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C/C++ check if one bit is set in, i.e. int variable
Is there such a way to check if bit 3 in temp is 1 or 0 without bit shifting and masking.
21 Answers
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Java regex capturing groups indexes
... e.g. (\.\w+)+, or to specify where alternation should take effect, e.g. ^(0*1|1*0)$ (^, then 0*1 or 1*0, then $) versus ^0*1|1*0$ (^0*1 or 1*0$).
A capturing group, apart from grouping, will also record the text matched by the pattern inside the capturing group (pattern). Using your example, (.*):...
Bootstrap carousel multiple frames at once
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20
Can this be done with bootstrap 3's carousel? I'm hoping I won't have
to go hunting for yet...
How to remove leading zeros from alphanumeric text?
...s leading zeroes, but leaves one if necessary (i.e. it wouldn't just turn "0" to a blank string).
s.replaceFirst("^0+(?!$)", "")
The ^ anchor will make sure that the 0+ being matched is at the beginning of the input. The (?!$) negative lookahead ensures that not the entire string will be matched....
Selecting data frame rows based on partial string match in a column
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150
I notice that you mention a function %like% in your current approach. I don't know if that's a r...
How to create a video from images with FFmpeg?
...video filter instead of -r for the output framerate
ffmpeg -r 1/5 -i img%03d.png -c:v libx264 -vf fps=25 -pix_fmt yuv420p out.mp4
Alternatively the format video filter can be added to the filter chain to replace -pix_fmt yuv420p like "fps=25,format=yuv420p". The advantage of this method is th...
What is the easiest way to push an element to the beginning of the array?
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390
What about using the unshift method?
ary.unshift(obj, ...) → ary
Prepends objects to the...
Javascript seconds to minutes and seconds
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To get the number of full minutes, divide the number of total seconds by 60 (60 seconds/minute):
var minutes = Math.floor(time / 60);
And to get the remaining seconds, multiply the full minutes with 60 and subtract from the total seconds:
var seconds = time - minutes * 60;
Now if you also wan...
How to fix the uninitialized constant Rake::DSL problem on Heroku?
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205
Put this in your Rakefile above require 'rake':
require 'rake/dsl_definition'
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What is “entropy and information gain”?
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1051
I assume entropy was mentioned in the context of building decision trees.
To illustrate, imag...