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Scala Doubles, and Precision
...likely, I'd say. Anything involving grids or finance can require rounding and also performance.
– Rex Kerr
Jun 19 '12 at 20:33
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How to calculate cumulative normal distribution?
...f(-1.96)
0.024997895148220435
In other words, approximately 95% of the standard normal interval lies within two standard deviations, centered on a standard mean of zero.
If you need the inverse CDF:
>>> norm.ppf(norm.cdf(1.96))
array(1.9599999999999991)
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Infinite Recursion with Jackson JSON and Hibernate JPA issue
...ks to As Zammel AlaaEddine for pointing this out).
JsonManagedReference and JsonBackReference
Since Jackson 1.6 you can use two annotations to solve the infinite recursion problem without ignoring the getters/setters during serialization: @JsonManagedReference and @JsonBackReference.
Explanatio...
Why doesn't ruby support method overloading?
...od overloading can be achieved by declaring two methods with the same name and different signatures. These different signatures can be either,
Arguments with different data types, eg: method(int a, int b) vs method(String a, String b)
Variable number of arguments, eg: method(a) vs method(a, b)
W...
Extracting text OpenCV
I am trying to find the bounding boxes of text in an image and am currently using this approach:
10 Answers
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What are the big improvements between guava and apache equivalent libraries?
...
First of, as javamonkey79 explained, while Google Guava and Apache Commons do share similar features, they also both have functionality that is absent from their counterpart. Thus, limiting yourself to only one library might be unwise.
That being said, if I had to choose, I'd opt...
Java: Difference between PrintStream and PrintWriter
What is the difference between PrintStream and PrintWriter ? They have many methods in common due to which I often mix these two classes up. Moreover, I think we can use them for exactly the same things. But there has to be a difference, otherwise, there would have been only one class.
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How to atomically delete keys matching a pattern using Redis
...ing: As the Redis document says, because of performance maters, keys
command should not use for regular operations in production, this
command is intended for debugging and special operations. read
more
See the EVAL documentation.
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How to remove from a map while iterating it?
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The standard associative-container erase idiom:
for (auto it = m.cbegin(); it != m.cend() /* not hoisted */; /* no increment */)
{
if (must_delete)
{
m.erase(it++); // or "it = m.erase(it)" since C++11
}
else
{
...
What is the difference between packaged_task and async
...nces if you use a rather long function, such as
//! sleeps for one second and returns 1
auto sleep = [](){
std::this_thread::sleep_for(std::chrono::seconds(1));
return 1;
};
Packaged task
A packaged_task won't start on it's own, you have to invoke it:
std::packaged_task<int()> tas...