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Unicode equivalents for \w and \b in Java regular expressions?
...s Regex Unicode Problems
The problem with Java regexes is that the Perl 1.0 charclass escapes — meaning \w, \b, \s, \d and their complements — are not in Java extended to work with Unicode. Alone amongst these, \b enjoys certain extended semantics, but these map neither to \w, nor to Unicode i...
How to check if a value exists in a dictionary (python)
...rative timing:
>>> T(lambda : 'one' in d.itervalues()).repeat()
[0.28107285499572754, 0.29107213020324707, 0.27941107749938965]
>>> T(lambda : 'one' in d.values()).repeat()
[0.38303399085998535, 0.37257885932922363, 0.37096405029296875]
>>> T(lambda : 'one' in d.viewvalue...
Remove rows with all or some NAs (missing values) in data.frame
...
1080
Also check complete.cases :
> final[complete.cases(final), ]
gene hsap mmul m...
Python division
I was trying to normalize a set of numbers from -100 to 0 to a range of 10-100 and was having problems only to notice that even with no variables at all, this does not evaluate the way I would expect it to:
...
How to get first character of string?
...
1080
What you want is charAt.
var x = 'some string';
alert(x.charAt(0)); // alerts 's'
...
Suppress Scientific Notation in Numpy When Creating Array From Nested List
...ons(suppress=True), for details see here:
http://pythonquirks.blogspot.fr/2009/10/controlling-printing-in-numpy.html
For SciPy.org numpy documentation, which includes all function parameters (suppress isn't detailed in the above link), see here: https://docs.scipy.org/doc/numpy/reference/generated/...
Is it worth using Python's re.compile?
...
I've had a lot of experience running a compiled regex 1000s of times versus compiling on-the-fly, and have not noticed any perceivable difference. Obviously, this is anecdotal, and certainly not a great argument against compiling, but I've found the difference to be negligible.
...
Which is faster: while(1) or while(2)?
...arying levels of optimization:
int main(void) {
while(1) {}
return 0;
}
int main(void) {
while(2) {}
return 0;
}
Even with no optimizations (-O0), the generated assembly was identical for both programs. Therefore, there is no speed difference between the two loops.
For reference, ...
Is there a difference between YES/NO,TRUE/FALSE and true/false in objective-c?
.../TRUE/true were all defined as 1 and NO/FALSE/false were all defined as 0 . Is there really any difference?
9 Answers
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Filter rows which contain a certain string
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mpg cyl disp hp drat wt qsec vs am gear carb type
1 21.0 6 160.0 110 3.90 2.620 16.46 0 1 4 4 Mazda RX4
2 21.0 6 160.0 110 3.90 2.875 17.02 0 1 4 4 Mazda RX4 Wag
3 33.9 4 71.1 65 4.22 1.835 19.90 1 1 4 1 Toyota Corolla
4 21.5 4 120.1 97 3....