The PIL distribution is mispackaged for egg installation.

Install [Pillow](http://pillow.readthedocs.org/en/latest/) instead, the friendly PIL fork.

On a system with both Python 2 and 3 installed and with `pip2`-installed Pillow failing to provide `Image`, it is possible to install PIL for Python 2 in a way that will solve `ImportError: No module named Image`:

    easy_install-2.7 --user PIL

or

    sudo easy_install-2.7 PIL

I&#39;m trying to update my PHP (currently v:5.3.3 to the latest stable PHP build) but it&#39;s not playing ball and it&#39;s saying there is nothing to update.

Any help would be useful.

Keeps saying:

&gt; No Packages marked for Update

Upgrading PHP on CentOS 6.5 (Final)

How do I write this multi-line, complex condition if statement in Ruby?

      if ( (aa != nil &amp;&amp; self.prop1 == aa.decrypt)   
          || (bb != nil &amp;&amp; self.prop2 == bb.decrypt)  
        ) &amp;&amp; (self.id.nil? || self.id != id) 
        return true
      end

I&#39;m getting `Syntax error; unexpected tOROP`.


In Java, I could write

    if (
         ( (aa != null &amp;&amp; aa.prop1.equals(aa.decrypt()))
         || (bb != null &amp;&amp; bb.prop2.equals(bb.decrypt()))
         )
         &amp;&amp; (this.id != id)
       ) {
      
       return true;
    }



How do I write a complex multi-line if condition in Ruby?

I have also tried 

    from PIL import Image

but it gives me ImportError: No module named PIL.

I have installed PIL successfully using

    pip install pil

and I&#39;ve also installed xcode command line tools. Nothing seem to work.

**Details**:

**Mac OS X 10.9**

**Python 2.7.6** 

python is /Library/Frameworks/Python.framework/Versions/2.7/bin/python

python is /usr/bin/python

python is /usr/local/bin/python

**Name: PIL**

Version: 1.1.7

Location: /usr/local/lib/python2.7/site-packages/PIL

ImportError: No module named Image

I have also tried
<pre><code class="hljs language-javascript">from PIL import Image
</code></pre>
but it gives me ImportError: No module named PIL.
I have installed PIL successfully using
<pre><code class="hljs">pip install pil
</code></pre>
and I've also installed xcode command line tools. Nothing seem to work.
Details:
Mac OS X 10.9
Python 2.7.6
python is /Library/Frameworks/Python.framework/Versions/2.7/bin/python
python is /usr/bin/python
python is /usr/local/bin/python
Name: PIL
Version: 1.1.7
Location: /usr/local/lib/python2.7/site-packages/PIL

I am getting TransactionManagementError when trying to save a Django User model instance and in its post_save signal, I&#39;m saving some models that have the user as the foreign key. 

The context and error is pretty similar to this question
https://stackoverflow.com/questions/20130507/django-transactionmanagementerror-when-using-signals

However, in this case, the error occurs **only while unit testing**.

It works well in manual testing, but unit tests fails.

Is there anything that I&#39;m missing?

**Here are the code snippets:**

views.py

    @csrf_exempt
    def mobileRegister(request):
        if request.method == &#39;GET&#39;:
            response = {&quot;error&quot;: &quot;GET request not accepted!!&quot;}
            return HttpResponse(json.dumps(response), content_type=&quot;application/json&quot;,status=500)
        elif request.method == &#39;POST&#39;:
            postdata = json.loads(request.body)
            try:
                # Get POST data which is to be used to save the user
                username = postdata.get(&#39;phone&#39;)
                password = postdata.get(&#39;password&#39;)
                email = postdata.get(&#39;email&#39;,&quot;&quot;)
                first_name = postdata.get(&#39;first_name&#39;,&quot;&quot;)
                last_name = postdata.get(&#39;last_name&#39;,&quot;&quot;)
                user = User(username=username, email=email,
                            first_name=first_name, last_name=last_name)
                user._company = postdata.get(&#39;company&#39;,None)
                user._country_code = postdata.get(&#39;country_code&#39;,&quot;+91&quot;)
                user.is_verified=True
                user._gcm_reg_id = postdata.get(&#39;reg_id&#39;,None)
                user._gcm_device_id = postdata.get(&#39;device_id&#39;,None)
                # Set Password for the user
                user.set_password(password)
                # Save the user
                user.save()


