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Find integer index of rows with NaN in pandas dataframe
...MultiIndex that you can use to index back into df, e.g.:
df['a'].ix[index[0]]
>>> 1.452354
For the integer index:
df_index = df.index.values.tolist()
[df_index.index(i) for i in index]
>>> [3, 6]
share...
std::vector performance regression when enabling C++11
...ck(Item());)
$ g++ -std=c++11 -O3 -flto regr.cpp && perf stat -r 10 ./a.out
Performance counter stats for './a.out' (10 runs):
35.426793 task-clock # 0.986 CPUs utilized ( +- 1.75% )
4 context-switches # 0.116 K/sec ...
How does Dijkstra's Algorithm and A-Star compare?
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answered Aug 26 '09 at 5:18
leizleiz
3,63622 gold badges2020 silver badges1616 bronze badges
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What is the best way to compute trending topics or tags?
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104
This problem calls for a z-score or standard score, which will take into account the historical...
Why does Math.round(0.49999999999999994) return 1?
...n see that each value slightly less than .5 is rounded down, except for 0.5 .
5 Answers
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Why does GCC generate 15-20% faster code if I optimize for size instead of speed?
I first noticed in 2009 that GCC (at least on my projects and on my machines) have the tendency to generate noticeably faster code if I optimize for size ( -Os ) instead of speed ( -O2 or -O3 ), and I have been wondering ever since why.
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How to print a number with commas as thousands separators in JavaScript
... ====>"} ${x} => ${result}`);
return pass;
}
let failures = 0;
failures += !test(0, "0");
failures += !test(100, "100");
failures += !test(1000, "1,000");
failures += !test(10000, "10,000");
failures += !test(100000, "100,000");
failures += !test(1000000, "...
Replace all non Alpha Numeric characters, New Lines, and multiple White Space with one Space
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Be aware, that \W leaves the underscore. A short equivalent for [^a-zA-Z0-9] would be [\W_]
text.replace(/[\W_]+/g," ");
\W is the negation of shorthand \w for [A-Za-z0-9_] word characters (including the underscore)
Example at regex101.com
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How to scale down a range of numbers with a known min and max value
...l. I want the height and width of each ellipse to be in a range of say 1-30. I have methods that find the minimum and maximum values from my data set, but I won't have the min and max until runtime. Is there an easy way to do this?
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Simple C example of doing an HTTP POST and consuming the response
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+50
A message has a header part and a message body separated by a blank line. The blank line is ALWAYS needed even if there is no message...