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Length of a JavaScript object
...an break enumerations in various libraries. Adding methods to Object is usually safe, though.
Here's an update as of 2016 and widespread deployment of ES5 and beyond. For IE9+ and all other modern ES5+ capable browsers, you can use Object.keys() so the above code just becomes:
var size = Object...
How to close current tab in a browser window?
...ndow.close();
or you can specify a different window.
So:
function close_window() {
if (confirm("Close Window?")) {
close();
}
}
with HTML:
<a href="javascript:close_window();">close</a>
or:
<a href="#" onclick="close_window();return false;">close</a>
You r...
How do I find the location of the executable in C? [duplicate]
...
To summarize:
On Unixes with /proc really straight and realiable way is to:
readlink("/proc/self/exe", buf, bufsize) (Linux)
readlink("/proc/curproc/file", buf, bufsize) (FreeBSD)
readlink("/proc/self/path/a.out", buf, bufsize) (Solaris)
On Unixes without /pr...
iOS 7 style Blur view
...bove, I recently reworked the blurs in GPUImage to support variable radii, allowing for the complete replication of the blur size in iOS 7's control center view. From that, I created the GPUImageiOS7BlurFilter class that encapsulates the proper blur size and color correction that Apple appears to be...
Linux: copy and create destination dir if it does not exist
...
oops, right. But then, test may be a bash builtin (especially if written as [[ -d "$d" ]]) and mkdir can not ;-)
– Michael Krelin - hacker
Oct 7 '09 at 17:00
1
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Port 80 is being used by SYSTEM (PID 4), what is that?
...P adress is 0.0.0.0, state = LISTENING: means that port 80 is listening to all interfaces (not used)
How to read NETSTAT -AN results:
https://sites.google.com/site/xiangyangsite/home/technical-tips/linux-unix/networks-related-commands-on-linux/how-to-read-netstat--an-results
...
How can the Euclidean distance be calculated with NumPy?
...
There's a function for that in SciPy. It's called Euclidean.
Example:
from scipy.spatial import distance
a = (1, 2, 3)
b = (4, 5, 6)
dst = distance.euclidean(a, b)
share
|
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Why can't I forward-declare a class in a namespace using double colons?
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All other answers were confusing to me but this "you can't declare a class within a namespace from outside that namespace. You have to be in the namespace." was very helpful hint to remember.
– dashesy
...
how to emulate “insert ignore” and “on duplicate key update” (sql merge) with postgresql?
...gsql-control-structures.html, example 40-2 right at the bottom.
That's usually the easiest way. You can do some magic with rules, but it's likely going to be a lot messier. I'd recommend the wrap-in-function approach over that any day.
This works for single row, or few row, values. If you're deali...
Rails I18n validation deprecation warning
... the following line inside the Rails::Application body
config.i18n.enforce_available_locales = true
The possible values are:
false: if you
want to skip the locale validation
don't care about locales
true: if you
want the application to raise an error if an invalid locale is passed (or)
wan...