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Best way to find if an item is in a JavaScript array? [duplicate]
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As of ECMAScript 2016 you can use includes()
arr.includes(obj);
If you want to support IE or other older browsers:
function include(arr,obj) {
return (arr.indexOf(obj) != -1);
}
EDIT:
This will not work on IE6, 7 or 8 though. The bes...
Finding ALL duplicate rows, including “elements with smaller subscripts”
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130
duplicated has a fromLast argument. The "Example" section of ?duplicated shows you how to use...
Changing the “tick frequency” on x or y axis in matplotlib?
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11 Answers
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How to iterate over arguments in a Bash script
...hat I'd like to make a shell/bash script of. I can write it in terms of $1 easily:
8 Answers
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Operation on every pair of element in a list
... module. It does exactly what you describe.
import itertools
my_list = [1,2,3,4]
for pair in itertools.product(my_list, repeat=2):
foo(*pair)
This is equivalent to:
my_list = [1,2,3,4]
for x in my_list:
for y in my_list:
foo(x, y)
Edit: There are two very similar functions as...
Remove the last character in a string in T-SQL?
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21 Answers
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How to succinctly write a formula with many variables from a data frame?
...in a formula to mean all the variables, it is the . identifier.
y <- c(1,4,6)
d <- data.frame(y = y, x1 = c(4,-1,3), x2 = c(3,9,8), x3 = c(4,-4,-2))
mod <- lm(y ~ ., data = d)
You can also do things like this, to use all variables but one (in this case x3 is excluded):
mod <- lm(y ~ ...
SQL MAX of multiple columns?
How do you return 1 value per row of the max of several columns:
22 Answers
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Error: “dictionary update sequence element #0 has length 1; 2 is required” on Django 1.4
I have an error message on django 1.4:
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