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How can I get a list of locally installed Python modules?
I would like to get a list of Python modules, which are in my Python installation (UNIX server).
30 Answers
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On localhost, how do I pick a free port number?
I'm trying to play with inter-process communication and since I could not figure out how to use named pipes under Windows I thought I'll use network sockets. Everything happens locally. The server is able to launch slaves in a separate process and listens on some port. The slaves do their work and s...
Best way to test if a row exists in a MySQL table
I'm trying to find out if a row exists in a table. Using MySQL, is it better to do a query like this:
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Write bytes to file
I have a hexadecimal string (e.g 0CFE9E69271557822FE715A8B3E564BE ) and I want to write it to a file as bytes. For example,
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Version number comparison in Python
I want to write a cmp -like function which compares two version numbers and returns -1 , 0 , or 1 based on their compared valuses.
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Understanding exactly when a data.table is a reference to (vs a copy of) another data.table
I'm having a little trouble understanding the pass-by-reference properties of data.table . Some operations seem to 'break' the reference, and I'd like to understand exactly what's happening.
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Difference between variable declaration syntaxes in Javascript (including global variables)?
Is there any difference between declaring a variable:
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Replacing NAs with latest non-NA value
In a data.frame (or data.table), I would like to "fill forward" NAs with the closest previous non-NA value. A simple example, using vectors (instead of a data.frame ) is the following:
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LINGO使用指南 - 更多技术 - 清泛网 - 专注C/C++及内核技术
...将被包含在主窗口之下。在主窗口内的标题为LINGO Model – LINGO1的窗口是LINGO的默认模型窗口，建立的模型都都要在该窗口内编码实现。下面举两个例子。
例1.1 如何在LINGO中求解如下的LP问题：
在模型窗口中输入如下代码：...
Does Java support default parameter values?
I came across some Java code that had the following structure:
24 Answers
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