javascript variable using jQuery. Here&#39;s what I have:

    var my_json;
    $.getJSON(my_url, function(json) {
      var my_json = json;
    });

The my_json variable remains undefined. I think this is clearly a scope issue. It seems to me the $.getJSON method should return JSON, but it returns an XMLHttpRequest object. If I do this:

    request = $.getJSON(my_url);
    my_json = request.responseText.evalJSON();

That doesn&#39;t work because until the readystate == 4, the responsetext remains null. It seems you have to use the callback function to return the responsetext, since it fires on success.

It can&#39;t be this hard! Right?
 




load json into variable

I&#39;m using Jersey to create a REST web service for a server component.

The JAXB-annotated object I want to serialize in a list looks like this:

    @XmlRootElement(name = &quot;distribution&quot;)
    @XmlType(name = &quot;tDistribution&quot;, propOrder = {
        &quot;id&quot;, &quot;name&quot;
    })
    public class XMLDistribution {
        private String id;
        private String name;
        // no-args constructor, getters, setters, etc
    }

I have a REST resource to retrieve one distribution which looks like this:

    @Path(&quot;/distribution/{id: [1-9][0-9]*}&quot;)
    public class RESTDistribution {
        @GET
        @Produces(&quot;application/json&quot;)
        public XMLDistribution retrieve(@PathParam(&quot;id&quot;) String id) {
            return retrieveDistribution(Long.parseLong(id));
        }
        // business logic (retrieveDistribution(long))
    }

I also have a REST resource to retrieve a list of all distributions, which looks like this:

    @Path(&quot;/distributions&quot;)
    public class RESTDistributions {
        @GET
        @Produces(&quot;application/json&quot;)
        public List&lt;XMLDistribution&gt; retrieveAll() {
            return retrieveDistributions();
        }
        // business logic (retrieveDistributions())
    }

I use a ContextResolver to customize JAXB serialization, which is currently configured like this:

    @Provider
    @Produces(&quot;application/json&quot;)
    public class JAXBJSONContextResolver implements ContextResolver&lt;JAXBContext&gt; {
        private JAXBContext context;
        public JAXBJSONContextResolver() throws Exception {
            JSONConfiguration.MappedBuilder b = JSONConfiguration.mapped();
            b.nonStrings(&quot;id&quot;);
            b.rootUnwrapping(true);
            b.arrays(&quot;distribution&quot;);
            context = new JSONJAXBContext(b.build(), XMLDistribution.class);
        }
        @Override
        public JAXBContext getContext(Class&lt;?&gt; objectType) {
            return context;
        }
    }

Both REST resources work, as well as the context resolver. This is an example of output for the first one:

```
// path: /distribution/1
{
  &quot;id&quot;: 1,
  &quot;name&quot;: &quot;Example Distribution&quot;
}
```

Which is exactly what I want. This is an example of output for the list:

```
// path: /distributions
{
  &quot;distribution&quot;: [{
    &quot;id&quot;: 1,
    &quot;name&quot;: &quot;Sample Distribution 1&quot;
  }, {
    &quot;id&quot;: 2,
    &quot;name&quot;: &quot;Sample Distribution 2&quot;
  }]
}
```

Which is not quite what I want.

I don&#39;t understand why there is an enclosing &lt;code&gt;distribution&lt;/code&gt; tag there. I wanted to remove it with &lt;code&gt;.rootUnwrapping(true)&lt;/code&gt; in the context resolver, but apparently that only removes another enclosing tag. This is the output with &lt;code&gt;.rootUnwrapping(false)&lt;/code&gt;:

```
// path: /distribution/1
{
  &quot;distribution&quot;: {
    &quot;id&quot;: 1,
    &quot;name&quot;: &quot;Example Distribution&quot;
  }
} // not ok
// path: /distributions
{
  &quot;xMLDistributions&quot;: {
    &quot;distribution&quot;: [{
      &quot;id&quot;: 1,
      &quot;name&quot;: &quot;Sample Distribution 1&quot;
    }, {
      &quot;id&quot;: 2,
      &quot;name&quot;: &quot;Sample Distribution 2&quot;
    }]
  }
}
```

I also had to configure &lt;code&gt;.arrays(&quot;distribution&quot;)&lt;/code&gt; to always get a JSON array, even with only one element.

Ideally, I&#39;d like to have this as an output:

```
// path: /distribution/1
{
  &quot;id&quot;: 1,
  &quot;name&quot;: &quot;Example Distribution&quot;
} // currently works
// path: /distributions
[{
  &quot;id&quot;: 1,
  &quot;name&quot;: &quot;Sample Distribution 1&quot;
}, {
  &quot;id&quot;: 2,
  &quot;name&quot;: &quot;Sample Distribution 2&quot;
}]
```

I tried to return a &lt;code&gt;List&amp;lt;XMLDistribution&amp;gt;&lt;/code&gt;, a &lt;code&gt;XMLDistributionList&lt;/code&gt; (wrapper around a list), a &lt;code&gt;XMLDistribution[]&lt;/code&gt;, but I couldn&#39;t find a way to get a simple JSON array of distributions in my required format.

I also tried the other notations returned by &lt;code&gt;JSONConfiguration.natural()&lt;/code&gt;, &lt;code&gt;JSONConfiguration.mappedJettison()&lt;/code&gt;, etc, and couldn&#39;t get anything resembling what I need.

Does anyone know if it is possible to configure JAXB to do this?

How can I customize serialization of a list of JAXB objects to JSON?

Is there an easy way to populate my C# Object with the JSON object passed via AJAX?