signal.py

    def create_user_profile(sender, instance, created, **kwargs):
        if created:
            company = None
            companycontact = None
            try:   # Try to make userprofile with company and country code provided
                user = User.objects.get(id=instance.id)
                rand_pass = random.randint(1000, 9999)
                company = Company.objects.get_or_create(name=instance._company,user=user)
                companycontact = CompanyContact.objects.get_or_create(contact_type=&quot;Owner&quot;,company=company,contact_number=instance.username)
                profile = UserProfile.objects.get_or_create(user=instance,phone=instance.username,verification_code=rand_pass,company=company,country_code=instance._country_code)
                gcmDevice = GCMDevice.objects.create(registration_id=instance._gcm_reg_id,device_id=instance._gcm_reg_id,user=instance)
            except Exception, e:
                pass

tests.py

    class AuthTestCase(TestCase):
        fixtures = [&#39;nextgencatalogs/fixtures.json&#39;]
        def setUp(self):
            self.user_data={
                &quot;phone&quot;:&quot;0000000000&quot;,
                &quot;password&quot;:&quot;123&quot;,
                &quot;first_name&quot;:&quot;Gaurav&quot;,
                &quot;last_name&quot;:&quot;Toshniwal&quot;
                }

        def test_registration_api_get(self):
            response = self.client.get(&quot;/mobileRegister/&quot;)
            self.assertEqual(response.status_code,500)

        def test_registration_api_post(self):
            response = self.client.post(path=&quot;/mobileRegister/&quot;,
                                        data=json.dumps(self.user_data),
                                        content_type=&quot;application/json&quot;)
            self.assertEqual(response.status_code,201)
            self.user_data[&#39;username&#39;]=self.user_data[&#39;phone&#39;]
            user = User.objects.get(username=self.user_data[&#39;username&#39;])
            # Check if the company was created
            company = Company.objects.get(user__username=self.user_data[&#39;phone&#39;])
            self.assertIsInstance(company,Company)
            # Check if the owner&#39;s contact is the same as the user&#39;s phone number
            company_contact = CompanyContact.objects.get(company=company,contact_type=&quot;owner&quot;)
            self.assertEqual(user.username,company_contact[0].contact_number)

Traceback:

    ======================================================================
    ERROR: test_registration_api_post (nextgencatalogs.apps.catalogsapp.tests.AuthTestCase)
    ----------------------------------------------------------------------
    Traceback (most recent call last):
      File &quot;/Users/gauravtoshniwal1989/Developer/Web/Server/ngc/nextgencatalogs/apps/catalogsapp/tests.py&quot;, line 29, in test_registration_api_post
        user = User.objects.get(username=self.user_data[&#39;username&#39;])
      File &quot;/Users/gauravtoshniwal1989/Developer/Web/Server/ngc/ngcvenv/lib/python2.7/site-packages/django/db/models/manager.py&quot;, line 151, in get
        return self.get_queryset().get(*args, **kwargs)
      File &quot;/Users/gauravtoshniwal1989/Developer/Web/Server/ngc/ngcvenv/lib/python2.7/site-packages/django/db/models/query.py&quot;, line 301, in get
        num = len(clone)
      File &quot;/Users/gauravtoshniwal1989/Developer/Web/Server/ngc/ngcvenv/lib/python2.7/site-packages/django/db/models/query.py&quot;, line 77, in __len__
        self._fetch_all()
      File &quot;/Users/gauravtoshniwal1989/Developer/Web/Server/ngc/ngcvenv/lib/python2.7/site-packages/django/db/models/query.py&quot;, line 854, in _fetch_all
        self._result_cache = list(self.iterator())
      File &quot;/Users/gauravtoshniwal1989/Developer/Web/Server/ngc/ngcvenv/lib/python2.7/site-packages/django/db/models/query.py&quot;, line 220, in iterator
        for row in compiler.results_iter():
      File &quot;/Users/gauravtoshniwal1989/Developer/Web/Server/ngc/ngcvenv/lib/python2.7/site-packages/django/db/models/sql/compiler.py&quot;, line 710, in results_iter
        for rows in self.execute_sql(MULTI):
      File &quot;/Users/gauravtoshniwal1989/Developer/Web/Server/ngc/ngcvenv/lib/python2.7/site-packages/django/db/models/sql/compiler.py&quot;, line 781, in execute_sql
        cursor.execute(sql, params)
      File &quot;/Users/gauravtoshniwal1989/Developer/Web/Server/ngc/ngcvenv/lib/python2.7/site-packages/django/db/backends/util.py&quot;, line 47, in execute
        self.db.validate_no_broken_transaction()
      File &quot;/Users/gauravtoshniwal1989/Developer/Web/Server/ngc/ngcvenv/lib/python2.7/site-packages/django/db/backends/__init__.py&quot;, line 365, in validate_no_broken_transaction
        &quot;An error occurred in the current transaction. You can&#39;t &quot;
    TransactionManagementError: An error occurred in the current transaction. You can&#39;t execute queries until the end of the &#39;atomic&#39; block.

