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Positive Number to Negative Number in JavaScript?
...the ~ bitwise operator.
For example, if you have a = 1000 and you need to convert it to a negative, you could do the following:
a = ~a + 1;
Which would result in a being -1000.
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Why do C and C++ compilers allow array lengths in function signatures when they're never enforced?
...actually ignored.
The decision to allow this syntax was made in the 1970s and has caused much confusion ever since...
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Append values to a set in Python
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The way I like to do this is to convert both the original set and the values I'd like to add into lists, add them, and then convert them back into a set, like this:
setMenu = {"Eggs", "Bacon"}
print(setMenu)
> {'Bacon', 'Eggs'}
setMenu = set(list(setMen...
Declaring variables inside loops, good practice or bad practice?
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The compiler knows that the variable scope is limited to inside the loop, and therefore will issue a proper error message if the variable is by mistake referenced elsewhere.
Last but not least, some dedicated optimization can be performed more efficiently by the compiler (most importantly register ...
Contains case insensitive
...r.search(new RegExp("Ral", "i")) == -1) { ...
It looks more elegant then converting the whole string to lower case and it may be more efficient.
With toLowerCase() the code have two pass over the string, one pass is on the entire string to convert it to lower case and another is to look for the d...
How to center a Window in Java?
... answered Sep 28 '08 at 0:49
Andrew SwanAndrew Swan
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How to create a date object from string in javascript [duplicate]
Having this string 30/11/2011 . I want to convert it to date object.
8 Answers
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How can I save an image with PIL?
...port sys
import numpy
from PIL import Image
img = Image.open(sys.argv[1]).convert('L')
im = numpy.array(img)
fft_mag = numpy.abs(numpy.fft.fftshift(numpy.fft.fft2(im)))
visual = numpy.log(fft_mag)
visual = (visual - visual.min()) / (visual.max() - visual.min())
result = Image.fromarray((visual *...
What are C++ functors and their uses?
...about functors in C++. Can someone give me an overview as to what they are and in what cases they would be useful?
14 Answe...
How to delete a property from Google Analytics
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UPDATE/EDIT – December 5, 2014 : Converted this to community wiki… feel invited to edit and update.
UPDATE/EDIT – AUGUST 1, 2014
Google has done it again… they changed the design. But they also made things a bit simpler and more logic. Go to Admin...