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Convert a list of data frames into one data frame
I have code that at one place ends up with a list of data frames which I really want to convert to a single big data frame.
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Declaring variables inside or outside of a loop
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The scope of local variables should always be the smallest possible.
In your example I presume str is not used outside of the while loop, otherwise you would not be asking the question, because declaring it inside the while loop would not be an option, since it would not comp...
Is there any way to put malicious code into a regular expression?
...o solve. These may only show up on particular input data, but one can generally create one wherein this doesn’t matter.
Which ones these are will depend somewhat on how smart the regex compiler you’re using happens to be, because some of these can be detected during compilation time. Regex com...
JavaScript seconds to time string with format hh:mm:ss
... Thanks for the prototype idea, I like how it is easier to call it. I prototyped the Number so I can call it on them too. I also found this answer that would remove the hours and minutes if they were not needed.
– alunsford3
May 25 '12 at 5:44
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Deep null checking, is there a better way?
...'d say
cake?.frosting?.berries?.loader
and the compiler would generate all the short-circuiting checks for you.
It didn't make the bar for C# 4. Perhaps for a hypothetical future version of the language.
Update (2014):
The ?. operator is now planned for the next Roslyn compiler release. Note ...
Crontab Day of the Week syntax
...day
5 - Fri Friday
6 - Sat Saturday
7 - Sun Sunday
Graphically:
┌────────── minute (0 - 59)
│ ┌──────── hour (0 - 23)
│ │ ┌────── day of month (1 - 31)
│ │ │ ┌──── month (1 - 12)
│ │ │ │ ┌─...
Where can I find the Java SDK in Linux after installing it?
I installed JDK using apt-get install but I don't know where my jdk folder is. I need to set the path for that. Does any one have a clue on the location?
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How do you run a Python script as a service in Windows?
...braries that come included with ActivePython or can be installed with pywin32 (Python for Windows extensions).
This is a basic skeleton for a simple service:
import win32serviceutil
import win32service
import win32event
import servicemanager
import socket
class AppServerSvc (win32serviceutil.Ser...
stopPropagation vs. stopImmediatePropagation
...“parent”, but in reality both also stops entering children as well if called in the capture phase! See my answer for details.
– Robert Siemer
Mar 26 at 7:07
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Simple way to find if two different lists contain exactly the same elements?
...he specified object is
also a list, both lists have the same
size, and all corresponding pairs of
elements in the two lists are equal.
(Two elements e1 and e2 are equal if
(e1==null ? e2==null :
e1.equals(e2)).) In other words, two
lists are defined to be equal if they
contain the sa...