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Label encoding across multiple columns in scikit-learn
I'm trying to use scikit-learn's LabelEncoder to encode a pandas DataFrame of string labels. As the dataframe has many (50+) columns, I want to avoid creating a LabelEncoder object for each column; I'd rather just have one big LabelEncoder objects that works across all my columns of data. ...
Confusion between factor levels and factor labels
There seems to be a difference between levels and labels of a factor in R.
Up to now, I always thought that levels were the 'real' name of factor levels, and labels were the names used for output (such as tables and plots). Obviously, this is not the case, as the following example shows:
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Retina displays, high-res background images
...wer, here is the retina detection query I tend to use:
@media
only screen and (-webkit-min-device-pixel-ratio: 2),
only screen and ( min--moz-device-pixel-ratio: 2),
only screen and ( -o-min-device-pixel-ratio: 2/1),
only screen and ( min-device-pixel-ratio: 2),
only screen and ( ...
How to enable MySQL Query Log?
...he MySQL function that logs each SQL query statement received from clients and the time that query statement has submitted?
Can I do that in phpmyadmin or NaviCat?
How do I analyse the log?
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Difference between “and” and && in Ruby?
What is the difference between the && and and operators in Ruby?
7 Answers
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What is the rationale for fread/fwrite taking size and count as arguments?
We had a discussion here at work regarding why fread and fwrite take a size per member and count and return the number of members read/written rather than just taking a buffer and size. The only use for it we could come up with is if you want to read/write an array of structs which aren't evenly div...
Image Segmentation using Mean Shift explained
Could anyone please help me understand how Mean Shift segmentation actually works?
2 Answers
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What is the difference between range and xrange functions in Python 2.X?
Apparently xrange is faster but I have no idea why it's faster (and no proof besides the anecdotal so far that it is faster) or what besides that is different about
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The located assembly's manifest definition does not match the assembly reference
...un some unit tests in a C# Windows Forms application (Visual Studio 2005), and I get the following error:
53 Answers
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How to search by key=>value in a multidimensional array in PHP
..._r takes its fourth parameter by reference rather than by value; the ampersand & is crucial.
FYI: If you have an older version of PHP then you have to specify the pass-by-reference part in the call to search_r rather than in its declaration. That is, the last line becomes search_r($subarray, $k...