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How to add item to the beginning of List?
...ssible to insert at the end of the list?
– Gary Henshall
Dec 11 '17 at 14:36
3
@GaryHenshall yes,...
Java: how can I split an ArrayList in multiple small ArrayLists?
...ist are reflected in this list, and vice-versa. The returned list supports all of the optional list operations supported by this list.
Example:
List<Integer> numbers = new ArrayList<Integer>(
Arrays.asList(5,3,1,2,9,5,0,7)
);
List<Integer> head = numbers.subList(0, 4);
List...
Can one do a for each loop in java in reverse order?
...
The Collections.reverse method actually returns a new list with the elements of the original list copied into it in reverse order, so this has O(n) performance with regards to the size of the original list.
As a more efficient solution, you could write a deco...
Why does X[Y] join of data.tables not allow a full outer join, or a left join?
...Y) does both ways at the same time. The number of rows of X[Y] and Y[X] usually differ, whereas the number of rows returned by merge(X,Y) and merge(Y,X) is the same.
BUT that misses the main point. Most tasks require something to be done on the
data after a join or merge. Why merge all the co...
JSON serialization of Google App Engine models
...
There is a small mistake in the code: Where you have "output[key] = to_dict(model)" it should be: "output[key] = to_dict(value)". Besides that it's perfect. Thanks!
– arikfr
Nov 7 '09 at 22:02
...
How to determine an interface{} value's “real” type?
... h4ck3rm1k3h4ck3rm1k3
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Why do some claim that Java's implementation of generics is bad?
I've occasionally heard that with generics, Java didn't get it right. (nearest reference, here )
13 Answers
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Pip freeze vs. pip list
...you are using a virtualenv, you can specify a requirements.txt file to install all the dependencies.
A typical usage:
$ pip install -r requirements.txt
The packages need to be in a specific format for pip to understand, which is
feedparser==5.1.3
wsgiref==0.1.2
django==1.4.2
...
That is the ...
iPhone Simulator suddenly started running very slow
...lator for a number of weeks and it has been running well up until now, but all of a sudden has begun running very slow both when loading content and animations. I have not made any changes to my code since I last tested it successfully.
...
Best way to randomize an array with .NET
...e: as used in my example, Random() is perfectly thread-safe, unless you're allowing the routine in which you randomize the array to be re-entered, in which case you'll need something like lock (MyRandomArray) anyway in order not to corrupt your data, which will protect rnd as well.
Also, it should b...