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Convert a list to a data frame
...hich in turn yields FALSE as its default.
Assuming your list of lists is called l:
df <- data.frame(matrix(unlist(l), nrow=length(l), byrow=T))
The above will convert all character columns to factors, to avoid this you can add a parameter to the data.frame() call:
df <- data.frame(matrix(unl...
What is the difference between == and Equals() for primitives in C#?
... == operator is defined as taking two ints (or shorts or longs).
When you call it with an int and a short, the compiler will implicitly convert the short to int and compare the resulting ints by value.
Other ways to make it work
Primitive types also have their own Equals() method that accepts the sa...
Count the items from a IEnumerable without iterating?
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I usually just grab List and IList out of habit. But especially if you want to implement them yourself ICollection is easier and also has the Count property. Thanks!
– Mendelt
Oct 3 '08 at 22...
convert ArrayList to JSONArray
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PurushothamPurushotham
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5
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How to remove leading and trailing whitespace in a MySQL field?
... answered Jul 28 '11 at 11:27
cwallenpoolecwallenpoole
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Getting the difference between two sets
...
Try this
test2.removeAll(test1);
Set#removeAll
Removes from this set all of its elements that are contained in the specified collection (optional operation). If the specified collection is also a set, this operation effectively modifies thi...
How to delay the .keyup() handler until the user stops typing?
...
I use this small function for the same purpose, executing a function after the user has stopped typing for a specified amount of time or in events that fire at a high rate, like resize:
function delay(callback, ms) {
var timer = 0;
...
:: (double colon) operator in Java 8
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Usually, one would call the reduce method using Math.max(int, int) as follows:
reduce(new IntBinaryOperator() {
int applyAsInt(int left, int right) {
return Math.max(left, right);
}
});
That requires a lot of ...
UICollectionView spacing margins
...ction?
– Crashalot
Jan 18 '16 at 17:32
@Crashalot - are you sure you don't mean minimumLineSpacing? i.e. every line of...
What should I do if the current ASP.NET session is null?
...ireRequestState runs before control is handed to your Page. So if you are calling other functionality, including static classes, from your page, you should be fine.
If you have some classes doing initialization logic during startup, for example on the Application_Start event or by using a static con...