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Modifying a subset of rows in a pandas dataframe
...
Use .loc for label based indexing:
df.loc[df.A==0, 'B'] = np.nan
The df.A==0 expression creates a boolean series that indexes the rows, 'B' selects the column. You can also use this to transform a subset of a column, e.g.:
df.loc[df.A==0, '...
Generating statistics from Git repository [closed]
...ring Gnuplot for graphs, there is also
gitstat (SourceForge) project (web-based git statistics interface), written in PHP and Perl,
Git Statistics, aka gitstats (metrics framework designed to gather statistics on git repositories), written in Python, result of git-statistics project at Google Summe...
Install tkinter for Python
... from sources, but this is usually not the best idea with a binary package-based distro you're apparently running.
It's safer to apt-get install python-tk on your machine(s).
(Works on Debian-derived distributions like for Ubuntu; refer to your package manager and package list on other distribution...
STL中map容器使用自定义key类型报错详解 - C/C++ - 清泛网 - 专注C/C++及内核技术
...l(143) : error C2784: “bool std::operator <(const std::_Revranit<_RanIt,_Base> &,const std::_Revranit<_RanIt2,_Base2> &)”: 无法从“const a”为“const std::_Revranit<_RanIt,_Base> &”推导 模板 参数
1> f:\vs2008\vc\include\xutility(2046) : 参见“std::operator <”的声...
Converting pixels to dp
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@MuhammadBabar This is because 160 dpi (mdpi) is the baseline desity from which other densities are calculated. hdpi for instance is considered to be 1.5x the density of mdpi which is really just another way of saying 240 dpi. See Zsolt Safrany's answer below for all densities....
Prefer composition over inheritance?
...this object be usable by code which expects objects of (what would be) the base type". If the answer is yes, the object must inherit. If no, then it probably should not. If I had my druthers, languages would provide a keyword to refer to "this class", and provide a means of defining a class which...
JSONP with ASP.NET Web API
...er.Write(callback + "(");
writer.Flush();
base.WriteToStreamAsync(type, value, stream, content, transportContext).Wait();
writer.Write(")");
writer.Flush();
});
}
else
{
return base.Writ...
AngularJS - How can I do a redirect with a full page load?
...s.org/">link</a>
Links starting with '/' that lead to a different base path when base is defined
Example: <a href="/not-my-base/link">link</a>
Using javascript:
The $location service allows you to change only the URL; it does not allow you to reload the page. When you need to...
How can I create a directly-executable cross-platform GUI app using Python?
...re are many, but the most popular that I've seen in wild are:
Tkinter - based on Tk GUI toolkit (de-facto standard GUI library for python, free for commercial projects)
WxPython - based on WxWidgets (popular, free for commercial projects)
Qt using the PyQt bindings or Qt for Python. The former is...
What's the best three-way merge tool? [closed]
...rial and others support three-way merges (combining mine, theirs, and the "base" revision) and support graphical tools to resolve conflicts.
...