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Split Java String by New Line
...rea using a regex to split the String by \n However, this does not work and I also tried by \r\n|\r|n and many other combination of regexes.
Code:
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pandas: multiple conditions while indexing data frame - unexpected behavior
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As you can see, the AND operator drops every row in which at least one
value equals -1. On the other hand, the OR operator requires both
values to be equal to -1 to drop them.
That's right. Remember that you're writing the condition in te...
Android. Fragment getActivity() sometimes returns null
...ole error reports sometimes I see reports with NPE issue. I do not understand what is wrong with my code. On emulator and my device application works good without forcecloses, however some users get NullPointerException in fragment class when the getActivity() method is called.
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What is your single most favorite command-line trick using Bash? [closed]
...es with suffixes quickly:
cp /home/foo/realllylongname.cpp{,-old}
This expands to:
cp /home/foo/realllylongname.cpp /home/foo/realllylongname.cpp-old
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answered Sep 16 '0...
Entity Framework Provider type could not be loaded?
...ed this too. If you create a library that uses EF, VS will put the EF.dll and the EF.SqlServer.dll into that build folder. But if you now have another program make use of your library, only the EF.dll will be put into this build folder. The EF.SqlServer.dll is missing. If you add it manually to ...
Is there any reason to use a synchronous XMLHttpRequest?
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I think they might become more popular as HTML 5 standards progress. If a web application is given access to web workers, I could foresee developers using a dedicated web worker to make synchronous requests for, as Jonathan said, to ensure one request happens before another....
Export and Import all MySQL databases at one time
...re than 100 MySQL databases. I want to export all of them at the same time and again import all of them into my MySQL server at one time. How can I do that?
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When to use virtual destructors?
I have a solid understanding of most OOP theory but the one thing that confuses me a lot is virtual destructors.
17 Answe...
How do I find the time difference between two datetime objects in python?
...nly holds the difference.
In the example above it is 0 minutes, 8 seconds and 562000 microseconds.
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What's better at freeing memory with PHP: unset() or $var = null
...is garbage-collected.) (bug 33595)
The question "difference between unset and = null" details some differences:
unset($a) also removes $a from the symbol table; for example:
$a = str_repeat('hello world ', 100);
unset($a);
var_dump($a);
Outputs:
Notice: Undefined variable: a in xxx
NULL
But ...