When doing;

    a_file = open(&#39;E:\Python Win7-64-AMD 3.3\Test&#39;, encoding=&#39;utf-8&#39;)

...you&#39;re trying to open a _directory_ as a file, which may (and on most non UNIX file systems will) fail.

Your other example though;

    a_file = open(&#39;E:\Python Win7-64-AMD 3.3\Test\a.txt&#39;, encoding=&#39;utf-8&#39;)

should work well if you just have the permission on `a.txt`. You may want to use a raw (`r`-prefixed) string though, to make sure your path does not contain any escape characters like `\n` that will be translated to special characters.

    a_file = open(r&#39;E:\Python Win7-64-AMD 3.3\Test\a.txt&#39;, encoding=&#39;utf-8&#39;)



For me, I was writing to a file that is opened in Excel.

For me, I got this error when I was trying to write a file to a folder and wanted to make sure the folder existed. I accidentally used:
```python
path = Path(&quot;path/to/my/file.txt&quot;)
path.mkdir(parents=True, exist_ok=True)
with open(path, &quot;w&quot;) as file:
    ...
```
but the second line means &quot;make a *directory* at *this* exact path (and make its parents too, without throwing errors for them existing already)&quot;. The third line then throws a `PermissionError`, because you can&#39;t use `open()` on a *directory* path, of course! The second line should have been:
```python
path.parent.mkdir(parents=True, exist_ok=True)
```

I encountered this problem when I accidentally tried running my python module through the command prompt while my working directory was `C:\Windows\System32` instead of the usual directory from which I run my python module

When a user makes some changes (cropping, red-eye removal, ...) to photos in the built-in **Photos.app** on iOS, the changes are not applied to the `fullResolutionImage` returned by the corresponding `ALAssetRepresentation`. 

However, the changes are applied to the `thumbnail` and the `fullScreenImage` returned by the `ALAssetRepresentation`.
Furthermore, information about the applied changes can be found in the `ALAssetRepresentation`&#39;s   metadata dictionary via the key `@&quot;AdjustmentXMP&quot;`.

I would like to apply these changes to the `fullResolutionImage` myself to preserve consistency. I&#39;ve found out that on **iOS6+** `CIFilter`&#39;s `filterArrayFromSerializedXMP:                              inputImageExtent:error:` can convert this XMP-metadata to an array of `CIFilter`&#39;s:

    ALAssetRepresentation *rep; 
    NSString *xmpString = rep.metadata[@&quot;AdjustmentXMP&quot;];
    NSData *xmpData = [xmpString dataUsingEncoding:NSUTF8StringEncoding];
            
    CIImage *image = [CIImage imageWithCGImage:rep.fullResolutionImage];
            
    NSError *error = nil;
    NSArray *filterArray = [CIFilter filterArrayFromSerializedXMP:xmpData 
                                                 inputImageExtent:image.extent 
                                                            error:&amp;error];
    if (error) {
         NSLog(@&quot;Error during CIFilter creation: %@&quot;, [error localizedDescription]);
    }

    CIContext *context = [CIContext contextWithOptions:nil];
                   
    for (CIFilter *filter in filterArray) {
         [filter setValue:image forKey:kCIInputImageKey];
         image = [filter outputImage];
    }



However, this works only for some filters (cropping, auto-enhance) but not for others like red-eye removal. In these cases, the `CIFilter`s have no visible effect. Therefore, my questions:

 - Is anyone aware of a way to create red-eye removal `CIFilter`? (In a way consistent with the Photos.app. The filter with the key `kCIImageAutoAdjustRedEye` is not enough. E.g., it does not take parameters for the position of the eyes.)
 - Is there a possibility to generate and apply these filters under iOS 5? 

 

Interpret XMP-Metadata in ALAssetRepresentation

What is the difference between `static const` and `const`?
For example:

    static const int a=5;
    const int i=5;

Is there any difference between them?
When would you use one over the other?

What is the difference between static const and const?

Just starting to learn some Python and I&#39;m having an issue as stated below:

```py
a_file = open(&#39;E:\Python Win7-64-AMD 3.3\Test&#39;, encoding=&#39;utf-8&#39;)

Traceback (most recent call last):
  File &quot;&lt;pyshell#9&gt;&quot;, line 1, in &lt;module&gt;
    a_file = open(&#39;E:\Python Win7-64-AMD 3.3\Test&#39;, encoding=&#39;utf-8&#39;)
PermissionError: [Errno 13] Permission denied: &#39;E:\\Python Win7-64-AMD 3.3\\Test\
```

Seems to be a file permission error, if any one can shine some light it would be greatly appreciated.

**NOTE: not sure how Python and Windows files work but I&#39;m logged in to Windows as Admin and the folder has admin permissions.**

I have tried changing `.exe` properties to run as Admin.

