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How to check if a file is a valid image file?
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That won't be sufficient if he's really testing for "valid" images; the presence of a magic number doesn't guarantee that the file hasn't been truncated, for example.
– Ben Blank
May 20 '09 at 18:11
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Get difference between 2 dates in JavaScript? [duplicate]
...day. As for always returning a positive number, that was a feature :) Typically when one talks about the number of days between two dates, that number is positive. If direction matters, just remove the Math.abs().
– TNi
Jul 11 '10 at 22:38
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Force R not to use exponential notation (e.g. e+10)?
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This is a bit of a grey area. You need to recall that R will always invoke a print method, and these print methods listen to some options. Including 'scipen' -- a penalty for scientific display. From help(options):
‘scipen’: integer. A penalty to be applied wh...
Can I use jQuery with Node.js?
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Note: The original answer fails to mention that it you will need to install jsdom as well using npm install jsdom
Update (late 2013): The official jQuery team finally took over the management of the jquery package on npm:
npm install jquery
Then:
require("jsdom").env("", function (err, wind...
How do I determine file encoding in OS X?
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That's a function call you would use if you want to write a program. From the command line, just type ls -l@ <filename> to see what attributes are set for the file. To see the actual attribute, type xattr -p com.apple.TextEncoding <fil...
jQuery OR Selector?
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It should be noted this isn't really an 'or' selector, more like multiple selectors in one.
– alex
Feb 15 '10 at 3:57
50
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Better way to sum a property value in an array
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Updated Answer
Due to all the downsides of adding a function to the Array prototype, I am updating this answer to provide an alternative that keeps the syntax similar to the syntax originally requested in the question.
class TravellerCollection e...
Throw an error in a MySQL trigger
...e SIGNAL syntax to throw an exception:
signal sqlstate '45000' set message_text = 'My Error Message';
State 45000 is a generic state representing "unhandled user-defined exception".
Here is a more complete example of the approach:
delimiter //
use test//
create table trigger_test
(
id int...
Eclipse - no Java (JRE) / (JDK) … no virtual machine
... (the first one referenced by your PATH)
Three things to remember:
"Installing" a JRE or a JDK can be as simple as unzipping or copying it from another computer: there is no special installation steps, and you can have as many different JVM versions (1.4, 5.0, 6.0...) as you want, "installed" (co...
How to convert image to byte array
...ollows:
public static byte[] converterDemo(Image x)
{
ImageConverter _imageConverter = new ImageConverter();
byte[] xByte = (byte[])_imageConverter.ConvertTo(x, typeof(byte[]));
return xByte;
}
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