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Rails: How do I create a default value for attributes in Rails activerecord's model? [duplicate]
...lues
def default_values
self.status ||= 'P' # note self.status = 'P' if self.status.nil? might be safer (per @frontendbeauty)
end
end
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How to list only top level directories in Python?
...to get the real path):
>>> [ name for name in os.listdir(thedir) if os.path.isdir(os.path.join(thedir, name)) ]
['ctypes', 'distutils', 'encodings', 'lib-tk', 'config', 'idlelib', 'xml', 'bsddb', 'hotshot', 'logging', 'doc', 'test', 'compiler', 'curses', 'site-packages', 'email', 'sqlite3'...
Checking to see if one array's elements are in another array in PHP
...antwparks then why in PHP docs about this function they say "Returns FALSE if var exists and has a non-empty, non-zero value. Otherwise returns TRUE. The following things are considered to be empty: array() (an empty array)"? Source: php.net/manual/en/function.empty.php
– Pere
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Most pythonic way to delete a file which may not exist
I want to delete the file filename if it exists. Is it proper to say
13 Answers
13
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Finding differences between elements of a list
Given a list of numbers, how does one find differences between every ( i )-th elements and its ( i+1 )-th?
10 Answers
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JavaScript displaying a float to 2 decimal places
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float_num.toFixed(2);
Note:toFixed() will round or pad with zeros if necessary to meet the specified length.
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Is there an R function for finding the index of an element in a vector?
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%in% returns a logical vector as long as the first argument, with a TRUE if that value can be found in the second argument and a FALSE otherwise.
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Python Write bytes to file
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If you want to write bytes then you should open the file in binary mode.
f = open('/tmp/output', 'wb')
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Custom error pages on asp.net MVC3
... handle custom errors. I define an ErrorsController with actions handling different HTTP errors:
public class ErrorsController : Controller
{
public ActionResult General(Exception exception)
{
return Content("General failure", "text/plain");
}
public ActionResult Http404()
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Equivalent of String.format in jQuery
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Warning: This will format recursively: so if you have {0}{1}, {0} will be replaced first, and then all occurrences of {1} in both the already-substituted text and the original format will be replaced.
– Zenexer
Jul 1 '13 at 18:1...