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How to pull a random record using Django's ORM?
...e_or_none = Model.objects.raw('''
select * from {0} limit 1
offset floor(random() * (select count(*) from {0}))
'''.format(Model._meta.db_table)).first()
Be aware that this will raise an index error if the table is empty. Write yourself a model-agnostic helper function to check for that.
...
HTML5 Video Dimensions
...Id("id_video");
var width = v.offsetWidth;
v.height = Math.floor(width*(9/16)); // dynamically setting video height to maintain aspect ratio
},
});
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Looping in a spiral
...// a the position on the current square
// n = p + a
var r = Math.floor((Math.sqrt(n + 1) - 1) / 2) + 1;
// compute radius : inverse arithmetic sum of 8+16+24+...=
var p = (8 * r * (r - 1)) / 2;
// compute total point on radius -1 : arithmetic sum of 8+16+24+...
var en = r...
jQuery AJAX cross domain
...ticles finally figured it out. Here is my summary.
server script (.php, .jsp, ...) must return http response header Access-Control-Allow-Origin: *
before using jQuery ajax set this flag in javascript: jQuery.support.cors = true;
you may set flag once or everytime before using jQuery ajax function...
Attach to a processes output for viewing
... container1 ubuntu bash -c -i "COUNT=0; while true; do echo Keep the dance floor beat going; ((COUNT++)); sleep 1; echo \"Count is: \${COUNT}\"; done;" ``` In another terminal: ``` docker exec -it container1 tail -f /proc/1/fd/1 ```
– JacobWuzHere
Dec 27 '16 ...
How to open existing project in Eclipse
...tion under Import->General.
See:
http://help.eclipse.org/helios/index.jsp?topic=%2Forg.eclipse.platform.doc.user%2Ftasks%2Ftasks-importproject.htm
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Use Fieldset Legend with bootstrap
I'm using Bootstrap for my JSP page.
5 Answers
5
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Are the shift operators () arithmetic or logical in C?
...he effect of mathematically dividing it by 2n and rounding towards −∞ (floor); thus right shifting is different for non-negative and negative values.
for X ≥ 0, X >> n = X / 2n = trunc(X ÷ 2n)
for X < 0, X >> n = floor(X ÷ 2n)
where ÷ is mathematical division, / is integer ...
Getting Spring Application Context
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A good example is JSP tags; their creation is goverened by the servlet container, so they have no choice but to obtain the context statically. Spring provides base Tag classes, and they use BeanFactoryLocators to get the contexts they need.
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Is there a Java API that can create rich Word documents? [closed]
...well as corresponding PDF documents, from a Java Web application (a Struts/JSP framework).
OpenOffice UNO also lets you build MS-Office-compatible charts, spreadsheets, presentations, etc. We were able to dynamically build sophisticated Word documents, including charts and tables.
We simplifi...