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Unique combination of all elements from two (or more) vectors
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this maybe what you are after
> expand.grid(a,b)
Var1 Var2
1 ABC 2012-05-01
2 DEF 2012-05-01
3 GHI 2012-05-01
4 ABC 2012-05-02
5 DEF 2012-05-02
6 GHI 2012-05-02
7 ABC 2012-05-03
8 DEF 2012-05-03
9 GHI 2012-05-03
10 ABC 2012-05-04
11...
Joda-Time: what's the difference between Period, Interval and Duration?
... are defined e.g. this might be the interval between 20:00:00GMT yesterday and 09:00:00GMT this morning.
A duration in Joda-Time represents a duration of time measured in milliseconds. The duration is often obtained from an interval. i.e. we can subtract start from end of an interval to derive a du...
Why are we not to throw these exceptions?
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Exception is the base type for all exceptions, and as such terribly unspecific. You shouldn’t ever throw this exception because it simply does not contain any useful information. Calling code catching for exceptions couldn’t disambiguate the intentionally thrown excep...
Grepping a huge file (80GB) any way to speed it up?
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Here are a few options:
1) Prefix your grep command with LC_ALL=C to use the C locale instead of UTF-8.
2) Use fgrep because you're searching for a fixed string, not a regular expression.
3) Remove the -i option, if you don't need it.
So your command becomes:
LC_ALL=C ...
Default initialization of std::array?
...zed (C++11 §8.5/11). That includes objects of type std::array<T, N> and T[N].
Be aware that there are types for which default initialization has no effect and leaves the object's value indeterminate: any non-class, non-array type (§8.5/6). Consequently, a default-initialized array of object...
Wait for a void async method
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Best practice is to mark function async void only if it is fire and forget method, if you want to await on, you should mark it as async Task.
In case if you still want to await, then wrap it like so await Task.Run(() => blah())
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Multiple commands in gdb separated by some sort of delimiter ';'?
I am trying to execute two commands at once in gdb:
6 Answers
6
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How to add to an existing hash in Ruby
...ash in Ruby, I'm in the process of working through Apress' Beginning Ruby and have just finished the hashes chapter.
7 Ans...
Do regular expressions from the re module support word boundaries (\b)?
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ahh after yours and Bolo's suggestion, it was because I wasn't using a raw string. Thanks!
– D.C.
Oct 22 '10 at 8:46
9
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How do I break out of a loop in Perl?
... edited Jan 5 '18 at 17:41
Alexander Roskamp
2766 bronze badges
answered Nov 19 '08 at 20:23
Zain RizviZain R...