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How to debug Apache mod_rewrite
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284
One trick is to turn on the rewrite log. To turn it on,try these lines in your apache main con...
Maximum on http header values?
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325
No, HTTP does not define any limit. However most web servers do limit size of headers they acce...
MySQL, update multiple tables with one query
..., we increase the number of books in a particular order with Order.ID = 1002 in Orders table then we also need to reduce that the total number of books available in our stock by the same number in Books table.
UPDATE Books, Orders
SET Orders.Quantity = Orders.Quantity + 2,
Books.InStock = Books....
Best way of returning a random boolean value
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245
A declarative snippet using Array#sample:
random_boolean = [true, false].sample
...
What are the pros and cons of the SVN plugins for Eclipse, Subclipse and Subversive? [closed]
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32 Answers
32
Active
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How to extend an existing JavaScript array with another array, without creating a new array
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Arsen Khachaturyan
5,90933 gold badges3232 silver badges3434 bronze badges
answered Sep 3 '09 at 15:27
DzinXDzinX
43....
Remove duplicated rows using dplyr
...tion for this purpose.
Original answer below:
library(dplyr)
set.seed(123)
df <- data.frame(
x = sample(0:1, 10, replace = T),
y = sample(0:1, 10, replace = T),
z = 1:10
)
One approach would be to group, and then only keep the first row:
df %>% group_by(x, y) %>% filter(row_num...
Function for Factorial in Python
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192
Easiest way is to use math.factorial (available in Python 2.6 and above):
import math
math.fact...
Javascript reduce() on Object
...plementation with that in mind:
const add = {
a: {value:1},
b: {value:2},
c: {value:3}
}
const total = Object.values(add).reduce((t, {value}) => t + value, 0)
console.log(total) // 6
or simply:
const add = {
a: 1,
b: 2,
c: 3
}
const total = Object.values(add).reduce((t, n) =>...
How to split last commit into two in Git
...o that now it looks like this:
1
something
something else
something again
2
Now I decide that I want to split it into two, and I want the insertion of the
first line to be in the first commit, and the insertion of the last line to be
in the second commit.
First I go back to HEAD's parent, but I ...