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How do you match only valid roman numerals with a regular expression?
...L|L?X{0,3})(IX|IV|V?I{0,3})$
Breaking it down, M{0,4} specifies the thousands section and basically restrains it to between 0 and 4000. It's a relatively simple:
0: <empty> matched by M{0}
1000: M matched by M{1}
2000: MM matched by M{2}
3000: MMM matched by M{3}
4000:...
Regular expression to match DNS hostname or IP Address?
Does anyone have a regular expression handy that will match any legal DNS hostname or IP address?
21 Answers
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Understanding the Use of ColorMatrix and ColorMatrixColorFilter to Modify a Drawable's Hue
I'm working on a UI for an app, and I'm attempting to use grayscale icons, and allow the user to change the theme to a color of their choosing. To do this, I'm trying to just apply a ColorFilter of some sort to overlay a color on top of the drawable. I've tried using PorterDuff.Mode.MULTIPLY, and it...
Why doesn't Python have a sign function?
I can't understand why Python doesn't have a sign function. It has an abs builtin (which I consider sign 's sister), but no sign .
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How to detect a Christmas Tree? [closed]
...
I have an approach which I think is interesting and a bit different from the rest. The main difference in my approach, compared to some of the others, is in how the image segmentation step is performed--I used the DBSCAN clustering algorithm from Python's scikit-learn; it...
How to change the output color of echo in Linux
I am trying to print a text in the terminal using echo command.
30 Answers
30
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Any reason not to use '+' to concatenate two strings?
...e Python interpreter has to create a new string object for each iteration, and it ends up taking quadratic time. (Recent versions of CPython can apparently optimize this in some cases, but other implementations can't, so programmers are discouraged from relying on this.) ''.join is the right way t...
postgresql return 0 if returned value is null
...price DESC ) FROM web_price_scan
WHERE listing_Type = 'AARM'
AND u_kbalikepartnumbers_id = 1000307
AND ( EXTRACT( DAY FROM ( NOW() - dateEnded ) ) ) * 24 < 48
AND COALESCE( price, 0 ) > ( SELECT AVG( COALESCE( price, 0 ) )* 0.50
...
How can I get the current network interface throughput statistics on Linux/UNIX? [closed]
Tools such as MRTG provide network throughput / bandwidth graphs for the current network utilisation on specific interfaces, such as eth0. How can I return that information at the command line on Linux/UNIX?
...
Outline effect to text
...eady supported text-shadow property (supported in Chrome, Firefox, Opera, and IE 9 I believe).
Use four shadows to simulate a stroked text:
.strokeme {
color: white;
text-shadow: -1px -1px 0 #000, 1px -1px 0 #000, -1px 1px 0 #000, 1px 1px 0 #000;
}
<div class="strokeme">
Thi...