Unfortunately to be able to use the extension modules provided by others you&#39;ll be forced to use the official compiler to compile Python.  These are:

- Visual Studio 2008 for Python 2.7.
See: https://docs.python.org/2.7/using/windows.html#compiling-python-on-windows

- Visual Studio 2010 for Python 3.4.
See: https://docs.python.org/3.4/using/windows.html#compiling-python-on-windows

Alternatively, you can use MinGw to compile extensions in a way that won&#39;t depend on others.

See: https://docs.python.org/2/install/#gnu-c-cygwin-MinGW or https://docs.python.org/3.4/install/#gnu-c-cygwin-mingw

This allows you to have one compiler to build your extensions for both versions of Python, Python 2.x and Python 3.x.

For the different python versions:

    Visual C++ |CPython
    --------------------
    14.0       |3.5
    10.0       |3.3, 3.4
    9.0        |2.6, 2.7, 3.0, 3.1, 3.2

Source: [Windows Compilers for py](https://wiki.python.org/moin/WindowsCompilers)

Also refer: [this answer](https://stackoverflow.com/a/37631048/2142994)

[Visual Studio Community 2015](https://www.visualstudio.com/en-us/products/visual-studio-community-vs.aspx) suffices to build extensions for Python 3.5. It&#39;s free but a 6 GB download (overkill). On my computer it installed vcvarsall at  `C:\Program Files (x86)\Microsoft Visual Studio 14.0\VC\vcvarsall.bat`

For Python 3.4 you&#39;d need Visual Studio 2010. I don&#39;t think there&#39;s any free edition. See https://matthew-brett.github.io/pydagogue/python_msvc.html

When I go to debug my C++ project in Visual Studio, up pops a little warning dialogue box that tells me:

    A copy of datum.h was found in
    c:/users/brad/desktop/source/binary/datum.h, but the current
    source code is different from the version built into
    c:/users/brad/desktop/source/binary/datum.h.

I&#39;m having trouble understanding what this is even trying to tell me, let alone how to fix it. At first I thought it might be complaining that I&#39;d accidentally duplicated a file in the directory, which I checked, and found nothing of the sort, which leaves me pretty stumped. I also tried excluding the file from the solution and adding it again, which didn&#39;t fix the problem either.

The warning doesn&#39;t appear to actually hinder the development of my project, but I suppose warnings exist for a reason, so if anyone knows what&#39;s gone wrong, any advice would be greatly appreciated. To my knowledge, I didn&#39;t change anything to cause the message to appear, it just popped up one time I went to debug the solution and has kept on appearing ever since.

Also, more copies of the same warning have started popping up, pertaining to other header files in my solution (I haven&#39;t recieved any about .cpp files yet, but it could be a coincidence, because it&#39;s only been going on for about 20 minutes).

Visual Studio warning about copies of files with different contents

I have an enum defined like this:

    def enum(**enums):
        return type(&#39;Enum&#39;, (), enums)

    Status = enum(
           STATUS_OK=0,
           STATUS_ERR_NULL_POINTER=1, 
           STATUS_ERR_INVALID_PARAMETER=2)

I have a function that returns status as `Status` enum. 
How can I get the name of the enum value, and not just value?

    &gt;&gt;&gt; cur_status = get_Status()
    &gt;&gt;&gt; print(cur_status)
    1

I would like to get `STATUS_ERR_NULL_POINTER`, instead of `1`

How to get back name of the enum element?

I know that there is a [&quot;Microsoft Visual C++ Compiler for Python 2.7&quot;](http://www.microsoft.com/en-gb/download/details.aspx?id=44266) but is there, currently or planned, a Microsoft Visual C++ Compiler for Python 3.4 or eve Microsoft Visual C++ Compiler for Python 3.x for that matter?  It would be supremely beneficial if I didn&#39;t have to install a different version of visual studio on my entire lab.

Microsoft Visual C++ Compiler for Python 3.4

<p>I know that there is a <a href="http://www.microsoft.com/en-gb/download/details.aspx?id=44266" target="_blank" rel="noopener noreferrer">"Microsoft Visual C++ Compiler for Python 2.7"</a> but is there, currently or planned, a Microsoft Visual C++ Compiler for Python 3.4 or eve Microsoft Visual C++ Compiler for Python 3.x for that matter?  It would be supremely beneficial if I didn't have to install a different version of visual studio on my entire lab.</p>


I have the following code in `Python`:

    from selenium.webdriver import Firefox
    from contextlib import closing
    
    with closing(Firefox()) as browser:
      browser.get(url)

I would like to print the user-agent HTTP header and
possibly change it. Is it possible?



