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How to get a substring of text?
I have text with length ~700. How do I get only ~30 of its first characters?
5 Answers
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In Python, what is the difference between “.append()” and “+= []”?
...ase the only difference is performance: append is twice as fast.
Python 3.0 (r30:67507, Dec 3 2008, 20:14:27) [MSC v.1500 32 bit (Intel)] on win32
Type "help", "copyright", "credits" or "license" for more information.
>>> import timeit
>>> timeit.Timer('s.append("something")', 's...
JSON left out Infinity and NaN; JSON status in ECMAScript?
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edited Sep 18 '09 at 3:40
answered Sep 14 '09 at 21:34
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How to format numbers as currency string?
...ofits.toFixed(2) //returns 2489.82
profits.toFixed(7) //returns 2489.8237000 (pads the decimals)
All you need is to add the currency symbol (e.g. "$" + profits.toFixed(2)) and you will have your amount in dollars.
Custom function
If you require the use of , between each digit, you can use this...
C# equivalent to Java's charAt()?
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201
You can index into a string in C# like an array, and you get the character at that index.
Exam...
Printing tuple with string formatting in Python
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205
>>> thetuple = (1, 2, 3)
>>> print "this is a tuple: %s" % (thetuple,)
this i...
How to iterate object in JavaScript? [duplicate]
... Neuron
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answered Mar 19 '13 at 10:14
kavinkavin
1,70411 gold badge10...
How can I catch a ctrl-c event?
...r;
sigemptyset(&sigIntHandler.sa_mask);
sigIntHandler.sa_flags = 0;
sigaction(SIGINT, &sigIntHandler, NULL);
pause();
return 0;
}
share
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improve this answer
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How to express infinity in Ruby?
...y 1.8.6, 1.8.7, and 1.9.2 you have Float.infinite?.
PositiveInfinity = +1.0/0.0
=> Infinity
NegativeInfinity = -1.0/0.0
=> -Infinity
CompleteInfinity = NegativeInfinity..PositiveInfinity
=> -Infinity..Infinity
*I've verified this in Ruby 1.8.6 and 1.9.2
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Converting between datetime, Timestamp and datetime64
... np
>>> dt = datetime.utcnow()
>>> dt
datetime.datetime(2012, 12, 4, 19, 51, 25, 362455)
>>> dt64 = np.datetime64(dt)
>>> ts = (dt64 - np.datetime64('1970-01-01T00:00:00Z')) / np.timedelta64(1, 's')
>>> ts
1354650685.3624549
>>> datetime.utcfromt...