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What's the difference between lapply and do.call?

I'm learning R recently and confused by two function: lapply and do.call . It seems that they're just similar to map function in Lisp. But why are there two functions with such a different name? Why doesn't R just use a function called map ? ...
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What is the equivalent of “none” in django templates?

... None, False and True all are available within template tags and filters. None, False, the empty string ('', "", """""") and empty lists/tuples all evaluate to False when evaluated by if, so you can easily do {% if profile.user.first_name == None...
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How do I find the most recent git commit that modified a file?

...ts looking at the history of specific files (and directories), so you can call it like this: git log my/file.c If you really only want to list the one most recent commit, for example to use it in a script, use the -n 1 option: git log -n 1 --pretty=format:%H -- my/file.c --pretty=format:%h tel...
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Preventing Laravel adding multiple records to a pivot table

...ems()->where('foreign_key', $foreignKey)->count() Which, well, actually performs an additional query too '^^ But I don't need to fetch and hydrate the whole collection unless I really need it. – Silence May 24 '15 at 13:57 ...
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How to align checkboxes and their labels consistently cross-browsers

...lems that plagues me constantly. How do folks around Stack Overflow vertically align checkboxes and their labels consistently cross-browser ? Whenever I align them correctly in Safari (usually using vertical-align: baseline on the input ), they're completely off in Firefox and IE. Fix it ...
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HTML5 Number Input - Always show 2 decimal places

... You can't really, but you a halfway step might be: <input type='number' step='0.01' value='0.00' placeholder='0.00' /> share | ...
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Script parameters in Bash

...at can make it easier to parse named arguments on the command line, but usually for simple shell scripts you should just use the easy way, if it's no problem. Then you can do: /usr/local/bin/abbyyocr9 -rl Swedish -if "$1" -of "$2" 2>&1 The double quotes around the $1 and the $2 are not al...
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Change old commit message on Git

...situation, a git rebase -i --abort might be needed to reset everything and allow you to try again) As Dave Vogt mentions in the comments, git rebase --continue is for going to the next task in the rebasing process, after you've amended the first commit. Also, Gregg Lind mentions in his answer the r...
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RegEx: Grabbing values between quotation marks

...gt;>> string = '"Foo Bar" "Another Value"' >>> print re.findall(r'"(.*?)"', string) ['Foo Bar', 'Another Value'] share | improve this answer | follow ...
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How to check if a variable is an integer in JavaScript?

... @connorbode in javascript all numbers have the same type (there is no float or double), so 2.0 === 2 since the unnecessary decimal is just a different representation of the same number, thus parseInt(2.0) === 2.0 is equivalent to parseInt(2) === 2 whi...