This is the JSON Object passed to C# WEBMETHOD from the page using JSON.stringify

```json
{
	&quot;user&quot;: {
		&quot;name&quot;: &quot;asdf&quot;,
		&quot;teamname&quot;: &quot;b&quot;,
		&quot;email&quot;: &quot;c&quot;,
		&quot;players&quot;: [&quot;1&quot;, &quot;2&quot;]
	}
}
```

C# WebMetod That receives the JSON Object

```lang-cs
[WebMethod]
public static void SaveTeam(Object user)
{

}
```

C# Class that represents the object structure of JSON Object passed in to the WebMethod

```lang-cs
public class User
{
	public string name { get; set; }
	public string teamname { get; set; }
	public string email { get; set; }
	public Array players { get; set; }
}
```

How to Convert JSON object to Custom C# object?

I am trying the create the following:

```
var employees = {
  &quot;accounting&quot;: [ // accounting is an array in employees.
    {
      &quot;firstName&quot;: &quot;John&quot;, // First element
      &quot;lastName&quot;: &quot;Doe&quot;,
      &quot;age&quot;: 23
    },

    {
      &quot;firstName&quot;: &quot;Mary&quot;, // Second Element
      &quot;lastName&quot;: &quot;Smith&quot;,
      &quot;age&quot;: 32
    }
  ] // End &quot;accounting&quot; array.                                  

} // End Employees
```

I started with

     var employees = new Array();

How do I continue to create the array dynamically (might change `firstName` with variable)? I don&#39;t seem to get the nested array right.

How do I create JavaScript array (JSON format) dynamically?

I have read quite a number of articles on Serialization and how it is so nice and great but none of the arguments were convincing enough. I am wondering if someone can really tell me what is it that we can really achieve by serializing a class?


What is the purpose of Serialization in Java?

I have a class definition that contains a property that returns an interface.

    public class Foo
    { 
        public int Number { get; set; }

        public ISomething Thing { get; set; }
    }

Attempting to serialize the Foo class using Json.NET gives me an error message like, &quot;Could not create an instance of type &#39;ISomething&#39;. ISomething may be an interface or abstract class.&quot;

Is there a Json.NET attribute or converter that would let me specify a concrete `Something` class to use during deserialization?

Using Json.NET converters to deserialize properties

I want to serialize DOM node or even whole `window` to JSON.

For example:

     &gt;&gt; serialize(document)
        -&gt; {
          &quot;URL&quot;: &quot;http://stackoverflow.com/posts/2303713&quot;,
          &quot;body&quot;: {
            &quot;aLink&quot;: &quot;&quot;,
            &quot;attributes&quot;: [
              &quot;getNamedItem&quot;: &quot;function getNamedItem() { [native code] }&quot;,
              ...
            ],
            ...
            &quot;ownerDocument&quot;: &quot;#&quot; // recursive link here
          },
          ...
        }
     
    
JSON.stringify()
----------------
    
    JSON.stringify(window) // TypeError: Converting circular structure to JSON

The problem is JSON does not support circular references by default.

    var obj = {}
    obj.me = obj
    JSON.stringify(obj) // TypeError: Converting circular structure to JSON

`window` and DOM nodes have many of them. `window === window.window` as will as `document.body.ownerDocument === document`.

Also, `JSON.stringify` does not serialize functions, so this is not what I&#39;m looking for.

[dojox.json.ref](http://www.sitepen.com/blog/2008/06/17/json-referencing-in-dojo)
----------------

     `dojox.json.ref.toJson()` can easily serialize object with circular references:
    
        var obj = {}
        obj.me = obj
        dojox.json.ref.toJson(obj); // {&quot;me&quot;:{&quot;$ref&quot;:&quot;#&quot;}}

 
Good, isn&#39;t it?

   

     dojox.json.ref.toJson(window) // Error: Can&#39;t serialize DOM nodes

Well not good enough for me.

Why?
----

I&#39;m trying to make DOM compatibility table for different browsers. For instance, Webkit supports placeholder attribute and Opera doesn&#39;t, IE 8 supports `localStorage` and IE 7 doesn&#39;t, and so on.

I don&#39;t want to make thousands of test-cases. I want to make generic way for test them all.

Update, June 2013
---------

I made a prototype **[NV/dom-dom-dom.com](https://github.com/NV/dom-dom-dom.com)**.




How to serialize DOM node to JSON even if there are circular references?

I&#39;m trying to read / write multiple Protocol Buffers messages from files, in both C++ and Java. Google suggests writing length prefixes before the messages, but there&#39;s no way to do that by default (that I could see).

However, the Java API in version 2.1.0 received a set of &quot;Delimited&quot; I/O functions which apparently do that job: 

    parseDelimitedFrom
    mergeDelimitedFrom
    writeDelimitedTo

Are there C++ equivalents? And if not, what&#39;s the wire format for the size prefixes the Java API attaches, so I can parse those messages in C++?

---
### Update: 
These now exist in [`google/protobuf/util/delimited_message_util.h`](https://github.com/protocolbuffers/protobuf/blob/master/src/google/protobuf/util/delimited_message_util.h) as of v3.3.0.

Content Type	Original Author	Original Content on Stackoverflow
Question	gruszczy	View Question on Stackoverflow
Solution 1 - Python	Emil Ivanov	View Answer on Stackoverflow
Solution 2 - Python	reech	View Answer on Stackoverflow
Solution 3 - Python	adobelis	View Answer on Stackoverflow

Serializing list to JSON

Python Problem Overview

Python Solutions

Solution 1 - Python

Solution 2 - Python

Solution 3 - Python

array join() method without a separator

OnclientClick and OnClick is not working at the same time?

Attributions