    text = text.replace(&quot;very&quot;, &quot;not very&quot;, 1)

&lt;b&gt;&lt;/b&gt;

    &gt;&gt;&gt; help(str.replace)
    Help on method_descriptor:
    
    replace(...)
        S.replace (old, new[, count]) -&gt; string
        
        Return a copy of string S with all occurrences of substring
        old replaced by new.  If the optional argument count is
        given, only the first count occurrences are replaced.



    text = text.replace(&quot;very&quot;, &quot;not very&quot;, 1)

The third parameter is the maximum number of occurrences that you want to replace.  
From [the documentation for Python][1]:

&gt; **string.replace(s, old, new[, maxreplace])**  
Return a copy of string s with all occurrences of substring old replaced by new. If the optional argument maxreplace is given, the first maxreplace occurrences are replaced.


  [1]: https://docs.python.org/2/library/string.html

From http://docs.python.org/release/2.5.2/lib/string-methods.html :

&gt; **replace( old, new[, count])**  
&gt;     Return a copy of the string with all occurrences of substring old replaced by new. If the optional argument count is given, only the
&gt; first count occurrences are replaced.

I didn&#39;t try but I believe it works

How to sort the files according to the time stamp in unix?
I need to sort the files and also based on time they created.

How to sort the files according to the time stamp in unix?

In Python 3, I want to create a list that will contain the last 5 variables entered into it.

Here is an example:

    &gt;&gt;&gt;l = []
    &gt;&gt;&gt;l.append(&#39;apple&#39;)
    &gt;&gt;&gt;l.append(&#39;orange&#39;)
    &gt;&gt;&gt;l.append(&#39;grape&#39;)
    &gt;&gt;&gt;l.append(&#39;banana&#39;)
    &gt;&gt;&gt;l.append(&#39;mango&#39;)
    &gt;&gt;&gt;print(l)
    [&#39;apple&#39;,&#39;orange&#39;,&#39;grape&#39;,&#39;banana&#39;,&#39;mango&#39;]
    &gt;&gt;&gt;l.append(&#39;kiwi&#39;)
    &gt;&gt;&gt;print(l)
    [&#39;orange&#39;,&#39;grape&#39;,&#39;banana&#39;,&#39;mango&#39;,&#39;kiwi&#39;] #only 5 items in list

So, in python, is there any way to achieve what is demonstrated above? The variable does not need to be a list, I just used it as an example.

How to force a list to a fixed size?

I have something like this:

    text = &#39;This text is very very long.&#39;
    replace_words = [&#39;very&#39;,&#39;word&#39;]
   
    for word in replace_words:
        text = text.replace(&#39;very&#39;,&#39;not very&#39;)



I would like to only replace the first &#39;very&#39; or choose which &#39;very&#39; gets overwritten. I&#39;m doing this on much larger amounts of text so I want to control how duplicate words are being replaced.

Replace first occurrence only of a string?

I have something like this:
<pre><code class="hljs language-ini">text = 'This text is very very long.'
replace_words = ['very','word']

for word in replace_words:
 text = text.replace('very','not very')
</code></pre>
I would like to only replace the first 'very' or choose which 'very' gets overwritten. I'm doing this on much larger amounts of text so I want to control how duplicate words are being replaced.

I&#39;am tasked with converting tons of .doc files to .pdf. And the only way my supervisor wants me to do this is through MSWord 2010. I know I should be able to automate this with python COM automation. Only problem is I dont know how and where to start. I tried searching for some tutorials but was not able to find any (May be I might have, but I don&#39;t know what I&#39;m looking for). 

Right now I&#39;m reading through [this][1]. Dont know how useful this is going to be.


