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What are bitwise operators?
...t's own bit in a bitset (byte, short, int, or long). For example:
Read: 00000001
Write: 00000010
So if you want to pass read AND write, you would pass (READ | WRITE) which then combines the two into
00000011
Which then can be decrypted on the other end like:
if ((flag & Read) != 0) { /...
How does Dijkstra's Algorithm and A-Star compare?
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answered Aug 26 '09 at 5:18
leizleiz
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xkcd style graphs in MATLAB
...nshot, and IMTRANSFORM to get a transformation.
%# define plot data
x = 1:0.1:10;
y1 = sin(x).*exp(-x/3) + 3;
y2 = 3*exp(-(x-7).^2/2) + 1;
%# plot
fh = figure('color','w');
hold on
plot(x,y1,'b','lineWidth',3);
plot(x,y2,'w','lineWidth',7);
plot(x,y2,'r','lineWidth',3);
xlim([0.95 10])
ylim([0 5]...
How to select rows from a DataFrame based on column values?
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10 Answers
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Why does ++[[]][+[]]+[+[]] return the string “10”?
This is valid and returns the string "10" in JavaScript ( more examples here ):
9 Answers
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Find MongoDB records where array field is not empty
... the key, you can use:
ME.find({ pictures: { $exists: true, $not: {$size: 0} } })
MongoDB don't use indexes if $size is involved, so here is a better solution:
ME.find({ pictures: { $exists: true, $ne: [] } })
Since MongoDB 2.6 release, you can compare with the operator $gt but could lead to u...
Why does the expression 0 < 0 == 0 return False in Python?
... make range comparisons easy to express. It's much nicer to be able to say 0 &lt; x &lt;= 5 than to say (0 &lt; x) and (x &lt;= 5).
These are called chained comparisons. And that's a link to the documentation for them.
With the other cases you talk about, the parenthesis force one relational opera...
Most efficient way to create a zero filled JavaScript array?
...duces Array.prototype.fill. It can be used like this:
new Array(len).fill(0);
Not sure if it's fast, but I like it because it's short and self-describing.
It's still not in IE (check compatibility), but there's a polyfill available.
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Modifying a subset of rows in a pandas dataframe
...fy this DataFrame (or create a copy) so that B is always NaN whenever A is 0. How would I achieve that?
5 Answers
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What is the most pythonic way to check if an object is a number?
...cimal import Decimal
... from fractions import Fraction
... for n in [2, 2.0, Decimal('2.0'), complex(2, 0), Fraction(2, 1), '2']:
... print(f'{n!r:&gt;14} {isinstance(n, Number)}')
2 True
2.0 True
Decimal('2.0') True
(2+0j) True
Fraction(2, 1) True
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