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Polymorphism in C++
... using the same notation x += 2 and the compiler produces:
type-specific CPU instructions
a result of the same type.
Overloading then seamlessly extends to user-defined types:
std::string x;
int y = 0;
x += 'c';
y += 'c';
Compiler-provided overloads for basic types is common in high-level (3...
How does the “this” keyword work?
...ript interpreter maintains as it evaluates JavaScript code, like a special CPU register which holds a reference to an object. The interpreter updates the ThisBinding whenever establishing an execution context in one of only three different cases:
1. Initial global execution context
This is the case ...
TLSF源码及算法介绍 - 开源 & Github - 清泛网 - 专注C/C++及内核技术
...操作系统的内存分配算法，时间复杂度 O(1)，在内存碎片问题上表现良好，可以将它看做是一个动态管理内存的内存池，提供分配及回收内存的方法，并能够进行内存碎片化整理。它的特点在于：
可以预期的分配执行时间，无...
Use CSS3 transitions with gradient backgrounds
...been some browser releases that supported transitions on gradients (e.g IE10. I tested gradient transitions in 2016 in IE and they seemed to work at the time, but my test code no longer works.)
Update: October 2018
Gradient transitions with un-prefixed new syntax [e.g. radial-gradient(...)]now conf...
xkcd style graphs in MATLAB
...nshot, and IMTRANSFORM to get a transformation.
%# define plot data
x = 1:0.1:10;
y1 = sin(x).*exp(-x/3) + 3;
y2 = 3*exp(-(x-7).^2/2) + 1;
%# plot
fh = figure('color','w');
hold on
plot(x,y1,'b','lineWidth',3);
plot(x,y2,'w','lineWidth',7);
plot(x,y2,'r','lineWidth',3);
xlim([0.95 10])
ylim([0 5]...
What is the best regular expression to check if a string is a valid URL?
...re in PCRE syntax.
For absolute IRIs (internationalized):
/^[a-z](?:[-a-z0-9\+\.])*:(?:\/\/(?:(?:%[0-9a-f][0-9a-f]|[-a-z0-9\._~\x{A0}-\x{D7FF}\x{F900}-\x{FDCF}\x{FDF0}-\x{FFEF}\x{10000}-\x{1FFFD}\x{20000}-\x{2FFFD}\x{30000}-\x{3FFFD}\x{40000}-\x{4FFFD}\x{50000}-\x{5FFFD}\x{60000}-\x{6FFFD}\x{70000...
How to change the order of DataFrame columns?
...ged as needed.
This is what you have now:
In [6]: df
Out[6]:
0 1 2 3 4 mean
0 0.445598 0.173835 0.343415 0.682252 0.582616 0.445543
1 0.881592 0.696942 0.702232 0.696724 0.373551 0.670208
2 0.662527 0.955193 0.131016 0.609548 0.8046...
Convert light frequency to RGB?
...
answered Sep 24 '09 at 15:47
Stephen MesaStephen Mesa
4,31333 gold badges2121 silver badges1616 bronze badges
...
Understanding the Use of ColorMatrix and ColorMatrixColorFilter to Modify a Drawable's Hue
...
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cartesian product in pandas
...f1, df2,on='key')[['col1', 'col2', 'col3']]
Output:
col1 col2 col3
0 1 3 5
1 1 3 6
2 2 4 5
3 2 4 6
See here for the documentation: http://pandas.pydata.org/pandas-docs/stable/merging.html#brief-primer-on-merge-methods-relational-algebra
...