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Scala: Abstract types vs generics
I was reading A Tour of Scala: Abstract Types . When is it better to use abstract types?
4 Answers
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How can I verify if one list is a subset of another?
I need to verify if a list is a subset of another - a boolean return is all I seek.
15 Answers
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Split delimited strings in a column and insert as new rows [duplicate]
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Here is another way of doing it..
df <- read.table(textConnection("1|a,b,c\n2|a,c\n3|b,d\n4|e,f"), header = F, sep = "|", stringsAsFactors = F)
df
## V1 V2
## 1 1 a,b,c
## 2 2 a,c
## 3 3 b,d
## 4 4 e,f
s <- strsplit(df$V2, split = ",")
data.frame(V1 = ...
Laravel 4 Eloquent Query Using WHERE with OR AND OR?
How do I say WHERE (a = 1 OR b =1 ) AND (c = 1 OR d = 1)
11 Answers
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Pandas conditional creation of a series/dataframe column
I have a dataframe along the lines of the below:
8 Answers
8
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Does Java support default parameter values?
... complicated. For other methods, renaming some cases or using a parameter object can help. This is when you have enough complexity that differentiating is difficult. A definite case is where you have to differentiate using the order of parameters, not just number and type.
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How to check command line parameter in “.bat” file?
My OS is Windows Vista. I need to have a ".bat" file where I need to check if user enters any command-line parameter or not. If does then if the parameter equals to -b then I will do something otherwise I will flag "Invalid input". If user does not enter any command-line parameter then I will d...
Multiple variables in a 'with' statement?
Is it possible to declare more than one variable using a with statement in Python?
6 Answers
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What is the difference between a deep copy and a shallow copy?
What is the difference between a deep copy and a shallow copy?
31 Answers
31
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What does the `forall` keyword in Haskell/GHC do?
I'm beginning to understand how the forall keyword is used in so-called "existential types" like this:
8 Answers
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