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R: rJava package install failing
When installing rJava using the install.packages("rJava") command I get the following error:
16 Answers
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Force page scroll position to top at page refresh in HTML
... This is the correct answer. The jQuery solution does not work in all cases.
– Harry Stevens
Dec 5 '17 at 18:52
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No ConcurrentList in .Net 4.0?
...read-safe, limited subset of IList<T>: in particular, one that would allow an Add and provide random read-only access by index (but no Insert, RemoveAt, etc., and also no random write access).
This was the goal of my ConcurrentList<T> implementation. But when I tested its performance in...
What is a singleton in C#?
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A singleton is a class which only allows one instance of itself to be created - and gives simple, easy access to said instance. The singleton premise is a pattern across software development.
There is a C# implementation "Implementing the Singleton Pattern i...
How can I declare and define multiple variables in one line using C++?
I always though that if I declare these three variables that they will all have the value 0
10 Answers
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Replacing a 32-bit loop counter with 64-bit introduces crazy performance deviations with _mm_popcnt_
...AMD documents it and compilers don't expose it.)
(Yes, these instructions all run on the same execution unit).
This dependency doesn't just hold up the 4 popcnts from a single loop iteration. It can carry across loop iterations making it impossible for the processor to parallelize different loop...
How do I pass extra arguments to a Python decorator?
... it needs to return another function which is the actual decorator:
def my_decorator(param):
def actual_decorator(func):
print("Decorating function {}, with parameter {}".format(func.__name__, param))
return function_wrapper(func) # assume we defined a wrapper somewhere
ret...
Best way to handle list.index(might-not-exist) in python?
...thonic solution is to use only try/except and not the -1 sentinel value at all. I.E. you should rewrite otherfunction. On the other hand, if it ain't broke, ...
– Andrew Jaffe
Jan 25 '10 at 15:49
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Center Oversized Image in Div
...mething like this. This should center any huge element in the middle vertically and horizontally with respect to its parent no matter both of their sizes.
.parent {
position: relative;
overflow: hidden;
//optionally set height and width, it will depend on the rest of the styling used
}
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sys.argv[1] meaning in script
...more tutorial level.
For every invocation of Python, sys.argv is automatically a list of strings representing the arguments (as separated by spaces) on the command-line. The name comes from the C programming convention in which argv and argc represent the command line arguments.
You'll want to lea...