  [1]: http://oreilly.com/catalog/pythonwin32/chapter/ch12.html#49339

.doc to pdf using python

I have a Mac running Python 2.6. When I try to use `easy_install` I get this message:

    /usr/bin/easy_install-2.6:7: UserWarning: Module pkg_resources was already imported from /System/Library/Frameworks/Python.framework/Versions/2.6/Extras/lib/python/pkg_resources.pyc, but /Library/Python/2.6/site-packages is being added to sys.path
      from pkg_resources import load_entry_point
    /usr/bin/easy_install-2.6:7: UserWarning: Module site was already imported from /System/Library/Frameworks/Python.framework/Versions/2.6/lib/python2.6/site.pyc, but /Library/Python/2.6/site-packages is being added to sys.path
      from pkg_resources import load_entry_point
    Traceback (most recent call last):
      File &quot;/usr/bin/easy_install-2.6&quot;, line 10, in &lt;module&gt;
        load_entry_point(&#39;setuptools==0.6c9&#39;, &#39;console_scripts&#39;, &#39;easy_install&#39;)()
      File &quot;/System/Library/Frameworks/Python.framework/Versions/2.6/Extras/lib/python/pkg_resources.py&quot;, line 271, in load_entry_point
        return False
      File &quot;/System/Library/Frameworks/Python.framework/Versions/2.6/Extras/lib/python/pkg_resources.py&quot;, line 2173, in load_entry_point
        deps = []
    ImportError: Entry point (&#39;console_scripts&#39;, &#39;easy_install&#39;) not found

I am very confused by this and I want to know how I can fix this. Previously I didn&#39;t get this message, then after installing `pip` and uninstalling it, easy_install no longer works. I was wondering how I could fix this, or restore the default Python or easy_install setting on Mac.


Why is Python easy_install not working on my Mac?

I need to insert rows into PG one of the fields is date and time with time stamp, this is the time of incident, so I can not use --&gt; current_timestamp function of Postgres at the time of insertion, so how can I then insert the time and date which I collected before into pg row in the same format as it would have been created by current_timestamp at that point in time.


How to insert current_timestamp into Postgres via python

How can I access captured groups if I do `findall(r&#39;regex(with)capturing.goes.here&#39;)` ?
I know I can do it through `finditer`, but I don&#39;t want to iterate.

Capturing group with findall?

I am new to Python (usually work on C#), started using it over the last couple of days.

Within a class, do you need to prefix any call to that classes data members and methods?  So, if I am calling a method or obtaining a value from that class, from within that class, I need to use `self.method()` or `self.intvalue`, for example?

I just want to check that there isn&#39;t a less verbose way that I have not encountered yet.

Python &#39;self&#39; keyword

I wanted to ask about a specific point made in Effective C++. 

It says:

&gt; A destructor should be made virtual if a class needs to act like a polymorphic class. It further adds that since `std::string` does not have a virtual destructor, one should never derive from it. Also `std::string` is not even designed to be a base class, forget polymorphic base class. 

I do not understand what specifically is required in a class to be eligible for being a base class (not a polymorphic one)?

Is the only reason that I should not derive from `std::string` class is it does not have a virtual destructor? For reusability purpose a base class can be defined and multiple derived class can inherit from it. So what makes `std::string` not even eligible as a base class?

Also, if there is a base class purely defined for reusability purpose and there are many derived types, is there any way to prevent client from doing `Base* p = new Derived()` because the classes are not meant to be used polymorphically?

Why should one not derive from c++ std string class?

I need to get the last part of current directory, for example  from `/Users/smcho/filegen_from_directory/AIRPassthrough`, I need to get `AIRPassthrough`. 

With python, I can get it with this code.

    import os.path
    
    path = &quot;/Users/smcho/filegen_from_directory/AIRPassthrough&quot;
    print os.path.split(path)[-1]

Or

    print os.path.basename(path)

How can I do the same thing with C#?

## ADDED
With the help from the answerers, I found what I needed.

    using System.Linq;
    string fullPath = Path.GetFullPath(fullPath).TrimEnd(Path.DirectorySeparatorChar);
    string projectName  = fullPath.Split(Path.DirectorySeparatorChar).Last();

or 

    string fullPath = Path.GetFullPath(fullPath).TrimEnd(Path.DirectorySeparatorChar);
    string projectName = Path.GetFileName(fullPath);

Get the (last part of) current directory name in C#

I am using R to parse a list of strings in the form:

    original_string &lt;- &quot;variable_name=variable_value&quot;

First, I extract the variable name and value from the original string and convert the value to numeric class. 

    parameter_value &lt;- as.numeric(&quot;variable_value&quot;)
    parameter_name &lt;- &quot;variable_name&quot;
    
Then, I would like to assign the value to a variable with the same name as the `parameter_name` string.

    variable_name &lt;- parameter_value

What is/are the function(s) for doing this?

