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Can I make the foreign key field optional in Django model
... answered Jul 8 '11 at 4:58
Abid AAbid A
5,99833 gold badges2828 silver badges3030 bronze badges
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setup cron tab to specific time of during weekdays
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Same as you did for hours:
*/2 09-18 * * 1-5 /path_to_script
0 and 7 stand for Sunday
6 stands for Saturday
so, 1-5 means from Monday to Friday
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ReferenceError: event is not defined error in Firefox
...eventDefault();
var categories = $(this).attr('rel');
$('.pages').hide();
$(categories).fadeIn();
});
You need "event" to be a parameter to the handlers. WebKit follows IE's old behavior of using a global symbol for "event", but Firefox doesn't. When you're using jQuery, that librar...
Why should I learn Lisp? [closed]
...an appropriate response would be. I also wrote a routine to solve a 3x3 slide puzzle (an algorithm which could easily be extended to larger slide puzzles).
In summary, learning Lisp (or Scheme) may not yield many practical applications beyond AI but it is an extremely valuable learning experience,...
Python's “in” set operator
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well I suppose a list or even a string can be considered to have similar properties to a set. They are a collection of elements.
– Arnab Ghosal
Jan 3 '12 at 7:08
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ggplot: How to increase spacing between faceted plots?
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Use the theme function:
library(grid)
p + theme(panel.spacing = unit(2, "lines"))
See also here: Slicing plots generated by ggplot2
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Difference between `set`, `setq`, and `setf` in Common Lisp?
...written as
(setf (car x) 42)
For symmetry and generality, SETF also provided the functionality of SETQ. At this point it would have been correct to say that SETQ was a Low-level primitive, and SETF a high-level operation.
Then symbol macros happened. So that symbol macros could work transparentl...
How to express infinity in Ruby?
...bing the properties of Infinity in Ruby (including Infinity derived via dividing by 0): nithinbekal.com/posts/ruby-infinity - should give you an idea whether or not it's safe. (For what it's worth, IMHO messing around with numeric Infinity values is virtually never safe or truly needed regardless of...
Assign variables to child template in {% include %} tag Django
... var channelOptions = {
tags: "".split(" "),
id: "1"
};
initTagRenderer("".split(" "), "".split(" "), channelOptions);
StackExchange.using("externalEditor", function() {
// Have to fire editor after snippets, if snippets enabled...
How do I convert datetime to ISO 8601 in PHP
...t the colon, not a mixture) - date('c') does produces a strict ISO 8601 valid date - This could cause hard to trace bugs if code expects a strict ISO 8601 datetime format. Ref: en.wikipedia.org/wiki/ISO_8601
– ckm
Mar 23 '15 at 1:42
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