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Fastest way to replace NAs in a large data.table

....805 12.301 134.985 system.time(a_andrie = f_andrie(dt1)) Error: cannot allocate vector of size 305.2 Mb Timing stopped at: 14.541 7.764 68.285 system.time(f_dowle(dt1)) user system elapsed 7.452 4.144 19.590 # EDIT has faster than this identical(a_gdata, dt1) [1] TRUE Note th...
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What is the difference between ${var}, “$var”, and “${var}” in the Bash shell?

...bar', so loop runs once and done # prints nothing (actually "") var="foo bar" for i in "${var}bar"; do # Expands to 'for i in "foo barbar"; do...' echo $i # so runs the loop once done # foo barbar Note that "${var}bar" in the second example above could also ...
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JavaScript to scroll long page to DIV

...ding to the great compatibility-tables on quirksmode, this is supported by all major browsers! share | improve this answer | follow | ...
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Quickest way to compare two generic lists for differences

...2.Except(list1).ToList(); I suspect there are approaches which would actually be marginally faster than this, but even this will be vastly faster than your O(N * M) approach. If you want to combine these, you could create a method with the above and then a return statement: return !firstNotSecon...
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How does the getView() method work when creating your own custom adapter?

...ided so you can inflate your view into that for proper layout parameters. All these together can be used to effectively create the view that will appear in your list (or other view that takes an adapter): public View getView(int position, @Nullable View convertView, ViewGroup parent){ if (conv...
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How do I merge my local uncommitted changes into another Git branch?

... Stashing, temporary commits and rebasing may all be overkill. If you haven't added the changed files to the index, yet, then you may be able to just checkout the other branch. git checkout branch2 This will work so long as no files that you are editing are different ...
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What is the difference between user variables and system variables?

...eating the environment for an application. System variables are shared for all users, but user variables are only for your account/profile. If you deleted the system ones by accident, bring up the Registry Editor, then go to HKLM\ControlSet002\Control\Session Manager\Environment (assuming your curr...
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How to Apply global font to whole HTML document

... want to make it have the same font-family and the same text-size ignoring all inner formatting of text. 6 Answers ...
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CSS force image resize and keep aspect ratio

...ht:95px; width: auto; height: auto; } <p>This image is originally 400x400 pixels, but should get resized by the CSS:</p> <img width="400" height="400" src="http://i.stack.imgur.com/aEEkn.png"> This will make image shrink if it's too big for specified area (as downsi...
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What are the implications of using “!important” in CSS? [duplicate]

...e more specific a selector is, the more importance is added to it. This usually coincides with how often the selected element occurs. For example: button { color: black; } button.highlight { color: blue; font-size: 1.5em; } button#buyNow { color: green; font-size: 2em; } ...