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Fastest way to determine if an integer is between two integers (inclusive) with known sets of values
...s an old trick to do this with only one comparison/branch. Whether it'll really improve speed may be open to question, and even if it does, it's probably too little to notice or care about, but when you're only starting with two comparisons, the chances of a huge improvement are pretty remote. The c...
Primary key or Unique index?
...ork we have a big database with unique indexes instead of primary keys and all works fine.
15 Answers
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Doctrine and composite unique keys
...html
So the original example could look something like this:
/**
* @var string $videoDimension
*
* @ORM\Id @ORM\Column(type="string")
*/
private $videoDimension;
/**
* @var string $videoBitrate
*
* @ORM\Id @ORM\Column(type="string")
*/
private $videoBitrate;
A few notes here:
Column "...
pandas read_csv and filter columns with usecols
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If your csv file contains extra data, columns can be deleted from the DataFrame after import.
import pandas as pd
from StringIO import StringIO
csv = r"""dummy,date,loc,x
bar,20090101,a,1
bar,20090102,a,3
bar,20090103,a,5
bar,20090101,b,1
bar,200...
How can I fix the Microsoft Visual Studio error: “package did not load correctly”?
I installed Visual Studio 2012 and DevExpress 13.1. As Visual Studio started, it generated an error shown by this attached image,
...
Wait for page load in Selenium
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does this really work all the time? Maybe Im missing something from your code but you are waiting for the dom to be in ready state. But consider that if your code executes too fast the previous page might not be unloaded yet and it will ...
How to list variables declared in script in bash?
... I have to make something to save them to file.
My question is how to list all variables declared in my script and get list like this:
...
Having Django serve downloadable files
...ntended since apache module X-Sendfile cannot decode the smart_str encoded string. Thus for example "Örinää.mp3" file cannot be served. And if one omits the smart_str, the Django itself throws ascii encoding error because all headers are encoded to ascii format before sending. Only way that I kno...
Why use apparently meaningless do-while and if-else statements in macros?
...into
if (corge)
f(corge); g(corge);
else
gralt();
which is syntactically incorrect, as the else is no longer associated with the if. It doesn't help to wrap things in curly braces within the macro, because a semicolon after the braces is syntactically incorrect.
if (corge)
{f(corge); g(co...
Using node.js as a simple web server
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Simplest Node.js server is just:
$ npm install http-server -g
Now you can run a server via the following commands:
$ cd MyApp
$ http-server
If you're using NPM 5.2.0 or newer, you can use http-server without installing it with npx. This isn't recommended for u...