Change user-agent for Selenium web-driver

What I was trying to achieve, was something like this:

    &gt;&gt;&gt; camel_case_split(&quot;CamelCaseXYZ&quot;)
    [&#39;Camel&#39;, &#39;Case&#39;, &#39;XYZ&#39;]
    &gt;&gt;&gt; camel_case_split(&quot;XYZCamelCase&quot;)
    [&#39;XYZ&#39;, &#39;Camel&#39;, &#39;Case&#39;]

So I searched and found this [perfect regular expression][1]:

    (?&lt;=[a-z])(?=[A-Z])|(?&lt;=[A-Z])(?=[A-Z][a-z])

As the next logical step I tried:

    &gt;&gt;&gt; re.split(&quot;(?&lt;=[a-z])(?=[A-Z])|(?&lt;=[A-Z])(?=[A-Z][a-z])&quot;, &quot;CamelCaseXYZ&quot;)
    [&#39;CamelCaseXYZ&#39;]

Why does this not work, and how do I achieve the result from the linked question in python?

[1]: https://stackoverflow.com/a/7599674/1654255

**Edit: Solution summary**

I tested all provided solutions with a few test cases:

```none
string:					&#39;&#39;
AplusKminus:			[&#39;&#39;]
casimir_et_hippolyte:	[]
two_hundred_success:	[]
kalefranz:				string index out of range # with modification: either [] or [&#39;&#39;]

string:					&#39; &#39;
AplusKminus:     		[&#39; &#39;]
casimir_et_hippolyte:	[]
two_hundred_success:	[&#39; &#39;]
kalefranz:				[&#39; &#39;]

string:					&#39;lower&#39;
all algorithms:			[&#39;lower&#39;]

string:					&#39;UPPER&#39;
all algorithms:			[&#39;UPPER&#39;]

string:					&#39;Initial&#39;
all algorithms:			[&#39;Initial&#39;]

string:					&#39;dromedaryCase&#39;
AplusKminus:    		[&#39;dromedary&#39;, &#39;Case&#39;]
casimir_et_hippolyte:	[&#39;dromedary&#39;, &#39;Case&#39;]
two_hundred_success:	[&#39;dromedary&#39;, &#39;Case&#39;]
kalefranz:				[&#39;Dromedary&#39;, &#39;Case&#39;] # with modification: [&#39;dromedary&#39;, &#39;Case&#39;]

string:					&#39;CamelCase&#39;
all algorithms:			[&#39;Camel&#39;, &#39;Case&#39;]

string:					&#39;ABCWordDEF&#39;
AplusKminus:		    [&#39;ABC&#39;, &#39;Word&#39;, &#39;DEF&#39;]
casimir_et_hippolyte:	[&#39;ABC&#39;, &#39;Word&#39;, &#39;DEF&#39;]
two_hundred_success:	[&#39;ABC&#39;, &#39;Word&#39;, &#39;DEF&#39;]
kalefranz:				[&#39;ABCWord&#39;, &#39;DEF&#39;]
```

In summary you could say the solution by @kalefranz does not match the question (see the last case) and the solution by @casimir et hippolyte eats a single space, and thereby violates the idea that a split should not change the individual parts. The only difference among the remaining two alternatives is that my solution returns a list with the empty string on an empty string input and the solution by @200_success returns an empty list.
I don&#39;t know how the python community stands on that issue, so I say: I am fine with either one. And since 200_success&#39;s solution is simpler, I accepted it as the correct answer.

[2]: https://docs.python.org/3/library/abc.html

How to do CamelCase split in python

I have a DataFrame like this one:

    In [7]:
    frame.head()
    Out[7]:
    Communications and Search	Business	General	Lifestyle
    0	0.745763	0.050847	0.118644	0.084746
    0	0.333333	0.000000	0.583333	0.083333
    0	0.617021	0.042553	0.297872	0.042553
    0	0.435897	0.000000	0.410256	0.153846
    0	0.358974	0.076923	0.410256	0.153846

In here, I want to ask how to get column name which has maximum value for each row, the desired output is like this:

    In [7]:
        frame.head()
        Out[7]:
        Communications and Search	Business	General	Lifestyle   Max
        0	0.745763	0.050847	0.118644	0.084746           Communications 
        0	0.333333	0.000000	0.583333	0.083333           Business	 
        0	0.617021	0.042553	0.297872	0.042553           Communications 
        0	0.435897	0.000000	0.410256	0.153846           Communications 
        0	0.358974	0.076923	0.410256	0.153846           Business	

Find the column name which has the maximum value for each row

Looking for some help with integrating a JSON API call into a Python program.

