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Updating packages in Emacs
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In order to automatically update the list of packages, only if there is no package list already, use the following:
(when (not package-archive-contents)
(package-refresh-contents))
In order to update all installed packages, type package-li...
Extract a regular expression match
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Use the new stringr package which wraps all the existing regular expression operates in a consistent syntax and adds a few that are missing:
library(stringr)
str_locate("aaa12xxx", "[0-9]+")
# start end
# [1,] 4 5
str_extract("aaa12xxx", "[0-9]+")
# [1]...
How much is the overhead of smart pointers compared to normal pointers in C++?
..._ptr always has memory overhead for reference counter, though it is very small.
std::unique_ptr has time overhead only during constructor (if it has to copy the provided deleter and/or null-initialize the pointer) and during destructor (to destroy the owned object).
std::shared_ptr has time overhe...
Convert System.Drawing.Color to RGB and Hex Value
...t be null and c.R.ToString(), c.G.ToString(), and c.B.ToString() can't actually fail (the only way I can see them failing is with a NullReferenceException, and none of them can actually be null).
You could clean the whole thing up using the following:
private static String HexConverter(System.Draw...
Does SQLAlchemy have an equivalent of Django's get_or_create?
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That's basically the way to do it, there is no shortcut readily available AFAIK.
You could generalize it ofcourse:
def get_or_create(session, model, defaults=None, **kwargs):
instance = session.query(model).filter_by(**kwargs).firs...
Print all day-dates between two dates [duplicate]
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Hello all, i tried it but It prints only the last day, i need full list day dates_list = [] result = d1 + td(days=i) dates_list.append(result) print(result) It prints only the last day, how to solve this?
– Dr...
The $.param( ) inverse function in JavaScript / jQuery
...ht with accepted answer "this won't work with arrays". Your solution works all right.
– Robert Koritnik
Sep 16 '09 at 12:44
add a comment
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Bash function to find newest file matching pattern
... Your one liner is giving me right answer, but the "right" way is actually giving me the oldest file. Any idea why?
– NewNameStat
Apr 4 '19 at 21:59
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python pandas remove duplicate columns
...he given example, the returned value would be [False,False,True].
Pandas allows one to index using boolean values whereby it selects only the True values. Since we want to keep the unduplicated columns, we need the above boolean array to be flipped (ie [True, True, False] = ~[False,False,True])
F...
How to reference generic classes and methods in xml documentation
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Thanks for that answer! It's actually missing from MSDN's page on <see>: msdn.microsoft.com/en-us/library/acd0tfbe.aspx
– joce
Apr 16 '11 at 20:56
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