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Installing older version of R package

... To install an older version of a package from source (within R): packageurl <- "http://cran.r-project.org/src/contrib/Archive/ggplot2/ggplot2_0.9.1.tar.gz" install.packages(packageurl, repos=NULL, type="source") If this doesn'...
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Django-Admin: CharField as TextArea

... Starting from Django 1.7 you need to add also fields = '__all__' under class Meta:. – skoll May 4 '16 at 11:43 2 ...
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Drawing a connecting line between two elements [closed]

...ilding applications and integrations for popular libraries, and is commercially licensed. share | improve this answer | follow | ...
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CodeIgniter: Create new helper?

...o it. <?php if ( ! defined('BASEPATH')) exit('No direct script access allowed'); if ( ! function_exists('test_method')) { function test_method($var = '') { return $var; } } Save this to application/helpers/ . We shall call it "new_helper.php" The first line exists to ...
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Select unique or distinct values from a list in UNIX shell script

...n the following input: class jar jar jar bin bin java uniq will output all lines exactly once: class jar bin java uniq -d will output all lines that appear more than once, and it will print them once: jar bin uniq -u will output all lines that appear exactly once, and it will print them ...
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What's the difference between “static” and “static inline” function?

... to think that static should be used in translation units and benefit from extra check compiler does to find unused functions. And static inline should be used in header files to provide functions that can be in-lined (due to absence of external linkage) without issuing warnings. Unfortunately I ca...
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UIBarButtonItem with custom image and no border

...ation code here } @end So anywhere in your code you can create bar item calling this method (provided that you include a header with its declaration). P.S. You do not need to use 'v' UIView as you can create UIBarButtonItem with a button as custom view directly. P.P.S. You also need [forward rel...
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Why is iterating through a large Django QuerySet consuming massive amounts of memory?

...rst time you iterate over it. For example, this will print the headline of all entries in the database: for e in Entry.objects.all(): print e.headline So your ten million rows are retrieved, all at once, when you first enter that loop and get the iterating form of the queryset. The wait ...
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Try-catch speeding up my code?

... I’ve always wondered why the C# compiler generates so many extraneous locals. For example, new array initialisation expressions always generate a local, but is never necessary to generate a local. If it allows the JITter to produce measurably more performant code, perhaps the C# comp...
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What's an easy way to read random line from a file in Unix command line?

... You can use shuf: shuf -n 1 $FILE There is also a utility called rl. In Debian it's in the randomize-lines package that does exactly what you want, though not available in all distros. On its home page it actually recommends the use of shuf instead (which didn't exist when it was cr...