I am looking to integrate the following API into a Python .py program to allow it to be called and the response to be printed.

The API guidance states that a bearer token must be generated to allow calls to the API, which I have done successfully. However I am unsure of the syntax to include this token as bearer token authentication in Python API request.

I can successfully complete the above request using cURL with a token included. I have tried &quot;urllib&quot; and &quot;requests&quot;  routes but to no avail.

Full API details: [IBM X-Force Exchange API Documentation - IP Reputation](https://api.xforce.ibmcloud.com/doc/#resource_IP_Reputation)

Making an API call in Python with an API that requires a bearer token

I have a pandas data frame like df with a column construct_name

    construct_name
    aaaa_t1_2    
    cccc_t4_10
    bbbb_g3_3

and so on. I want to first split all the names at the underscore and store the first element (aaaa,cccc, etc.) as another column name.

**Expected output**

    construct_name  name
    aaaa_t1_2       aaaa
    cccc_t4_10      bbbb

and so on.

I tried the following
`df[&#39;construct_name&#39;].map(lambda row:row.split(&quot;_&quot;))` and it gives me a list like

    [aaaa,t1,2]
    [cccc,t4,10]

 and so on

But when I do 

`df[&#39;construct_name&#39;].map(lambda row:row.split(&quot;_&quot;))[0]` to get the first element of the list I get an error. Can you suggest a fix. Thanks

splitting at underscore in python and storing the first value

In the MinGW-W64 online installer there are several fields you can select.  However I cannot find any documentation on this, and the guesses I&#39;ve made don&#39;t give me the behaviour I want.

Clearly a lot of work has gone into this project so it seems a pity that uptake is being held back by lack of basic documentation. 

The &quot;Version&quot; and &quot;Architecture&quot; fields are self-explanatory but the other fields I have trouble with are (values shown as of current installer):

  * **Threads**, options `posix` and `win32`
  * **Exception**, options `dwarf` and `sjlj`
  * **Build revision**, options `0`, `1`, `2`.

The values I chose on my previous install were `win32`, `seh` and `1` (clearly the options have changed since then but I am none the wiser as to what&#39;s what).

What are the pros and cons of each option, especially the threading model and exception handling, and which version is &quot;best&quot;?

The specific problems I have encountered using `x86_64-win32-seh-rev1` are:

  * `std::thread` and `std::condition_variable` are not supported
  * When debugging (using Code::Blocks as IDE), if an exception is thrown it does not jump to the exception handler; selecting Next Line does nothing 3 times and then aborts the run.

I can cope with the debugging problem but it would be really nice to have working C++11 threads.


Meaning of options in mingw-w64 installer

I have globally installed two npm packages [&quot;download&quot;](https://www.npmjs.com/package/download) and [&quot;enigmavirtualbox&quot;](https://www.npmjs.com/package/enigmavirtualbox) via command line:

`npm install -g download` and
`npm install -g engimavirtualbox`

I&#39;m trying to use them in a batch file to bundle a single .exe file from my node project. For both, the commands `npm list -g &lt;packagename&gt;` yield the respective version output, independent of the present working directory.

However, inside my batch script the commands &quot;download&quot; and &quot;enigmavirtualbox&quot; cannot be found.

Running `npm root -g` yields `C:\Users\&lt;username&gt;\AppData\Roaming\npm\node_modules` and looking inside that folder I can see that folders for both packages are present.

What I have tried:

- Changing `npm root` as described [here](http://blog.webbb.be/command-not-found-node-npm/)
- Uninstall and reinstall packages
- Add env. variable NODE_PATH to point to `C:\Users\&lt;username&gt;\AppData\Roaming\npm\node_modules`
- Add `C:\Users\&lt;username&gt;\AppData\Roaming\npm\node_modules` to PATH env. variable

The same setup works on my second computer (both run Win7 64bit). Is something wrong with my node installation, or what am I doing wrong?

Global NPM package installed but command not found

The Windows operating system can be either 32 bit or 64 bit. The **64 bit** version is called **Windows x64** but the **32 bit** version is called **Windows x86**. Why isn&#39;t it called **Windows x32**? What is the reason?

Why is Windows 32-bit called Windows x86 and not Windows x32?

On a windows machine I get this error

&gt; &#39;touch&#39; is not recognized as an internal or external command, operable program or batch file.

I was following these [instructions][1] which seem to be linux specific, but on a standard windows commandline it does not work like this:

    touch index.html app.js style.css

Is there a windows equivalent of the &#39;touch&#39; command from the linux / mac os / unix world ? Do I need to create these files by hand (and modify them to change the timestamp) in order to implement this sort of command? I am working with node and that doesn&#39;t seem very ... node-ish...

