By using `&#39;&#39;.join`

    list1 = [&#39;1&#39;, &#39;2&#39;, &#39;3&#39;]
    str1 = &#39;&#39;.join(list1)

Or if the list is of integers, convert the elements before joining them.

    list1 = [1, 2, 3]
    str1 = &#39;&#39;.join(str(e) for e in list1)


    &gt;&gt;&gt; L = [1,2,3]       
    &gt;&gt;&gt; &quot; &quot;.join(str(x) for x in L)
    &#39;1 2 3&#39;

    L = [&#39;L&#39;,&#39;O&#39;,&#39;L&#39;]
    makeitastring = &#39;&#39;.join(map(str, L))

What is the best way to randomize the order of a generic list in C#? I&#39;ve got a finite set of 75 numbers in a list I would like to assign a random order to, in order to draw them for a lottery type application.

Randomize a List&lt;T&gt;

Is it possible to use `ls` in Unix to list the total size of a sub-directory and all its contents as opposed to the usual `4K` that (I assume) is just the directory file itself?

    total 12K
    drwxrwxr-x  6 *** *** 4.0K 2009-06-19 10:10 branches
    drwxrwxr-x 13 *** *** 4.0K 2009-06-19 10:52 tags
    drwxrwxr-x 16 *** *** 4.0K 2009-06-19 10:02 trunk

After scouring the man pages I&#39;m coming up empty.


Using ls to list directories and their total sizes

How can I convert a list to a string using Python?

How to convert list to string

<p>How can I convert a list to a string using Python?</p>


In my code I ask the user for a date in the format `dd/mm/yyyy`.

    currentdate = raw_input(&quot;Please enter todays date in the format dd/mm/yyyy: &quot;)
    day,month,year = currentdate.split(&#39;/&#39;)
    today = datetime.date(int(year),int(month),int(day))
   
This returns the error

 &gt; TypeError: descriptor &#39;date&#39; requires a &#39;datetime.datetime&#39; object but received a &#39;int&#39; 

if I remove the `int()` then I end up with the same error only it says it received a `&#39;str&#39;`

What am I doing wrong?

Troubleshooting &quot;descriptor &#39;date&#39; requires a &#39;datetime.datetime&#39; object but received a &#39;int&#39;&quot;

i have a little problem with my script, where i need to convert ip in form &#39;xxx.xxx.xxx.xxx&#39; to integer representation and go back from this form.

    def iptoint(ip):
    	return int(socket.inet_aton(ip).encode(&#39;hex&#39;),16)
	
    def inttoip(ip):
    	return socket.inet_ntoa(hex(ip)[2:].decode(&#39;hex&#39;))
    
    
    In [65]: inttoip(iptoint(&#39;192.168.1.1&#39;))
    Out[65]: &#39;192.168.1.1&#39;
    
    In [66]: inttoip(iptoint(&#39;4.1.75.131&#39;))
    ---------------------------------------------------------------------------
    error                                     Traceback (most recent call last)
    
    /home/thc/&lt;ipython console&gt; in &lt;module&gt;()
    
    /home/thc/&lt;ipython console&gt; in inttoip(ip)
    
    error: packed IP wrong length for inet_ntoa`

Anybody knows how to fix that?

Conversion from IP string to integer, and backward in Python

How do you calculate program run time in python?

I&#39;m trying to create a file that is only user-readable and -writable (`0600`).

Is the only way to do so by using `os.open()` as follows? 

    import os
    fd = os.open(&#39;/path/to/file&#39;, os.O_WRONLY, 0o600)
    myFileObject = os.fdopen(fd)
    myFileObject.write(...)
    myFileObject.close()

Ideally, I&#39;d like to be able to use the `with` keyword so I can close the object automatically. Is there a better way to do what I&#39;m doing above? 

Write file with specific permissions in Python

I am trying to understand, what is monkey patching or a monkey patch? 

Is that something like methods/operators overloading or delegating? 

Does it have anything common with these things?

What is monkey patching?

I have found very similar posts, but I can&#39;t quite get my regular expression right here.

I am trying to write a regular expression which returns a string which is between two other strings. For example: I want to get the string which resides between the strings &quot;cow&quot; and &quot;milk&quot;.

&gt; My cow always gives milk

would return

&gt; &quot;always gives&quot;

Here is the expression I have pieced together so far:

    (?=cow).*(?=milk)

However, this returns the string &quot;cow always gives&quot;.




Regular expression to get a string between two strings in Javascript

I need some help on declaring a regex. My inputs are like the following:

```none
this is a paragraph with&lt;[1&gt; in between&lt;/[1&gt; and then there are cases ... where the&lt;[99&gt; number ranges from 1-100&lt;/[99&gt;. 
and there are many other lines in the txt files
with&lt;[3&gt; such tags &lt;/[3&gt;
```

The required output is:

```none
this is a paragraph with in between and then there are cases ... where the number ranges from 1-100. 
and there are many other lines in the txt files
with such tags
```

I&#39;ve tried this:

