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List distinct values in a vector in R
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answered Oct 13 '11 at 14:08
csgillespiecsgillespie
52.3k1313 gold badges127127 silver badges169169 bronze badges
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What is “lifting” in Scala?
...ion.
scala> val pf: PartialFunction[Int, Boolean] = { case i if i > 0 => i % 2 == 0}
pf: PartialFunction[Int,Boolean] = <function1>
scala> pf.lift
res1: Int => Option[Boolean] = <function1>
scala> res1(-1)
res2: Option[Boolean] = None
scala> res1(1)
res3: Option[...
How to concatenate twice with the C preprocessor and expand a macro as in “arg ## _ ## MACRO”?
...u need the equivalent trick with the stringizing operator too.
Section 6.10.3 of the C99 standard covers 'macro replacement', and 6.10.3.1 covers 'argument substitution'.
After the arguments for the invocation of a function-like macro have been identified,
argument substitution takes place. A...
How do I force detach Screen from another SSH session?
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answered May 2 '14 at 21:10
Matt S.Matt S.
2,70611 gold badge1010 silver badges44 bronze badges
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Why do I get TypeError: can't multiply sequence by non-int of type 'float'?
...g to get a sale amount (by input) to be multiplied by a defined sales tax (0.08) and then have it print the total amount (sales tax times sale amount).
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MySQL 'create schema' and 'create database' - Is there any difference
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140
The documentation of MySQL says :
CREATE DATABASE creates a database
with the given name....
Argparse optional positional arguments?
...tion='store_true')
_StoreTrueAction(option_strings=['-v'], dest='v', nargs=0, const=True, default=False, type=None, choices=None, help=None, metavar=None)
>>> parser.add_argument('dir', nargs='?', default=os.getcwd())
_StoreAction(option_strings=[], dest='dir', nargs='?', const=None, defaul...
How to open a file using the open with statement
...n infile:
if line.startswith(txt):
line = line[0:len(txt)] + ' - Truly a great person!\n'
outfile.write(line)
# input the name you want to check against
text = input('Please enter the name of a great person: ')
letsgo = filter(text,'Spanish', 'Spanish2')
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How to set custom location for local installation of npm package?
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180
TL;DR
You can do this by using the --prefix flag and the --global* flag.
pje@friendbear:~/foo $ ...
How to track child process using strace?
I used strace to attach to a process briefly. The process created 90 threads. When I found the offending thread, I had to tediously search for the parent thread, then the grandparent thread, and so on all the way to the root process.
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