  [1]: https://makerlog.org/posts/leaflet-basics

Create an empty file on the commandline in windows (like the linux touch command)

I want my .bat script (test.bat) to create a shortcut to itself so that I can copy it to my windows 8 Startup folder. 

I have written this line of code to copy the file but I haven&#39;t yet found a way to create the said shortcut, as you can see it only copies the script.
 
    xcopy &quot;C:\Users\Gabriel\Desktop\test.bat&quot; &quot;C:\Users\Gabriel\AppData\Roaming\Microsoft\Windows\Start Menu\Programs\Startup&quot;

Can you help me out?

How do I create a shortcut via command-line in Windows?


It is my understanding that the `range()` function, which is actually [an object type in Python 3][1], generates its contents on the fly, similar to a generator.

This being the case, I would have expected the following line to take an inordinate amount of time because, in order to determine whether 1 quadrillion is in the range, a quadrillion values would have to be generated:

    1_000_000_000_000_000 in range(1_000_000_000_000_001)

Furthermore: it seems that no matter how many zeroes I add on, the calculation more or less takes the same amount of time (basically instantaneous).

I have also tried things like this, but the calculation is still almost instant:

    # count by tens
    1_000_000_000_000_000_000_000 in range(0,1_000_000_000_000_000_000_001,10)

If I try to implement my own range function, the result is not so nice!

    def my_crappy_range(N):
        i = 0
        while i &lt; N:
            yield i
            i += 1
        return

What is the `range()` object doing under the hood that makes it so fast?

----------

[Martijn Pieters&#39;s answer][2] was chosen for its completeness, but also see [abarnert&#39;s first answer][3] for a good discussion of what it means for `range` to be a full-fledged *sequence* in Python 3, and some information/warning regarding potential inconsistency for `__contains__` function optimization across Python implementations. [abarnert&#39;s other answer][4] goes into some more detail and provides links for those interested in the history behind the optimization in Python 3 (and lack of optimization of `xrange` in Python 2). Answers [by poke][5] and [by wim][6] provide the relevant C source code and explanations for those who are interested. 

  [1]: https://docs.python.org/3/library/stdtypes.html#typesseq-range
  [2]: https://stackoverflow.com/a/30081318/2437514
  [3]: https://stackoverflow.com/a/30081894/2437514
  [4]: https://stackoverflow.com/a/30088140/2437514
  [5]: https://stackoverflow.com/a/30081467/2437514
  [6]: https://stackoverflow.com/a/30081470/2437514

Why is &quot;1000000000000000 in range(1000000000000001)&quot; so fast in Python 3?

I am trying to use connect to another party using Python 3 asyncio module and get this error:

         36     sslcontext = ssl.SSLContext(ssl.PROTOCOL_TLSv1)
    ---&gt; 37     sslcontext.load_cert_chain(cert, keyfile=ca_cert)
         38
    
    SSLError: [SSL] PEM lib (_ssl.c:2532)

The question is just what the error mean. My certificate is correct, _the keyfile (CA certificate) might not_.

What does &quot;SSLError: [SSL] PEM lib (_ssl.c:2532)&quot; mean using the Python ssl library?

I have been using Spyder installed with with Anaconda distribution which uses Python 2.7 as default. Currently I need to set up a development virtual environment with Python 3.4. 

Top two suggestions after research online are:

 1.  to set up virtual environment first and to point change the preferences of Spyder , e.g [here][1]; 
 2.  to install all Spyder dependencies, like PyQt4, in the virtual environment itself, e. g. [here][2] ;

Both recommendations are cumbersome and do not look like smart options for development.

Is there a solution that would allow to run Spyder with required Python version automatically after activating the required virtual environment?


  [1]: https://stackoverflow.com/questions/28190500/virtualenv-ipython-in-spyder-not-working
  [2]: https://stackoverflow.com/q/28190500/3052217

How to run Spyder in virtual environment?

I am trying to horizontally combine some JPEG images in Python.

## Problem
I have 3 images - each is 148 x 95 - see attached. I just made 3 copies of the same image - that is why they are the same.

![enter image description here][1]![enter image description here][2]![enter image description here][3]

## My attempt
I am trying to horizontally join them using the following code:

    import sys
    from PIL import Image
    
    list_im = [&#39;Test1.jpg&#39;,&#39;Test2.jpg&#39;,&#39;Test3.jpg&#39;]
    
    # creates a new empty image, RGB mode, and size 444 by 95
    new_im = Image.new(&#39;RGB&#39;, (444,95))

    for elem in list_im:
        for i in xrange(0,444,95):
            im=Image.open(elem)
            new_im.paste(im, (i,0))
    new_im.save(&#39;test.jpg&#39;)

However, this is producing the output attached as `test.jpg`.