PermissionError: [Errno 13] in Python

Just starting to learn some Python and I'm having an issue as stated below:
<pre><code class="hljs language-ini">a_file = open('E:\Python Win7-64-AMD 3.3\Test', encoding='utf-8')

Traceback (most recent call last):
 File "&#x3C;pyshell#9>", line 1, in &#x3C;module>
 a_file = open('E:\Python Win7-64-AMD 3.3\Test', encoding='utf-8')
PermissionError: [Errno 13] Permission denied: 'E:\\Python Win7-64-AMD 3.3\\Test\
</code></pre>
Seems to be a file permission error, if any one can shine some light it would be greatly appreciated.
NOTE: not sure how Python and Windows files work but I'm logged in to Windows as Admin and the folder has admin permissions.
I have tried changing <code>.exe</code> properties to run as Admin.

I have a simple python script, that has some functions that run in a loop (I&#39;m taking sensor readings).

    while True:
        print &quot;Doing a function&quot;

If the keyboard is pressed I&#39;d like to print &quot;key pressed&quot;.

What&#39;s the simplest way of doing this in Python? I&#39;ve searched high and low. I&#39;ve found out how to do it with pygame, but I&#39;d rather do it without. If I do have to use pygame is it possible to not have a separate window for the application?:

    import pygame, time
    from pygame.locals import *
  
    pygame.init()
    screen = pygame.display.set_mode((640, 480))
    pygame.display.set_caption(&#39;Pygame Keyboard Test&#39;)
    pygame.mouse.set_visible(0)
  

    while True:

       print &quot;doing a function&quot;

        for event in pygame.event.get():
          if (event.type == KEYUP) or (event.type == KEYDOWN):
             print &quot;key pressed&quot;
             time.sleep(0.1)
  


What&#39;s the simplest way of detecting keyboard input in a script from the terminal?

What is the best way to split a string like `&quot;HELLO there HOW are YOU&quot;` by upper case words (in Python)? 

So I&#39;d end up with an array like such: `results = [&#39;HELLO there&#39;, &#39;HOW are&#39;, &#39;YOU&#39;]`

----
EDIT: 

I have tried: 

    p = re.compile(&quot;\b[A-Z]{2,}\b&quot;)
    print p.split(page_text)

It doesn&#39;t seem to work, though.

Split string based on regex

I am trying to find an app that can detect faces in my pictures, make the detected face centered and crop 720 x 720 pixels of the picture. It is rather very time consuming &amp; meticulous to edit around hundreds of pictures I plan to do that.

I have tried doing this using [python opencv mentioned here][1] but I think it is outdated. I&#39;ve also tried [using this][2] but it&#39;s also giving me an error in my system. Also tried using face detection plugin for GIMP but it is designed for GIMP 2.6 but I am using 2.8 on a regular basis. I also tried doing what was posted at ultrahigh blog but it is very outdated (since I&#39;m using a Precise derivative of Ubuntu, while the blogpost was made way back when it was still Hardy). Also tried using Phatch but there is no face detection so some cropped pictures have their face cut right off.

I have tried all of the above and wasted half a day trying to make any of the above do what I needed to do.

Do you guys have suggestion to achieve a goal to around 800 pictures I have.

My operating system is Linux Mint 13 MATE.

Note: I was going to add 2 more links but stackexchange prevented me to post two more links as I don&#39;t have much reputation yet.

  [1]: http://creatingwithcode.com/howto/face-detection-in-static-images-with-python/
  [2]: http://www.givp.org/blog/2011/06/13/image-cropping-and-face-detection/


Detect face then autocrop pictures

Is there a simple, built-in way to print a 2D Python list as a 2D matrix?

So this:

    [[&quot;A&quot;, &quot;B&quot;], [&quot;C&quot;, &quot;D&quot;]]

would become something like

    A    B
    C    D

I found the `pprint` module, but it doesn&#39;t seem to do what I want.

Pretty print 2D list?

Currently, I have some code like this

    import numpy as np
    ret = np.array([])
    for i in range(100000):
      tmp =  get_input(i)
      ret = np.append(ret, np.zeros(len(tmp)))
      ret = np.append(ret, np.ones(fixed_length))

I think this code is **not efficient** as `np.append` needs to return a copy of the array instead of **modify the ret in-place**

I was wondering whether I can use the `extend` for a numpy array like this:

    import numpy as np
    from somewhere import np_extend
    ret = np.array([])
    for i in range(100000):
      tmp =  get_input(i)
      np_extend(ret, np.zeros(len(tmp)))
      np_extend(ret, np.ones(fixed_length))

So that the `extend` would be much more efficient.
Does anyone have ideas about this?
Thanks!

How to extend an array in-place in Numpy?

How can I check if the elements of a list are of the same type, without checking individually every element if possible?

