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How to concatenate two strings to build a complete path
... a directory. Then I want to append some strings at the end of this string and build a path to some subdirectories.
For example assume user enters an string like this:
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Why should I declare a virtual destructor for an abstract class in C++?
... abstract classes that function as interfaces? Please provide some reasons and examples why.
7 Answers
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Round to at most 2 decimal places (only if necessary)
... @James Wow that's really weird- I'm working in the Chrome dev console and I'm noticing that 1.005 * 100 = 100.49999999999999. Math.round(100.49999999999999) evaluates to 100, whereas Math.round(100.5) evaluates to 101. IE9 does the same thing. This is due to floating point weirdness in javascri...
Convert datetime object to a String of date only in Python
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date and datetime objects (and time as well) support a mini-language to specify output, and there are two ways to access it:
direct method call: dt.strftime('format here'); and
new format method: '{:format here}'.format(dt)
So...
What is in your Mathematica tool bag? [closed]
...ned this before, but the tool I find most useful is an application of Reap and Sow which mimics/extends the behavior of GatherBy:
SelectEquivalents[x_List,f_:Identity, g_:Identity, h_:(#2&)]:=
Reap[Sow[g[#],{f[#]}]&/@x, _, h][[2]];
This allows me to group lists by any criteria and tran...
How to obtain the number of CPUs/cores in Linux from the command line?
... awk '{print $4}'
which should return (for example) 8 (whereas the command above would return 16)
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How to perform runtime type checking in Dart?
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is and is! can be found in the Operators section of the Dart language tour.
– Curly
Jun 25 '19 at 16:02
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Remote connect to clearDB heroku database
...eroku using for example MySQL Query Browser. Where to get url, port, login and password?
12 Answers
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Docker: adding a file from a parent directory
...way to do the same trick in Docker Hub?
– Marcel Hernandez
Mar 25 '16 at 20:31
Not that I know of. You could push the ...
What is the “N+1 selects problem” in ORM (Object-Relational Mapping)?
...erally stated as a problem in Object-Relational mapping (ORM) discussions, and I understand that it has something to do with having to make a lot of database queries for something that seems simple in the object world.
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