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How to remove a key from Hash and get the remaining hash in Ruby/Rails?
... your five-minutes-of-editing are up, you can always copy, delete, modify, and repost a comment.
– iconoclast
May 13 at 23:17
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Dynamically select data frame columns using $ and a character value
I have a vector of different column names and I want to be able to loop over each of them to extract that column from a data.frame. For example, consider the data set mtcars and some variable names stored in a character vector cols . When I try to select a variable from mtcars using a dynamic s...
HTML table with fixed headers?
...isplay a long HTML table such that the column headers stay fixed on-screen and do not scroll with the table body. Think of the "freeze panes" effect in Microsoft Excel.
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Local and global temporary tables in SQL Server
What is the difference between local and global temporary tables in SQL Server?
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UnboundLocalError on local variable when reassigned after first use
The following code works as expected in both Python 2.5 and 3.0:
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Circle-Rectangle collision detection (intersection)
How can I tell whether a circle and a rectangle intersect in 2D Euclidean space? (i.e. classic 2D geometry)
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Which is faster : if (bool) or if(int)?
The above topic made me do some experiments with bool and int in if condition. So just out of curiosity I wrote this program:
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Simple explanation of MapReduce?
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Going all the way down to the basics for Map and Reduce.
Map is a function which "transforms" items in some kind of list to another kind of item and put them back in the same kind of list.
suppose I have a list of numbers: [1,2,3] and I want to double every number, ...
Making WPF applications look Metro-styled, even in Windows 7? (Window Chrome / Theming / Theme)
I like the window chrome on the new Office Suite and Visual Studio:
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Reorder levels of a factor without changing order of values
I have data frame with some numerical variables and some categorical factor variables. The order of levels for those factors is not the way I want them to be.
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