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Why is transposing a matrix of 512x512 much slower than transposing a matrix of 513x513?
After conducting some experiments on square matrices of different sizes, a pattern came up. Invariably, transposing a matrix of size 2^n is slower than transposing one of size 2^n+1 . For small values of n , the difference is not major.
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How do I find if a string starts with another string in Ruby?
What the best way to find if a string starts with another in Ruby (without rails)?
4 Answers
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UIView frame, bounds and center
I would like to know how to use these properties in the right manner.
6 Answers
6
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Pandas: create two new columns in a dataframe with values calculated from a pre-existing column
I am working with the pandas library and I want to add two new columns to a dataframe df with n columns (n > 0).
These new columns result from the application of a function to one of the columns in the dataframe.
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Datetime - Get next tuesday
How can I get the date of next Tuesday?
10 Answers
10
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Does the ternary operator exist in R?
As the question asks, is there a control sequence in R similar to C's ternary operator ? If so, how do you use it? Thanks!
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\d is less efficient than [0-9]
I made a comment yesterday on an answer where someone had used [0123456789] in a regular expression rather than [0-9] or \d . I said it was probably more efficient to use a range or digit specifier than a character set.
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Is it possible to use raw SQL within a Spring Repository
I need to use raw SQL within a Spring Data Repository, is this possible? Everything I see around @Query is always entity based.
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ViewPager.setOffscreenPageLimit(0) doesn't work as expected
The fragments I use in my ViewPager instance are quite resource intensive, so I'd only like to load one at a time. When I try the following:
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Reducing the space between sections of the UITableView
Is there a way to reduce the space between two sections of a UITableView? There are about 15 pixels between every single section I have. I did already try to return 0 for -tableView:heightForFooterInSection: and -tableView:heightForHeaderInSection: but that doesn't change anything.
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