![enter image description here][4]

## Question
Is there a way to horizontally concatenate these images such that the sub-images in test.jpg do not have an extra partial image showing?

### Additional Information
I am looking for a way to horizontally concatenate n images. I would like to use this code generally so I would prefer to:

 - not to hard-code image dimensions, if possible
 - specify dimensions in one line so that they can be easily changed

  [1]: http://i.stack.imgur.com/KVMyX.jpg
  [2]: http://i.stack.imgur.com/hlGpu.jpg
  [3]: http://i.stack.imgur.com/MgAyo.jpg
  [4]: http://i.stack.imgur.com/69hcL.jpg

Combine several images horizontally with Python

I was wondering why list comprehension is so much faster than appending to a list. I thought the difference is just expressive, but it&#39;s not.

    &gt;&gt;&gt; import timeit 
    &gt;&gt;&gt; timeit.timeit(stmt=&#39;&#39;&#39;\
    t = []
    for i in range(10000):
    	t.append(i)&#39;&#39;&#39;, number=10000)
    9.467898777974142
    
    &gt;&gt;&gt; timeit.timeit(stmt=&#39;t= [i for i in range(10000)]&#39;, number=10000)
    4.1138417314859

The list comprehension is 50% faster. Why?

Why is a list comprehension so much faster than appending to a list?

New Go programmers often don&#39;t know or get confused what the fundamental go build command does.

What do exactly the `go build` and `go install` commands build and where do they put the result/output?

What does go build build? (go build vs. go install)

**Question 1:**

Why does the following code compile without having a return statement?
		
	public int a() {
		while(true);
	}

Notice: If I add return after the while then I get an `Unreachable Code Error`.

**Question 2:** 

On the other hand, why does the following code compile,

	public int a() {
		while(0 == 0);
	}

even though the following does not.

	public int a(int b) {
		while(b == b);
	}

Java method with return type compiles without return statement

The &quot;Compile on save&quot; feature isn&#39;t working for me after upgrading to Visual Studio 2015.  When I make a change to a `.ts` file in my project and save, the status bar at the bottom of the IDE says `Output(s) generated successfully`, but the generated `.js` file doesn&#39;t change.

Here&#39;s what I&#39;ve tried:

- adding the following to the root `&lt;Project&gt;` element in my `.csproj`:

        &lt;PropertyGroup&gt;
            &lt;TypeScriptCompileOnSaveEnabled&gt;True&lt;/TypeScriptCompileOnSaveEnabled&gt;
        &lt;/PropertyGroup&gt;


- checking and unchecking the &quot;Automatically compile TypeScript files which are not part of a project&quot; option in `Tools -&gt; Options -&gt; TypeScript -&gt; Project`:

 [![enter image description here][1]][1]

- double checking to make sure &quot;Compile on save&quot; is checked in my project&#39;s TypeScript Build properties:

 [![enter image description here][2]][2]

What am I missing?

As a side note, the TypeScript compilation step does work as expected when triggered by a regular build.

  [1]: http://i.stack.imgur.com/j6QCM.png
  [2]: http://i.stack.imgur.com/QSWMo.png

TypeScript &quot;Compile on save&quot; feature not working in Visual Studio 2015

I&#39;m trying to compile miniSAT on Kali Linux 64 bits but I keep getting the error message:

&gt; fatal error: zlib.h: no such file or directory

I have read that there might be a linking problem that makes the compiler unable to find the header files, but I&#39;m new to Linux and do not know how to solve that.

How to fix fatal error: zlib.h: no such file or directory?

I am researching CoffeeScript on the website [http://coffeescript.org/](http://coffeescript.org/), and it has the text

&gt; The CoffeeScript compiler is itself written in CoffeeScript

How can a compiler compile itself, or what does this statement mean?

Content Type	Original Author	Original Content on Stackoverflow
Question	Rusty Weber	View Question on Stackoverflow
Solution 1 - Python	Vivian De Smedt	View Answer on Stackoverflow
Solution 2 - Python	Ani Menon	View Answer on Stackoverflow
Solution 3 - Python	Colonel Panic	View Answer on Stackoverflow

Microsoft Visual C++ Compiler for Python 3.4

Python Problem Overview

Python Solutions

Solution 1 - Python

Solution 2 - Python

Solution 3 - Python

How to get back name of the enum element?

Visual Studio warning about copies of files with different contents

Attributions