    ----------------------------------------------------------------------

TransactionManagementError &quot;You can&#39;t execute queries until the end of the &#39;atomic&#39; block&quot; while using signals, but only during Unit Testing

Is there an explicit equivalent command in Python&#39;s matplotlib for Matlab&#39;s `hold on`? I&#39;m trying to plot all my graphs on the same axes. Some graphs are generated inside a `for` loop, and these are plotted separately from `su` and `sl`:

    import numpy as np
    import matplotlib.pyplot as plt

    for i in np.arange(1,5):
        z = 68 + 4 * np.random.randn(50)
        zm = np.cumsum(z) / range(1,len(z)+1)
        plt.plot(zm)
        plt.axis([0,50,60,80])

    plt.show()

    n = np.arange(1,51)
    su = 68 + 4 / np.sqrt(n)
    sl = 68 - 4 / np.sqrt(n)

    plt.plot(n,su,n,sl)

    plt.axis([0,50,60,80])
    plt.show()


Python equivalent to &#39;hold on&#39; in Matlab

I have seen a couple of posts on memory usage using Python Multiprocessing module. However the questions don&#39;t seem to answer the problem I have here. I am posting my analysis with the hope that some one can help me.
 
Issue
-----
I am using multiprocessing to perform tasks in parallel and I noticed that the memory consumption by the worker processes grow indefinitely. I have a small standalone example that should replicate what I notice.

    import multiprocessing as mp
    import time
    
    def calculate(num):
        l = [num*num for num in range(num)]
        s = sum(l)
        del l       # delete lists as an  option
        return s
        
    if __name__ == &quot;__main__&quot;:
        pool = mp.Pool(processes=2)
        time.sleep(5)
        print &quot;launching calculation&quot;
        num_tasks = 1000
        tasks =  [pool.apply_async(calculate,(i,)) for i in range(num_tasks)]
        for f in tasks:    
            print f.get(5)
        print &quot;calculation finished&quot;
        time.sleep(10)
        print &quot;closing  pool&quot;
        pool.close()
        print &quot;closed pool&quot;
        print &quot;joining pool&quot;
        pool.join()
        print &quot;joined pool&quot;
        time.sleep(5)

System
------
I am running Windows and I use the task manager to monitor the memory usage. I am running Python 2.7.6. 

Observation
-----------
I have summarized the memory consumption by the 2 worker processes below.

    +---------------+----------------------+----------------------+
    |  num_tasks    |  memory with del     | memory without del   |
    |               | proc_1   | proc_2    | proc_1   | proc_2    |
    +---------------+----------------------+----------------------+
    | 1000          | 4884     | 4694      | 4892     | 4952      |
    | 5000          | 5588     | 5596      | 6140     | 6268      |
    | 10000         | 6528     | 6580      | 6640     | 6644      |
    +---------------+----------------------+----------------------+

In the table above, I tried to change the number of tasks and observe the memory consumed at the end of all calculation and before `join`-ing the `pool`. The &#39;del&#39; and &#39;without del&#39; options are whether I un-comment or comment the `del l` line inside the `calculate(num)` function respectively. Before calculation, the memory consumption is around 4400.

1. It looks like manually clearing out the lists results in lower memory usage for the worker processes. I thought the garbage collector would have taken care of this. Is there a way to force garbage collection?
2. It is puzzling that with increase in number of tasks, the memory usage keeps growing in both cases. Is there a way to limit the memory usage?

