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Dynamically select data frame columns using $ and a character value
I have a vector of different column names and I want to be able to loop over each of them to extract that column from a data.frame. For example, consider the data set mtcars and some variable names stored in a character vector cols . When I try to select a variable from mtcars using a dynamic s...
Calling clojure from java
Most of the top google hits for "calling clojure from java" are outdated and recommend using clojure.lang.RT to compile the source code. Could you help with a clear explanation of how to call Clojure from Java assuming you have already built a jar from the Clojure project and included it in the cl...
Create instance of generic type whose constructor requires a parameter?
If BaseFruit has a constructor that accepts an int weight , can I instantiate a piece of fruit in a generic method like this?
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How to use Comparator in Java to sort
I learned how to use the comparable but I'm having difficulty with the Comparator. I am having a error in my code:
14 Answ...
What's the best name for a non-mutating “add” method on an immutable collection?
Sorry for the waffly title - if I could come up with a concise title, I wouldn't have to ask the question.
74 Answers
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Get the name of an object's type
Is there a JavaScript equivalent of Java 's class.getName() ?
20 Answers
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Is there a typical state machine implementation pattern?
We need to implement a simple state machine in C .
Is a standard switch statement the best way to go?
We have a current state (state) and a trigger for the transition.
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Finding the index of elements based on a condition using python list comprehension
The following Python code appears to be very long winded when coming from a Matlab background
5 Answers
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Python: Check if one dictionary is a subset of another larger dictionary
I'm trying to write a custom filter method that takes an arbitrary number of kwargs and returns a list containing the elements of a database-like list that contain those kwargs .
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What is the “Execute Around” idiom?
What is this "Execute Around" idiom (or similar) I've been hearing about?
Why might I use it, and why might I not want to use it?
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