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What is a clean, pythonic way to have multiple constructors in Python?
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Actually None is much better for "magic" values:
class Cheese():
def __init__(self, num_holes = None):
if num_holes is None:
...
Now if you want complete freedom of adding more parameters:
class Cheese...
Elastic Search: how to see the indexed data
...lore your ElasticSearch cluster is to use elasticsearch-head.
You can install it by doing:
cd elasticsearch/
./bin/plugin -install mobz/elasticsearch-head
Then (assuming ElasticSearch is already running on your local machine), open a browser window to:
http://localhost:9200/_plugin/head/
Alte...
What is the most effective way for float and double comparison?
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Be extremely careful using any of the other suggestions. It all depends on context.
I have spent a long time tracing a bugs in a system that presumed a==b if |a-b|<epsilon. The underlying problems were:
The implicit presumption in an algorithm that if a==b and b==c then a==c.
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How do I migrate a model out of one django app and into a new one?
... that one of these models should be in a separate app. I do have south installed for migrations, but I don't think this is something it can handle automatically. How can I migrate one of the models out of the old app into a new one?
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Change all files and folders permissions of a directory to 644/755
How would I change all files to 644 and all folders to 755 using chmod from the linux command prompt? (Terminal)
8 Answ...
std::function and std::bind: what are they, and when should they be used?
...nd to get g:
auto g = bind(f, _1, 4, _2);
This is more concise than actually writing a functor class to do it.
There are further examples in the article you link to. You generally use it when you need to pass a functor to some algorithm. You have a function or functor that almost does the job yo...
Is there a TRY CATCH command in Bash
... writing a shell script and need to check that a terminal app has been installed. I want to use a TRY/CATCH command to do this unless there is a neater way.
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Weighted random numbers
...a weighted random numbers. I'm currently just banging my head against the wall and cannot figure this out.
7 Answers
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How do I find where an exception was thrown in C++?
I have a program that throws an uncaught exception somewhere. All I get is a report of an exception being thrown, and no information as to where it was thrown. It seems illogical for a program compiled to contain debug symbols not to notify me of where in my code an exception was generated.
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Odd behavior when Java converts int to byte?
...+ unsignedByte);
Would print out: "Signed: -1 Unsigned: 255"
What's actually happening here?
We are using bitwise AND to mask all of the extraneous sign bits (the 1's to the left of the least significant 8 bits.)
When an int is converted into a byte, Java chops-off the left-most 24 bits
111111...