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Split comma-separated strings in a column into separate rows
...me number of strings. i.e. data.table(id= "X21", a = "chr1;chr1;chr1", b="123;133;134",c="234;254;268") becoming data.table(id = c("X21","X21",X21"), a=c("chr1","chr1","chr1"), b=c("123","133","134"), c=c("234","254","268")) ?
– Reilstein
Jan 19 '19 at 1:39
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Output to the same line overwriting previous output?
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Here's code for Python 3.x:
print(os.path.getsize(file_name)/1024+'KB / '+size+' KB downloaded!', end='\r')
The end= keyword is what does the work here -- by default, print() ends in a newline (\n) character, but this can be replaced with a different string...
Python argparse mutual exclusive group
... answered Dec 28 '14 at 10:38
Oz123Oz123
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Static method behavior in multi-threaded environment in java
...d try and explain at a slightly more simple level for anybody who comes across this and is newish to Java. Here goes..
Memory in java is split up into two kinds - the heap and the stacks. The heap is where all the objects live and the stacks are where the threads do their work. Each thread has its ...
Best way to represent a fraction in Java?
...on("Unknown format '" + s + "'");
}
// this translates 23.123e5 to 25,123 / 1000 * 10^5 = 2,512,300 / 1 (GCD)
String whole = m.group(1);
String decimal = m.group(2);
String exponent = m.group(3);
String n = whole;
// 23.123 => 23123
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What is the difference between a thread and a fiber?
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In the most simple terms, threads are generally considered to be preemptive (although this may not always be true, depending on the operating system) while fibers are considered to be light-weight, cooperative threads. Both are separ...
How to insert a newline in front of a pattern?
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This works in bash and zsh, tested on Linux and OS X:
sed 's/regexp/\'$'\n/g'
In general, for $ followed by a string literal in single quotes bash performs C-style backslash substitution, e.g. $'\t' is translated to a literal tab. Plus, sed wants your newline literal to...
What is the meaning and difference between subject, user and principal?
...clarify "User - subset of principal"? If John is the subject and "account #123" is his principal, the user is who? Are there two John's? Since Genus > Species > Individual is increasingly specific, John (user) should be more specific than John (subject). Or am I missing something?
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What are file descriptors, explained in simple terms?
...formation about that opened file. So if there are 100 files opened in your OS then there will be 100 entries in OS (somewhere in kernel). These entries are represented by integers like (...100, 101, 102....). This entry number is the file descriptor.
So it is just an integer number that uniquely rep...
How does Apple find dates, times and addresses in emails?
In the iOS email client, when an email contains a date, time or location, the text becomes a hyperlink and it is possible to create an appointment or look at a map simply by tapping the link. It not only works for emails in English, but in other languages also. I love this feature and would like to ...