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How can I remove a flag in C?
...ation of the flag you want to unset. A Bitwise NOT inverts every bit (i.e. 0 => 1, 1 => 0).
flags = flags & ~MASK; or flags &= ~MASK;.
Long Answer
ENABLE_WALK = 0 // 00000000
ENABLE_RUN = 1 // 00000001
ENABLE_SHOOT = 2 // 00000010
ENABLE_SHOOTRUN = 3 // 00000011
value ...
Resizing an image in an HTML5 canvas
...lement them yourself then! Oh come on, we're entering the new age of Web 3.0, HTML5 compliant browsers, super optimized JIT javascript compilers, multi-core(†) machines, with tons of memory, what are you afraid of? Hey, there's the word java in javascript, so that should guarantee the performance,...
How should I validate an e-mail address?
...am", as will org.apache.commons.validator.routines.EmailValidator)
(?:[a-z0-9!#$%&'*+/=?^_`{|}~-]+(?:\.[a-z0-9!#$%&'*+/=?^_`{|}~-]+)*|"(?:[\x01-\x08\x0b\x0c\x0e-\x1f\x21\x23-\x5b\x5d-\x7f]|\\[\x01-\x09\x0b\x0c\x0e-\x7f])*")@(?:(?:[a-z0-9](?:[a-z0-9-]*[a-z0-9])?\.)+[a-z0-9](?:[a-z0-9-]*[a-z0...
Why is a round-trip conversion via a string not safe for a double?
...mber->precision = precision;
if (((FPDOUBLE*)&value)->exp == 0x7FF) {
number->scale = (((FPDOUBLE*)&value)->mantLo || ((FPDOUBLE*)&value)->mantHi) ? SCALE_NAN: SCALE_INF;
number->sign = ((FPDOUBLE*)&value)->sign;
number->digits[0] =...
0.1 float is greater than 0.1 double. I expected it to be false [duplicate]
...loat. float has 24 binary bits of precision, and double has 53. In binary, 0.1 is:
0.1₁₀ = 0.0001100110011001100110011001100110011001100110011…₂
^ ^ ^ ^
1 10 20 24
So if we round up at the 24th digit, we'll get
0.1₁₀ ~ 0.00011...
What to do about Eclipse's “No repository found containing: …” error messages?
...
450
Quick answer
Go to Help → Install new software → Here uncheck “Contact all update sites d...
SVG get text element width
...|
edited Jan 21 '13 at 18:04
RobM
7,08722 gold badges3838 silver badges3636 bronze badges
answered Oct 2...
Why does GCC generate 15-20% faster code if I optimize for size instead of speed?
I first noticed in 2009 that GCC (at least on my projects and on my machines) have the tendency to generate noticeably faster code if I optimize for size ( -Os ) instead of speed ( -O2 or -O3 ), and I have been wondering ever since why.
...
Regex group capture in R with multiple capture-groups
...roup in the match (and one for the whole match):
> s = c("(sometext :: 0.1231313213)", "(moretext :: 0.111222)")
> str_match(s, "\\((.*?) :: (0\\.[0-9]+)\\)")
[,1] [,2] [,3]
[1,] "(sometext :: 0.1231313213)" "sometext" "0.1231313213"
[2,] "(moretex...
How to find the installed pandas version
...ersion__:
In [76]: import pandas as pd
In [77]: pd.__version__
Out[77]: '0.12.0-933-g281dc4e'
Pandas also provides a utility function, pd.show_versions(), which reports the version of its dependencies as well:
In [53]: pd.show_versions(as_json=False)
INSTALLED VERSIONS
------------------
commi...