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How is CountDownLatch used in Java Multithreading?
...d consider the non-reusability an advantage: you're sure that no one can reset it, or increase the count.
– ataulm
Mar 16 '15 at 9:38
3
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Check if Python Package is installed
What's a good way to check if a package is installed while within a Python script? I know it's easy from the interpreter, but I need to do it within a script.
...
multi-layer perceptron (MLP) architecture: criteria for choosing number of hidden layers and size of
... components] needed to capture 70-90% of the variance of the input data
set.
And yet the NN FAQ author calls these Rules "nonsense" (literally) because they: ignore the number of training instances, the noise in the targets (values of the response variables), and the complexity of the feature s...
Remove and Replace Printed items [duplicate]
I was wondering if it was possible to remove items you have printed in Python - not from the Python GUI, but from the command prompt.
e.g.
...
Difference between signed / unsigned char [duplicate]
...a couple of cases where it is not:
If, in the target platform's character set, any of the characters required by standard C would map to a code higher than the maximum `signed char`, then `char` must be unsigned.
If `char` and `short` are the same size, then `char` must be signed.
Part of the reas...
Many-to-many relationship with the same model in rails?
...connection.save!
=> true
Instead of creating the association and then setting the category separately, you can also just create a PostConnection and be done with it:
>> b.posts = []
=> []
>> PostConnection.create(
?> :post_a => b, :post_b => a,
?> :category =>...
how to exclude null values in array_agg like in string_agg using postgres?
If I use array_agg to collect names, I get my names separated by commas, but in case there is a null value, that null is also taken as a name in the aggregate. For example :
...
memcpy() vs memmove()
I am trying to understand the difference between memcpy() and memmove() , and I have read the text that memcpy() doesn't take care of the overlapping source and destination whereas memmove() does.
...
What is the point of a private pure virtual function?
...ves some more attention, in my opinion. The public interface consists of a set of overloaded non-virtual functions and those functions call non-public, non-overloaded virtual functions. As usual in the C++ world it is an idiom, it has a name and of course it is useful. The name is (surprise, surpris...
Hexadecimal To Decimal in Shell Script
...The error as reported appears when the variables are null (or empty):
$ unset var3 var4; var5=$(($var4-$var3))
bash: -: syntax error: operand expected (error token is "-")
That could happen because the value given to bc was incorrect. That might well be that bc needs UPPERcase values. It needs BF...