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Best way of returning a random boolean value
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245
A declarative snippet using Array#sample:
random_boolean = [true, false].sample
...
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....
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...
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....
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) =>...
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...
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 ...
Initializing a member array in constructor initializer
...tly to fire off list initialization
struct A {
int foo[3];
A():foo{1, 2, 3} { }
A():foo({1, 2, 3}) { } /* invalid */
};
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How do I trim a file extension from a String in Java?
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290
This is the sort of code that we shouldn't be doing ourselves. Use libraries for the mundane s...