    #!/usr/bin/python
    import os, sys, re, glob
    for infile in glob.glob(os.path.join(os.getcwd(), &#39;*.txt&#39;)):
    	for line in reader: 
    		line2 = line.replace(&#39;&lt;[1&gt; &#39;, &#39;&#39;)
    		line = line2.replace(&#39;&lt;/[1&gt; &#39;, &#39;&#39;)
    		line2 = line.replace(&#39;&lt;[1&gt;&#39;, &#39;&#39;)
    		line = line2.replace(&#39;&lt;/[1&gt;&#39;, &#39;&#39;)
    		
    		print line

I&#39;ve also tried this (but it seems like I&#39;m using the wrong regex syntax):

    		line2 = line.replace(&#39;&lt;[*&gt; &#39;, &#39;&#39;)
    		line = line2.replace(&#39;&lt;/[*&gt; &#39;, &#39;&#39;)
    		line2 = line.replace(&#39;&lt;[*&gt;&#39;, &#39;&#39;)
    		line = line2.replace(&#39;&lt;/[*&gt;&#39;, &#39;&#39;)

I dont want to hard-code the `replace` from 1 to 99.

How to input a regex in string.replace?

PHP - Is there a quick, on-the-fly method to test for a single character string, then prepend a leading zero?

Example:

    $year = 11;
    $month = 4;
    
    $stamp = $year.add_single_zero_if_needed($month);  // Imaginary function
    
    echo $stamp; // 1104

PHP prepend leading zero before single digit number, on-the-fly

I have the following in my application controller:

    def is_number?(object)
      true if Float(object) rescue false
    end

and the following condition in my controller:

    if mystring.is_number?
    
    end

The condition is throwing an `undefined method` error. I&#39;m guessing I&#39;ve defined `is_number` in the wrong place...?

Test if string is a number in Ruby on Rails

I want to fill out a string with spaces. I know that the following works for zero&#39;s:

    &gt;&gt;&gt; print  &quot;&#39;%06d&#39;&quot;%4
    &#39;000004&#39;

But what should I do when I want this?:

    &#39;hi    &#39;

of course I can measure string length and do `str+&quot; &quot;*leftover`, but I&#39;d like the shortest way.

How can I fill out a Python string with spaces?

I have a List, which may contain elements that will compare as equal. I would like a similar List, but with one element removed. So from (A, B, C, B, D) I would like to be able to &quot;remove&quot; just one B to get e.g. (A, C, B, D). The order of the elements in the result does not matter.

I have working code, written in a Lisp-inspired way in Scala. Is there a more idiomatic way
to do this?

The context is a card game where two decks of standard cards are in play, so there may
be duplicate cards but still played one at a time.

    def removeOne(c: Card, left: List[Card], right: List[Card]): List[Card] = {
      if (Nil == right) {
        return left
      }
      if (c == right.head) {
        return left ::: right.tail
      }
      return removeOne(c, right.head :: left, right.tail)
    }
  
    def removeCard(c: Card, cards: List[Card]): List[Card] = {
      return removeOne(c, Nil, cards)
    }


What is an idiomatic Scala way to &quot;remove&quot; one element from an immutable List?

For example, I have two lists  

     A           = [6, 7, 8, 9, 10, 11, 12]
    subset_of_A  = [6, 9, 12]; # the subset of A
    
    
    the result should be [7, 8, 10, 11]; the remaining elements 

Is there a built-in function in python to do this?

array filter in python?

Please consider the following code:

    i = [1, 2, 3, 5, 8, 13]
    j = []
    k = 0
    
    for l in i:
        j[k] = l
        k += 1
    
    print j

The output (Python 2.6.6 on Win 7 32-bit) is:

    &gt; Traceback (most recent call last): 
    &gt;     j[k] = l IndexError: list assignment index out of range

I guess it&#39;s something simple I don&#39;t understand. Can someone clear it up?

Why does this iterative list-growing code give IndexError: list assignment index out of range?

The following code (run in android) always gives me a ClassCastException in the 3rd line:

    final String[] v1 = i18nCategory.translation.get(id);
    final ArrayList&lt;String&gt; v2 = new ArrayList&lt;String&gt;(Arrays.asList(v1));
    String[] v3 = (String[])v2.toArray();

It happens also when v2 is Object[0] and also when there are Strings in it.
Any Idea why?

java: (String[])List.toArray() gives ClassCastException

Let&#39;s say I have a list like this:

    mylist = [[&quot;A&quot;,0], [&quot;B&quot;,1], [&quot;C&quot;,0], [&quot;D&quot;,2], [&quot;E&quot;,2]]

How can I most elegantly group this to get this list output in Python:

    [[&quot;A&quot;, &quot;C&quot;], [&quot;B&quot;], [&quot;D&quot;, &quot;E&quot;]]

So the values are grouped by the secound value but the order is preserved...


Content Type	Original Author	Original Content on Stackoverflow
Question	Nm3	View Question on Stackoverflow
Solution 1 - Python	Senthil Kumaran	View Answer on Stackoverflow
Solution 2 - Python	Andrey Sboev	View Answer on Stackoverflow
Solution 3 - Python	Nathan	View Answer on Stackoverflow

How to convert list to string

Python Problem Overview

Python Solutions

Solution 1 - Python

Solution 2 - Python

Solution 3 - Python

Using ls to list directories and their total sizes

Randomize a List<T>

Attributions