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How do I check if a variable exists in a list in BASH
...ho 'no'
or create a function:
contains() {
[[ $1 =~ (^|[[:space:]])$2($|[[:space:]]) ]] && exit(0) || exit(1)
}
to use it:
contains aList anItem
echo $? # 0： match, 1: failed
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How to get an object's properties in JavaScript / jQuery?
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142
You can look up an object's keys and values by either invoking JavaScript's native for in loop:
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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...
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....
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 to convert Milliseconds to “X mins, x seconds” in Java?
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27 Answers
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How do you do a ‘Pause’ with PowerShell 2.0?
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edited Dec 27 '14 at 14:54
Peter Mortensen
26.5k2121 gold badges9292 silver badges122122 bronze badges
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How to properly match varargs in Mockito
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238
Mockito 1.8.1 introduced anyVararg() matcher:
when(a.b(anyInt(), anyInt(), Matchers.<Strin...
Is Redis just a cache?
... 1
(integer) 1
$ HMSET question:1 title "Is Redis just a cache?" asked_by 12 votes 0
OK
$ HINCRBY unique_ids answer 1
(integer) 1
$ HMSET answer:1 question_id 1 answer_text "No, its a lot more" answered_by 15 votes 1
OK
Handling Up Votes
Now, everytime someone upvotes a question or an answer, yo...