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Java optional parameters
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varargs could do that (in a way). Other than that, all variables in the declaration of the method must be supplied. If you want a variable to be optional, you can overload the method using a signature which doesn't require the parameter.
private boolean defaultOptionalFlagValue = tru...
Append value to empty vector in R?
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Appending to an object in a for loop causes the entire object to be copied on every iteration, which causes a lot of people to say "R is slow", or "R loops should be avoided".
As BrodieG mentioned in the comments: it is much better to pre-al...
Replace a value in a data frame based on a conditional (`if`) statement
In the R data frame coded for below, I would like to replace all of the times that B
appears with b .
8 Answers
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Understanding how recursive functions work
...lains I have a very fundamental programming question which I have just not been able to grok yet. Filtering out all of the (extremely clever) "In order to understand recursion, you must first understand recursion." replies from various online threads I still am not quite getting it.
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How to sort an array of objects by multiple fields?
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A multi dimensional sorting method, based on this answer:
Update: Here is an "optimized" version. It does a lot more preprocessing and creates a comparison function for each sorting option beforehand. It might need more more memory (as it stores a function for...
Does the Java &= operator apply & or &&?
... T is the type of E1, except that E1 is evaluated only once.
So a &= b; is equivalent to a = a & b;.
(In some usages, the type-casting makes a difference to the result, but in this one b has to be boolean and the type-cast does nothing.)
And, for the record, a &&= b; is not valid...
Remove a HTML tag but keep the innerHtml
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$('b').contents().unwrap();
This selects all <b> elements, then uses .contents() to target the text content of the <b>, then .unwrap() to remove its parent <b> element.
For the greatest performance, always...
What is the Ruby (spaceship) operator?
What is the Ruby <=> (spaceship) operator? Is the operator implemented by any other languages?
6 Answers
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Get the cartesian product of a series of lists?
How can I get the Cartesian product (every possible combination of values) from a group of lists?
13 Answers
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How do you convert a byte array to a hexadecimal string, and vice versa?
How can you convert a byte array to a hexadecimal string, and vice versa?
45 Answers
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