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How to pull a random record using Django's ORM?
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Using order_by('?') will kill the db server on the second day in production. A better way is something like what is described in Getting a random row from a relational database.
from django.db.models.aggregates import Count
from random...
How to set radio button checked as default in radiogroup?
....getId() works as well, thx Ramesh
EDIT2:
android:checkedButton="@+id/my_radiobtn"
works in radiogroup xml
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What is Weak Head Normal Form?
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A good explanation with examples is given at http://foldoc.org/Weak+Head+Normal+Form Head normal form simplifies even the bits of an expression inside of a function abstraction, while "weak" head normal form stops at function abstractions.
From the source, if you have...
Alphabet range in Python
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>>> import string
>>> string.ascii_lowercase
'abcdefghijklmnopqrstuvwxyz'
If you really need a list:
>>> list(string.ascii_lowercase)
['a', 'b', 'c', 'd', 'e', 'f', 'g', 'h', 'i', 'j', 'k', 'l', 'm', 'n', 'o', 'p', 'q', 'r', 's', 't', 'u', 'v', 'w...
Force R not to use exponential notation (e.g. e+10)?
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How to get the name of the calling method?
...eem to work in Rails 5.2.1. In Rails controller this returns "block in make_lambda". I guess this is for Ruby only.
– dcangulo
Nov 14 '18 at 4:59
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How to deal with cyclic dependencies in Node.js
...orts forward declaration:
module.exports = {
};
// Controllers:
var other_module = require('./other_module');
// Functions:
var foo = function () {
};
// Module exports injects:
module.exports.foo = foo;
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Pass Additional ViewData to a Strongly-Typed Partial View
...e child control which will be reset otherwise
– Simon_Weaver
Jul 6 '13 at 10:44
12
This is defini...
What is the JavaScript convention for no operation?
...noop = ()=>{};
const noopProto = Function.prototype;
function test (_noop, iterations) {
const before = performance.now();
for(let i = 0; i < iterations; i++) _noop();
const after = performance.now();
const elapsed = after - before;
console.info(`${elapsed.toFixed(...
HTML5 Canvas 100% Width Height of Viewport?
...izes the canvas to the window.innerHeight and window.innerWidth.
Example: http://jsfiddle.net/jaredwilli/qFuDr/
HTML
<canvas id="canvas"></canvas>
JavaScript
(function() {
var canvas = document.getElementById('canvas'),
context = canvas.getContext('2d');
// res...