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Can dplyr package be used for conditional mutating?
...and the conditions (except for the default value of NA at the end) are mutually exclusive, as is the case in the question, then we can use an arithmetic expression such that each term is multiplied by the desired result using na_if at the end to replace 0 with NA.
df %>%
mutate(g = 2 * (a == 2 ...
How to make vim paste from (and copy to) system's clipboard?
...ent working file. It so happens I have to either open gedit or type it manually.
31 Answers
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Cached, PHP generated Thumbnails load slowly
...as how to make this site, load faster. First we needed to read these waterfalls. Thanks all for your suggestions on the waterfall readout analysis. Evident from the various waterfall graphs shown here is the main bottleneck: the PHP-generated thumbnails. The protocol-less jquery loading from CDN adv...
jQuery .val change doesn't change input value
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This is totally correct, by using setAttribute or jQuery's attr you will also affect the DOM element's value: jsfiddle.net/a8SxF/1
– TheZ
Aug 8 '12 at 21:58
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How to start a Process as administrator mode in C# [duplicate]
...ve a Visual Studio Windows app project. I've added code to download an installer update file. The installer after it has finished downloading would need administrator privileges to run. I have added a manifest file.
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Print in one line dynamically
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From http://docs.python.org/reference/simple_stmts.html#print: > A '\n' character is written at the end, unless the print statement ends with a comma. This is the only action if the statement contains just the keyword print.
– ewall
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Regex for password must contain at least eight characters, at least one number and both lower and up
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"^(?=.*[A-Za-z])(?=.*\d)[A-Za-z\d]{8,}$" does not allow symbols as one of the 8 characters
– Wee
Jan 6 '15 at 2:30
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Android Bitmap to Base64 String
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The problem with jeet's answer is that you load all bytes of the image into a byte array, which will likely crash the app in low-end devices. Instead, I would first write the image to a file and read it using Apache's Base64InputStream class. Then you can create the Base64...
Cleaner way to do a null check in C#? [duplicate]
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Is this really considered cleaner?
– ClassicThunder
Jul 16 '13 at 13:35
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Using helpers in model: how do I include helper dependencies?
...cerns with active record models. That's a terrible practice. A much better approach is to put a standalone input data sanitizer object in front of AR and retrieve "clean" attributes from it.
– solnic
Jul 29 '14 at 10:52
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