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Bitwise operation and usage
...wise it's 0.
OR is 1 if one or both of its inputs are 1, otherwise it's 0.
XOR is 1 only if exactly one of its inputs are 1, otherwise it's 0.
NOT is 1 only if its input is 0, otherwise it's 0.
These can often be best shown as truth tables. Input possibilities are on the top and left, the resulta...
How can I handle R CMD check “no visible binding for global variable” notes when my ggplot2 syntax i
...instead of aes? This should work, although I haven't tried it:
aes_string(x = 'x.values', y = 'y.values')
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Does it make sense to use “as” instead of a cast even if there is no null check? [closed]
In development blogs, online code examples and (recently) even a book, I keep stumbling about code like this:
13 Answers
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How do I draw a grid onto a plot in Python?
...ot using pylab in Python and now I would like to superimpose a grid of 10x10 onto the scatter plot. How do I do that?
5 A...
Why doesn't c++ have &&= or ||= for booleans?
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The reason is that b & 2 performs integer promotion such that the expression is then equivalent to static_cast<int>(b) & 2, which results in 0, which is then converted back into a bool. So it’s true that the existence of an operator &&= would improve type safety.
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Convert nullable bool? to bool
...will represent. If null should be false, you can do this:
bool newBool = x.HasValue ? x.Value : false;
Or:
bool newBool = x.HasValue && x.Value;
Or:
bool newBool = x ?? false;
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Structure padding and packing
... char gap_1[3]; /* -"-: for alignment of the whole struct in an array */
} x;
Packing, on the other hand prevents compiler from doing padding - this has to be explicitly requested - under GCC it's __attribute__((__packed__)), so the following:
struct __attribute__((__packed__)) mystruct_A {
c...
equals vs Arrays.equals in Java
..., i.e. is it the same array. As @alf points out it's not what most people expect.
Arrays.equals(array1, array2) compares the contents of the arrays.
Similarly array.toString() may not be very useful and you need to use Arrays.toString(array).
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How to install a specific JDK on Mac OS X?
I want to install a specific JDK (the latest for example). For this, I went to the JDK download homepage: http://java.sun.com/javase/downloads/index.jsp .
I looked for a Mac version, but I'm a bit surprised to only see downloadable versions for Linux, Windows and Solaris ...
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How do I use itertools.groupby()?
I haven't been able to find an understandable explanation of how to actually use Python's itertools.groupby() function. What I'm trying to do is this:
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