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How to replace NaN values by Zeroes in a column of a Pandas Dataframe?
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In [7]: df
Out[7]:
0 1
0 NaN NaN
1 -0.494375 0.570994
2 NaN NaN
3 1.876360 -0.229738
4 NaN NaN
In [8]: df.fillna(0)
Out[8]:
0 1
0 0.000000 0.000000
1 -0.494375 0.570994
2 0.000000 0.000000
3 1.876360 -0.229738
4 0...
Recreating a Dictionary from an IEnumerable
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330
If you're using .NET 3.5 or .NET 4, it's easy to create the dictionary using LINQ:
Dictionary...
Execute SQLite script
I start up sqlite3 version 3.7.7, unix 11.4.2 using this command:
5 Answers
5
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Curly braces in string in PHP
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echo "This works: {$arr['key']}";
// Works
echo "This works: {$arr[4][3]}";
// This is wrong for the same reason as $foo[bar] is wrong outside a string.
// In other words, it will still work, but only because PHP first looks for a
// constant named foo; an error of level E_NOTICE (undefined c...
MIME type warning in chrome for png images
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answered Feb 2 '11 at 19:39
Stefan MohrStefan Mohr
2,12822 gold badges2424 silver badges3535 bronze badges
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Does a const reference class member prolong the life of a temporary?
...ences prolong the lifespan.
The standard specifies such behavior in §8.5.3/5, [dcl.init.ref], the section on initializers of reference declarations. The reference in your example is bound to the constructor's argument n, and becomes invalid when the object n is bound to goes out of scope.
The lif...
Select by partial string from a pandas DataFrame
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GarrettGarrett
31.4k55 gold badges5151 silver badges4747 bronze badges
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what is the difference between GROUP BY and ORDER BY in sql
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CMeratCMerat
3,8692121 silver badges2525 bronze badges
13...
Setting Vim whitespace preferences by filetype
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tbitai
13311 silver badge55 bronze badges
answered Oct 13 '09 at 20:08
PeterPeter
108k...