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How to take column-slices of dataframe in pandas
I load some machine learning data from a CSV file. The first 2 columns are observations and the remaining columns are features.
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Google Maps API 3 - Custom marker color for default (dot) marker
I've seen lots of other questions similar to this ( here , here and here ), but they all have accepted answers that don't solve my problem. The best solution I have found to the problem is the StyledMarker library, which does let you define custom colours for markers, but I can't get it to use ...
Why is address zero used for the null pointer?
In C (or C++ for that matter), pointers are special if they have the value zero: I am adviced to set pointers to zero after freeing their memory, because it means freeing the pointer again isn't dangerous; when I call malloc it returns a pointer with the value zero if it can't get me memory; I use ...
Sample random rows in dataframe
I am struggling to find the appropriate function that would return a specified number of rows picked up randomly without replacement from a data frame in R language? Can anyone help me out?
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Find XOR of all numbers in a given range
You are given a large range [a,b] where 'a' and 'b' can be typically between 1 and 4,000,000,000 inclusive. You have to find out the XOR of all the numbers in the given range.
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What is the difference between Ruby 1.8 and Ruby 1.9
I'm not clear on the differences between the "current" version of Ruby (1.8) and the "new" version (1.9). Is there an "easy" or a "simple" explanation of the differences and why it is so different?
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How to initialize an array's length in JavaScript?
Most of the tutorials that I've read on arrays in JavaScript (including w3schools and devguru ) suggest that you can initialize an array with a certain length by passing an integer to the Array constructor using the var test = new Array(4); syntax.
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How do I convert a TimeSpan to a formatted string? [duplicate]
I have two DateTime vars, beginTime and endTime. I have gotten the difference of them by doing the following:
14 Answers
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Why do Lua arrays(tables) start at 1 instead of 0?
I don't understand the rationale behind the decision of this part of Lua. Why does indexing start at 1? I have read (as many others did) this great paper . It seems to me a strange corner of a language that is very pleasant to learn and program. Don't get me wrong, Lua is just great but there has t...
Remove outline from select box in FF
Is it possible to remove the dotted line surrounding a selected item in a select element?
12 Answers
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