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Find MongoDB records where array field is not empty
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How to merge 2 List and removing duplicate values from it in C#
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in the input sequences including
duplicates.
List<int> list1 = new List<int> { 1, 12, 12, 5};
List<int> list2 = new List<int> { 12, 5, 7, 9, 1 };
List<int> ulist = list1.Union(list2).ToList();
// ulist output : 1, 12, 5, 7, 9
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How can I get nth element from a list?
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156
Look here, the operator used is !!.
I.e. [1,2,3]!!1 gives you 2, since lists are 0-indexed.
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How to redirect stderr and stdout to different files in the same line in script?
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Just add them in one line command 2>> error 1>> output
However, note that >> is for appending if the file already has data. Whereas, > will overwrite any existing data in the file.
So, command 2> error 1> output if you do not want to append.
Ju...
Creating a new column based on if-elif-else condition
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140
To formalize some of the approaches laid out above:
Create a function that operates on the ro...
Order data frame rows according to vector with specific order
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Try match:
df <- data.frame(name=letters[1:4], value=c(rep(TRUE, 2), rep(FALSE, 2)))
target <- c("b", "c", "a", "d")
df[match(target, df$name),]
name value
2 b TRUE
3 c FALSE
1 a TRUE
4 d FALSE
It will work as long as your target contains exact...
How to get default gateway in Mac OSX
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191
You can try with:
route -n get default
It is not the same as GNU/Linux's route -n (or even ip...
Can mustache iterate a top-level array?
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169
You can do it like this...
Mustache.render('<ul>{{#.}}<li>{{.}}</li>{{/.}}&...
Overload constructor for Scala's Case Classes?
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190
Overloading constructors isn't special for case classes:
case class Foo(bar: Int, baz: Int) {...
Intersection of two lists in Bash
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291
comm -12 <(ls 1) <(ls 2)
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