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Can dplyr package be used for conditional mutating?
Can the mutate be used when the mutation is conditional (depending on the values of certain column values)?
5 Answers
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Concatenate two slices in Go
I'm trying to combine the slice [1, 2] and the slice [3, 4] . How can I do this in Go?
7 Answers
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How do I extract a sub-hash from a hash?
I have a hash:
16 Answers
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What's wrong with nullable columns in composite primary keys?
ORACLE does not permit NULL values in any of the columns that comprise a primary key. It appears that the same is true of most other "enterprise-level" systems.
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Why does C++ require a user-provided default constructor to default-construct a const object?
The C++ standard (section 8.5) says:
5 Answers
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Immutable vs Mutable types
I'm confused on what an immutable type is. I know the float object is considered to be immutable, with this type of example from my book:
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Difference between Python's Generators and Iterators
What is the difference between iterators and generators? Some examples for when you would use each case would be helpful.
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What is a lambda (function)?
For a person without a comp-sci background, what is a lambda in the world of Computer Science?
23 Answers
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Defeating a Poker Bot
There is a new Open Source poker bot called PokerPirate . I am interested in any creative ways in which a web application could detect/thwart/defeat a poker bot. (This is a purely academic discussion, in the same spirit that PokerPirate was written.)
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Circular dependency in Spring
How does Spring resolve this: bean A is dependent on bean B, and bean B on bean A.
12 Answers
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