I have a process that is based on this example, and is meant to run long term. I observe that this worker processes are hogging up lots of memory(~4GB) after an overnight run. Doing a `join` to release memory is not an option and I am trying to figure out a way without `join`-ing.

This seems a little mysterious. Has anyone encountered something similar? How can I fix this issue?

High Memory Usage Using Python Multiprocessing

Suppose I have the following code that plots something very simple using pandas:

    import pandas as pd
    values = [[1, 2], [2, 5]]
    df2 = pd.DataFrame(values, columns=[&#39;Type A&#39;, &#39;Type B&#39;], 
                       index=[&#39;Index 1&#39;, &#39;Index 2&#39;])
    df2.plot(lw=2, colormap=&#39;jet&#39;, marker=&#39;.&#39;, markersize=10, 
             title=&#39;Video streaming dropout by category&#39;)

![Output][1]


  [1]: http://i.stack.imgur.com/LIkH3.png

How do I easily set x and y-labels while preserving my ability to use specific colormaps? I noticed that the `plot()` wrapper for pandas DataFrames doesn&#39;t take any parameters specific for that.

Add x and y labels to a pandas plot

I want to run a Python script in Terminal, but I don&#39;t know how? I already have a saved file called gameover.py in the directory &quot;/User/luca/Documents/python&quot;.

How to run Python script on terminal?

I&#39;m trying to set my `$GOPATH` variable to run some example code on my machine:

    $ smitego-example go run main.go 
    main.go:5:2: cannot find package &quot;github.com/#GITHUB_USERNAME#/smitego&quot; in any of:
    	/usr/local/go/src/pkg/github.com/#GITHUB_USERNAME#/smitego (from $GOROOT)
    	($GOPATH not set)

    $ smitego-example export $GOPATH=$HOME
    -bash: export: `=/Users/#OSX_USERNAME#&#39;: not a valid identifier

![enter image description here][1]

Contents of `github.com/#GITHUB_USERNAME#/smitego/smitego.go`:

    package smitego
How can I set my `GOPATH` so it works always and forever?


  [1]: http://i.stack.imgur.com/muv49.png

Cannot set $GOPATH on Mac OSX

Given the following:

    - (void) someMethod
    {
        dispatch_async(dispatch_get_main_queue(), ^{
            myTimer = [NSTimer scheduledTimerWithTimeInterval: 60
                                                               target: self
                                                             selector: @selector(doSomething)
                                                             userInfo: nil
                                                              repeats: NO];
        });
    }

Where myTimer is declared in a private interface:

    @interface MyClass()
    {
        NSTimer * myTimer;
    }
    @end

How would one fix the following warning:
&lt;pre&gt;Block implicitly retains &#39;self&#39;; explicitly mention &#39;self&#39; to indicate this is intended behavior&lt;/pre&gt;

From what I have found so far, most suggestions involve putting something such as:

    - (void) someMethod
    {
        __typeof__(self) __weak wself = self;
        dispatch_async(dispatch_get_main_queue(), ^{
            wself.myTimer = [NSTimer scheduledTimerWithTimeInterval: 60
                                                               target: self
                                                             selector: @selector(doSomething)
                                                             userInfo: nil
                                                              repeats: NO];
        });
    }

Except, that myTimer is an ivar, meaning `wself` does not have access to any properties.

I guess my questions are:

1. Do/should I care?
2. Should I declare myTimer as a property?

I use ivars quite a bit through my code. I just added the `-Weverything` flag to my project to see if I can find any underlying issues and this is by far the most common warning. I have no problem going though and fixing it by making my ivars properties, but I want to make sure I get a better understanding before I do that.

Block implicitly retains &#39;self&#39;; explicitly mention &#39;self&#39; to indicate this is intended behavior

I am doing some Rails programming and I consistently see Homebrew referenced in solutions around the web but have never used it.

I also notice Homebrew in the terminal version 2.9 as an option next to &quot;Shell -&gt; New&quot; from the terminal drop down but when I select homebrew and issue commands, they fail. 

Usually with the &quot;command not found&quot; error.

Strangely enough I have been unable to locate a simple command to determine whether brew is installed or not.

