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Random number generation in C++11: how to generate, how does it work? [closed]
I recently came across new way to generate random numbers in C++11, but couldn't digest the papers that I read about it (what is that engine , maths term like distribution , "where all integers produced are equally likely ").
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How do you get the length of a list in the JSF expression language?
...length attributes, they won't implement getSize() or getLength() which JSF and most other standards require, you can't do what you want.
There's a couple ways to do this.
One: add a function to your Bean that returns the length:
In class MyBean:
public int getSomelistLength() { return this.somel...
Get file name and extension in Ruby
I'm working on a program to download a video from YouTube, convert it to MP3 and create a directory structure for the files.
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How to group dataframe rows into list in pandas groupby?
..., x, y]
C [6] [z]
To group-listify a single column only, convert the groupby to a SeriesGroupBy object, then call SeriesGroupBy.agg. Use,
df.groupby('a').agg({'b': list}) # 4.42 ms
df.groupby('a')['b'].agg(list) # 2.76 ms - faster
a
A [1, 2]
B [5, 5, 4]
C [...
How costly is .NET reflection?
...rs using your application (if it's web) and it may add up just as if you'd convert million items. If particular method is 100-times slower it will be that much slower on small and big sets. Slower is slower.
– Robert Koritnik
Jul 26 '12 at 13:17
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How do you make a deep copy of an object?
... final or can't be modified, extend the class and implement serializable.
Convert your class to a stream of bytes:
ByteArrayOutputStream bos = new ByteArrayOutputStream();
ObjectOutputStream oos = new ObjectOutputStream(bos);
oos.writeObject(object);
oos.flush();
oos.close();
bos.close();
byte[] b...
How to use GROUP_CONCAT in a CONCAT in MySQL
...SEPARATOR ',') AS result
FROM test GROUP BY id
you must use cast or convert, otherwise will be return BLOB
result is
id Column
1 A:4,A:5,B:8
2 C:9
you have to handle result once again by program such as python or java
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How to check whether a given string is valid JSON in Java
...is solution not only validates, but parses (and stores) the whole json. It converts numbers to Integer/Long/Double etc. This is more than just syntax check, it stores whole json in the memory. This might be significant for intensive loads. If better solution for syntax check exists?
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Get all directories within directory nodejs
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@nicksweet Can you convert this to JS?
– mikemaccana
Feb 5 '15 at 13:09
1
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How do I do a multi-line string in node.js?
...for me, is the same thing wrong with Groovy last I checked. When a file is converted from .coffee to .js, the line numbers are jumbled. I have not tried CoffeeScript, but when I tried Groovy, I found it quite difficult to debug without getting the generated .java files.
– Bryan...