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Finding ALL duplicate rows, including “elements with smaller subscripts”
R's duplicated returns a vector showing whether each element of a vector or data frame is a duplicate of an element with a smaller subscript. So if rows 3, 4, and 5 of a 5-row data frame are the same, duplicated will give me the vector
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How to Vertical align elements in a div?
...with two images and an h1 . All of them need to be vertically aligned within the div, next to each other.
29 Answers
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How to test an Internet connection with bash?
How can an internet connection be tested without pinging some website?
I mean, what if there is a connection but the site is down? Is there a check for a connection with the world?
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How do you remove all the options of a select box and then add one option and select it with jQuery?
Using core jQuery, how do you remove all the options of a select box, then add one option and select it?
24 Answers
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JavaScript data formatting/pretty printer
I'm trying to find a way to pretty print a JavaScript data structure in a human-readable form for debugging.
15 Answers
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How to add 'ON DELETE CASCADE' in ALTER TABLE statement
I have a foreign key constraint in my table, I want to add ON DELETE CASCADE to it.
9 Answers
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Stop caching for PHP 5.5.3 in MAMP
Installed MAMP on a new Macbook with PHP 5.5.3.
9 Answers
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What does .SD stand for in data.table in R
.SD looks useful but I do not really know what I am doing with it. What does it stand for? Why is there a preceding period (full stop). What is happening when I use it?
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How to perform Unwind segue programmatically?
Using storyboard this is very easy. You just drag the action to "Exit". But how should I call it from my code?
10 Answers
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Relative frequencies / proportions with dplyr
Suppose I want to calculate the proportion of different values within each group. For example, using the mtcars data, how do I calculate the relative frequency of number of gears by am (automatic/manual) in one go with dplyr ?
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