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How do I delete rows in a data frame?
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The key idea is you form a set of the rows you want to remove, and keep the complement of that set.
In R, the complement of a set is given by the '-' operator.
So, assuming the data.frame is called myData:
myData[-c(2, 4, 6), ] # notice the -
Of course, don't forget to "reassign" ...
Check whether number is even or odd
...r is even or odd? I've been wanting to figure this out for a long time now and haven't gotten anywhere.
16 Answers
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What is the difference between “pom” type dependency with scope “import” and without “import”?
...n then reference these dependencies in the dependency section of your POM (and all of its child POMs) without having to include a version etc.
However if in your POM you simply define a normal dependency to other-pom-artifact-id then all dependencies from the dependency section of the other-pom-art...
API pagination best practices
I'd love some some help handling a strange edge case with a paginated API I'm building.
11 Answers
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Vim: Creating parent directories on save
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augroup BWCCreateDir
autocmd!
autocmd BufWritePre * if expand("<afile>")!~#'^\w\+:/' && !isdirectory(expand("%:h")) | execute "silent! !mkdir -p ".shellescape(expand('%:h'), 1) | redraw! | endif
augroup END
Note the conditions: expand("<afile>")!~#'^\w\+:/' wil...
How to create a trie in Python
I'm interested in tries and DAWGs (direct acyclic word graph) and I've been reading a lot about them but I don't understand what should the output trie or DAWG file look like.
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How do I declare a 2d array in C++ using new?
... rowCount; ++i)
a[i] = new int[colCount];
The above, for colCount= 5 and rowCount = 4, would produce the following:
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vertical align middle in
I want to keep the height of #abc div at 50px and text to align vertically in the middle of the div .
10 Answers
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Create SQL script that create database and tables
I have a SQL database and tables that I would like to replicate in another SQL Server. I would like to create a SQL script that creates the database and tables in a single script.
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Parse an HTML string with JS
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Create a dummy DOM element and add the string to it. Then, you can manipulate it like any DOM element.
var el = document.createElement( 'html' );
el.innerHTML = "<html><head><title>titleTest</title></head><body><...