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How do I change the working directory in Python?
cd is the shell command to change the working directory.
14 Answers
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How to throw an exception in C?
...tion (or other notification error form the CPU if there is)(How processor handles the case of division by zero).
Exceptions are defined in C++ and other languages though. Exception handling in C++ is specified in the C++ standard "S.15 Exception handling", there is no equivalent section in the C st...
If table exists drop table then create it, if it does not exist just create it
...ks for a list of tables or views! DROP TABLE IF EXISTS 'table1', 'table2'; and DROP VIEW IF EXISTS 'view1', 'view2'; PS- What witchcraft did you use to have `s in inline code!?
– Campbeln
Mar 3 '16 at 23:32
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What's the difference between dynamic (C# 4) and var?
...ing with C# v4, but I couldn't make out the difference between a "dynamic" and "var".
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Converting integer to string in Python
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There is not typecast and no type coercion in Python. You have to convert your variable in an explicit way.
To convert an object in string you use the str() function. It works with any object that has a method called __str__() defined. In fact
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Regex Named Groups in Java
It is my understanding that the java.regex package does not have support for named groups ( http://www.regular-expressions.info/named.html ) so can anyone point me towards a third-party library that does?
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How do I perform the SQL Join equivalent in MongoDB?
...t array field>
}
}
Of course Mongo is not a relational database, and the devs are being careful to recommend specific use cases for $lookup, but at least as of 3.2 doing join is now possible with MongoDB.
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Python unittest - opposite of assertRaises?
...r test must exit with a failure condition, not an error one. On the other hand, if in running the same code you would raise a KeyError, that would be an error, not a failure. In python - differently than some other languages - Exceptions are routinely used for control flow, this is why we have the e...
How do I remove all .pyc files from a project?
I've renamed some files in a fairly large project and want to remove the .pyc files they've left behind. I tried the bash script:
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What is the meaning of “… …” token? i.e. double ellipsis operator on parameter pack
...mma is purely optional; §8.3.5/4 does say
Where syntactically correct and where “...” is not part of an abstract-declarator, “, ...” is synonymous with “...”.
This is within an abstract-declarator, [edit] but Johannes makes a good point that they are referring to an abstract-decla...