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How do you add an array to another array in Ruby and not end up with a multi-dimensional result?
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edited Jul 23 '14 at 19:10
answered Nov 26 '09 at 5:09
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Microsoft.Jet.OLEDB.4.0' provider is not registered on the local machine
...T 3.5 in a 32 bit Windows 2008 server. When deployed the application in a 64 bit server it shows the error "Microsoft.Jet.OLEDB.4.0' provider is not registered on the local machine ".
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How to easily truncate an array with JavaScript?
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There is a slice method
array.slice(0, 4);
Will return the first four elements.
Don't forget to assign it back to your variable if you want to discard the other values.
Note: This is just regular javascript, no need for jquery.
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Further understanding setRetainInstance(true)
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94
Ok, perhaps I was slightly too harsh on the Android documentation, because it does have some use...
How do I get the last four characters from a string in C#?
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423
mystring.Substring(Math.Max(0, mystring.Length - 4)); //how many lines is this?
If you're po...
How to execute a Ruby script in Terminal?
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edited Jul 14 '15 at 20:08
Vince
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a...
What's the difference between a Python “property” and “attribute”?
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Ethan FurmanEthan Furman
47.7k1414 gold badges113113 silver badges189189 bronze badges
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How to keep index when using pandas merge
...1 1 1
b 2 3 2
c 3 4 NaN
Note that for some left merge operations, you may end up with more rows than in a when there are multiple matches between a and b. In this case, you may need to drop duplicates.
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pandas GroupBy columns with NaN (missing) values
...ng the groupby (e.g. -1):
In [11]: df.fillna(-1)
Out[11]:
a b
0 1 4
1 2 -1
2 3 6
In [12]: df.fillna(-1).groupby('b').sum()
Out[12]:
a
b
-1 2
4 1
6 3
That said, this feels pretty awful hack... perhaps there should be an option to include NaN in groupby (see this github i...
Escape double quotes in parameter
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mousiomousio
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