Convert string to a variable name

Does anyone know of a regular expression I could use to find URLs within a string? I&#39;ve found a lot of regular expressions on Google for determining if an entire string is a URL but I need to be able to search an entire string for URLs.  For example, I would like to be able to find `www.google.com` and `http://yahoo.com` in the following string:

&lt;!-- Language: none --&gt;

    Hello www.google.com World http://yahoo.com

I am not looking for specific URLs in the string. I am looking for ALL of the URLs in the string which is why I need a regular expression.

Regular expression to find URLs within a string

I am reading Accelerated C++ by Koenig. He writes that &quot;the new idea is that we can use + to concatenate a string and a string literal - or, for that matter, two strings (but not two string literals).

Fine, this makes sense I suppose. Now onto two separate exercises meant to illuminate this . 

Are the following definitions valid?

    const string hello = &quot;Hello&quot;;
    
    const string message = hello + &quot;,world&quot; + &quot;!&quot;;

Now, I tried to execute the above and it worked! So I was happy.

Then I tried to do the next exercise; 

    const string exclam = &quot;!&quot;;
    
    const string message = &quot;Hello&quot; + &quot;,world&quot; + exclam;

This did not work. Now I understand it has something to do with the fact that you cannot concatenate two string literals, but I don&#39;t understand the semantic difference between why I managed to get the first example to work (isn&#39;t &quot;,world&quot; and &quot;!&quot; two string literals? Shouldn&#39;t this not have worked?) but not the second.


Concatenate two string literals

I would like to use the .replace function to replace multiple strings.

I currently have  

    string.replace(&quot;condition1&quot;, &quot;&quot;)

but would like to have something like

    string.replace(&quot;condition1&quot;, &quot;&quot;).replace(&quot;condition2&quot;, &quot;text&quot;)

although that does not feel like good syntax

what is the proper way to do this? kind of like how in grep/regex you can do `\1` and `\2` to replace fields to certain search strings

How to replace multiple substrings of a string?

I&#39;d like to know how to replace a capture group with its uppercase in JavaScript. Here&#39;s a simplified version of what I&#39;ve tried so far that&#39;s not working:

    &gt; a=&quot;foobar&quot;
    &#39;foobar&#39;
    &gt; a.replace( /(f)/, &quot;$1&quot;.toUpperCase() )
    &#39;foobar&#39;
    &gt; a.replace( /(f)/, String.prototype.toUpperCase.apply(&quot;$1&quot;) )
    &#39;foobar&#39;

Would you explain what&#39;s wrong with this code?

Replace a Regex capture group with uppercase in Javascript

When doing search/replace in vim, I almost never need to use regex, so it&#39;s a pain to constantly be escaping everything, Is there a way to make it default to not using regex or is there an alternative command to accomplish this?

As an example, if I want to replace `&lt;` with `&amp;lt;`, I&#39;d like to just be able to type `s/&lt;/&amp;lt;/g` instead of `s/\&lt;/\&amp;lt\;/g`

Perform a non-regex search/replace in vim

What is the fastest way to replace extra white spaces to one white space?  
e.g.

*from* 

    foo      bar 
*to*

    foo bar



c# Fastest way to remove extra white spaces

I have a string in which I need to replace markers with values from a dictionary. It has to be as efficient as possible. Doing a loop with a string.replace is just going to consume memory (strings are immutable, remember). Would StringBuilder.Replace() be any better since this is was designed to  work with string manipulations?

I was hoping to avoid the expense of RegEx, but if that is going to be a more efficient then so be it. 

Note: I don&#39;t care about code complexity, only how fast it runs and the memory it consumes. 

Average stats: 255-1024 characters in length, 15-30 keys in the dictionary.

Content Type	Original Author	Original Content on Stackoverflow
Question	jblu09	View Question on Stackoverflow
Solution 1 - Python	Fred Nurk	View Answer on Stackoverflow
Solution 2 - Python	Hassan Raza	View Answer on Stackoverflow
Solution 3 - Python	sergiol	View Answer on Stackoverflow

Replace first occurrence only of a string?

Python Problem Overview

Python Solutions

Solution 1 - Python

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How to force a list to a fixed size?

How to sort the files according to the time stamp in unix?

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