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C++ preprocessor __VA_ARGS__ number of arguments
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90
This is actually compiler dependent, and not supported by any standard.
Here however you have a...
Why does Decimal.Divide(int, int) work, but not (int / int)?
How come dividing two 32 bit int numbers as ( int / int ) returns to me 0 , but if I use Decimal.Divide() I get the correct answer? I'm by no means a c# guy.
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CSS filter: make color image with transparency white
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You can use
filter: brightness(0) invert(1);
html {
background: red;
}
p {
float: left;
max-width: 50%;
text-align: center;
}
img {
display: block;
max-width: 100%;
}
.filter {
-webkit-filter: brightness(0) invert(1);
fi...
Relative frequencies / proportions with dplyr
...n = n()) %>%
mutate(freq = n / sum(n))
# am gear n freq
# 1 0 3 15 0.7894737
# 2 0 4 4 0.2105263
# 3 1 4 8 0.6153846
# 4 1 5 5 0.3846154
From the dplyr vignette:
When you group by multiple variables, each summary peels off one level of the grouping. That makes ...
Using jquery to get element's position relative to viewport
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edited Apr 17 '13 at 9:50
Pang
8,2181717 gold badges7373 silver badges111111 bronze badges
answered Oc...
Regex how to match an optional character
...e letter optional. {1} is redundant. (Of course you could also write [A-Z]{0,1} which would mean the same, but that's what the ? is there for.)
You could improve your regex to
^([0-9]{5})+\s+([A-Z]?)\s+([A-Z])([0-9]{3})([0-9]{3})([A-Z]{3})([A-Z]{3})\s+([A-Z])[0-9]{3}([0-9]{4})([0-9]{2})([0-9]{2})
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Local dependency in package.json
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620
npm >= 2.0.0
This feature was implemented in the version 2.0.0 of npm. Example:
{
"name":...
Best way to make Java's modulus behave like it should with negative numbers?
...the negative values of a, since (a % b) is a negative value between -b and 0, (a % b + b) is necessarily lower than b and positive. The last modulo is there in case a was positive to begin with, since if a is positive (a % b + b) would become larger than b. Therefore, (a % b + b) % b turns it into s...
How to determine if a point is in a 2D triangle? [closed]
... d2 = sign(pt, v2, v3);
d3 = sign(pt, v3, v1);
has_neg = (d1 < 0) || (d2 < 0) || (d3 < 0);
has_pos = (d1 > 0) || (d2 > 0) || (d3 > 0);
return !(has_neg && has_pos);
}
share
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What is the most efficient/elegant way to parse a flat table into a tree?
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Now that MySQL 8.0 supports recursive queries, we can say that all popular SQL databases support recursive queries in standard syntax.
WITH RECURSIVE MyTree AS (
SELECT * FROM MyTable WHERE ParentId IS NULL
UNION ALL
SELECT m.* F...