How do I check to see if Homebrew is already installed on my Mac?

How to tell if homebrew is installed on Mac OS X

I am trying to resize some images, most of which are JPG. But in a few images, I am getting the error:

    Traceback (most recent call last):
      File &quot;image_operation_new.py&quot;, line 168, in modifyImage
        tempImage.save(finalName);
      File &quot;/Users/kshitiz/.virtualenvs/django_project/lib/python2.7/site-     packages/PIL/Image.py&quot;, line 1465, in save
       save_handler(self, fp, filename)
      File &quot;/Users/kshitiz/.virtualenvs/django_project/lib/python2.7/site-   packages/PIL/JpegImagePlugin.py&quot;, line 455, in _save
        raise IOError(&quot;cannot write mode %s as JPEG&quot; % im.mode)
    IOError: cannot write mode P as JPEG

I am not changing the image type and I&#39;m using the pillow library. My OS is Mac OS X. How can I resolve the issue?

Getting &quot;cannot write mode P as JPEG&quot; while operating on JPG image

I installed `Pillow`, and after I want to do:

    from PIL import Image

I get the following error:

    Traceback (most recent call last):
      File &quot;&lt;console&gt;&quot;, line 1, in &lt;module&gt;
      File &quot;/usr/local/lib/python2.7/dist-packages/PIL/Image.py&quot;, line 61, in &lt;module&gt;
    ImportError: cannot import name _imaging

However, if I import these separately, everything is fine, ie:

    import _imaging
    import Image

Do you know what the problem might be?


ImportError: cannot import name _imaging

I&#39;m making a simple API in Flask that accepts an image encoded in base64, then decodes it for further processing using Pillow.

I&#39;ve looked at some examples ([1][1], [2][2], [3][3]), and I think I get the gist of the process, but I keep getting an error where Pillow can&#39;t read the string I gave it.

Here&#39;s what I&#39;ve got so far:

    import cStringIO
    from PIL import Image
    import base64

    data = request.form
    image_string = cStringIO.StringIO(base64.b64decode(data[&#39;img&#39;]))
    image = Image.open(image_string)
    
which gives the error:

    IOError: cannot identify image file &lt;cStringIO.StringIO object at 0x10f84c7a0&gt;


  [1]: https://stackoverflow.com/questions/19908975/loading-base64-string-into-python-image-library
  [2]: https://stackoverflow.com/questions/3715493/encoding-an-image-file-with-base64
  [3]: https://stackoverflow.com/questions/19910845/strange-ioerror-when-opening-base64-string-in-pil


Decoding base64 from POST to use in PIL

I am trying to import all the images inside a directory (the directory location is known).  

    path = /home/user/mydirectory


I already know a way of finding out the length of the directory.
  
What I&#39;m not sure about is how I can import the images (using `PIL/Pillow`) into either a list or a dictionary, so they can be properly manipulated. 




Importing images from a directory (Python) to list or dictionary

The single line that I am trying to run is the following:

    from PIL import Image

However simple this may seem, it gives an error:

    Traceback (most recent call last):
      File &quot;C:\...\2014-10-22_12-49.py&quot;, line 1, in &lt;module&gt;
        from PIL import Image
      File &quot;C:\pyzo2014a\lib\site-packages\PIL\Image.py&quot;, line 29, in &lt;module&gt;
        from PIL import VERSION, PILLOW_VERSION, _plugins
    ImportError: cannot import name &#39;VERSION&#39;

In case that&#39;s helpful, I installed pillow from https://pypi.python.org/pypi/Pillow/2.6.1 (file `Pillow-2.6.1.win-amd64-py3.4.exe`) before running this (before that there was already som `PIL` install, which I uninstalled). The script is run in Pyzo with Python version 3.4.1.

What is going wrong, how can I import `Image`?

Content Type	Original Author	Original Content on Stackoverflow
Question	mihalios	View Question on Stackoverflow
Solution 1 - Python	Martijn Pieters	View Answer on Stackoverflow
Solution 2 - Python	qubodup	View Answer on Stackoverflow

ImportError: No module named Image

Python Problem Overview

Python Solutions

Solution 1 - Python

Solution 2 - Python

How do I write a complex multi-line if condition in Ruby?

Upgrading PHP on CentOS 6.5 (Final)

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