For example, I would like to have a function to check that every element of this list is an integer (which is clearly false):

    x = [1, 2.5, &#39;a&#39;]

    def checkIntegers(x):
        # return True if all elements are integers, False otherwise

Check if all elements of a list are of the same type

`filter`, `map`, and `reduce` work perfectly in Python 2. Here is an example:

    &gt;&gt;&gt; def f(x):
            return x % 2 != 0 and x % 3 != 0
    &gt;&gt;&gt; filter(f, range(2, 25))
    [5, 7, 11, 13, 17, 19, 23]

    &gt;&gt;&gt; def cube(x):
            return x*x*x
    &gt;&gt;&gt; map(cube, range(1, 11))
    [1, 8, 27, 64, 125, 216, 343, 512, 729, 1000]

    &gt;&gt;&gt; def add(x,y):
            return x+y
    &gt;&gt;&gt; reduce(add, range(1, 11))
    55

But in Python 3, I receive the following outputs:

    &gt;&gt;&gt; filter(f, range(2, 25))
    &lt;filter object at 0x0000000002C14908&gt;

    &gt;&gt;&gt; map(cube, range(1, 11))
    &lt;map object at 0x0000000002C82B70&gt;

    &gt;&gt;&gt; reduce(add, range(1, 11))
    Traceback (most recent call last):
      File &quot;&lt;pyshell#8&gt;&quot;, line 1, in &lt;module&gt;
        reduce(add, range(1, 11))
    NameError: name &#39;reduce&#39; is not defined

I would appreciate if someone could explain to me why this is.

Screenshot of code for further clarity:

[![IDLE sessions of Python 2 and 3 side-by-side](http://i.imgur.com/WekeD.png)](http://i.imgur.com/WekeD.png)

How to use filter, map, and reduce in Python 3

I got this error when run test.py


    C:\Python32&gt;python.exe test.py
    Traceback (most recent call last):
      File &quot;test.py&quot;, line 5, in &lt;module&gt;
        import httplib
    ImportError: No module named httplib

How to correct it?

Code block for **test.py**:

    #!/usr/local/bin/python
    
    import httplib
    import sys
    import re
    from HTMLParser import HTMLParser
    
    
    class miniHTMLParser( HTMLParser ):
    
      viewedQueue = []
      instQueue = []
    
      def get_next_link( self ):
        if self.instQueue == []:
          return &#39;&#39;
        else:
          return self.instQueue.pop(0)
    
    
      def gethtmlfile( self, site, page ):
        try:
          httpconn = httplib.HTTPConnection(site)
          httpconn.request(&quot;GET&quot;, page)
          resp = httpconn.getresponse()
          resppage = resp.read()
        except:
          resppage = &quot;&quot;
    
        return resppage
    
    
      def handle_starttag( self, tag, attrs ):
        if tag == &#39;a&#39;:
          newstr = str(attrs[0][1])
          if re.search(&#39;http&#39;, newstr) == None:
            if re.search(&#39;mailto&#39;, newstr) == None:
              if re.search(&#39;htm&#39;, newstr) != None:
                if (newstr in self.viewedQueue) == False:
                  print (&quot;  adding&quot;, newstr)
                  self.instQueue.append( newstr )
                  self.viewedQueue.append( newstr )
              else:
                print (&quot;  ignoring&quot;, newstr)
            else:
              print (&quot;  ignoring&quot;, newstr)
          else:
            print (&quot;  ignoring&quot;, newstr)
    
    
    def main():
    
      if sys.argv[1] == &#39;&#39;:
        print (&quot;usage is ./minispider.py site link&quot;)
        sys.exit(2)
    
      mySpider = miniHTMLParser()
    
      link = sys.argv[2]
    
      while link != &#39;&#39;:
    
        print (&quot;\nChecking link &quot;, link)
    
        # Get the file from the site and link
        retfile = mySpider.gethtmlfile( sys.argv[1], link )
    
        # Feed the file into the HTML parser
        mySpider.feed(retfile)
    
        # Search the retfile here
    
        # Get the next link in level traversal order
        link = mySpider.get_next_link()
    
      mySpider.close()
    
      print (&quot;\ndone\n&quot;)
    
    if __name__ == &quot;__main__&quot;:
      main()


import httplib ImportError: No module named httplib

I&#39;ve been trying to find out how to represent a maximum integer, and I&#39;ve read to use `&quot;sys.maxint&quot;`. However, in Python 3 when I call it I get:

    AttributeError: module &#39;object&#39; has no attribute &#39;maxint&#39;


What is sys.maxint in Python 3?

How can I split a byte string into a list of lines?

In python 2 I had:

    rest = &quot;some\nlines&quot;
    for line in rest.split(&quot;\n&quot;):
        print line

The code above is simplified for the sake of brevity, but now after some regex processing, I have a byte array in `rest` and I need to iterate the lines.

Content Type	Original Author	Original Content on Stackoverflow
Question	BenniMcBeno	View Question on Stackoverflow
Solution 1 - Python	Joachim Isaksson	View Answer on Stackoverflow
Solution 2 - Python	Kai Wang	View Answer on Stackoverflow
Solution 3 - Python	Mew	View Answer on Stackoverflow
Solution 4 - Python	Toldry	View Answer on Stackoverflow

PermissionError: [Errno 13] in Python

Python Problem Overview

Python Solutions

Solution 1 - Python

Solution 2 - Python

Solution 3 - Python

Solution 4 - Python

What is the difference between static const and const?

Interpret XMP-Metadata in ALAssetRepresentation

Attributions