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Generate random numbers with a given (numerical) distribution
...bers in O(k log n). Since normal Python lists are inefficient, you can use array module.
If you insist on constant space, you can do the following; O(n) time, O(1) space.
def random_distr(l):
r = random.uniform(0, 1)
s = 0
for item, prob in l:
s += prob
if s >= r:
...
Shortcuts in Objective-C to concatenate NSStrings
...ethod, removing some of the need for extra temp strings.
Second, use an NSArray to concatenate via the componentsJoinedByString method.
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How do I test for an empty JavaScript object?
...bj.constructor === Object
Note, though, that this creates an unnecessary array (the return value of keys).
Pre-ECMA 5:
function isEmpty(obj) {
for(var prop in obj) {
if(obj.hasOwnProperty(prop)) {
return false;
}
}
return JSON.stringify(obj) === JSON.stringify({});
}
jQuer...
jQuery set checkbox checked
...hen appending to an element directly in the page). I am looping through an array of data ("queriesToAddToGroup") to see if any rows have an attribute of COPY. If so I want to turn on the checkbox within the window that sets that attribute when a user saves from this window.
...
T-SQL stored procedure that accepts multiple Id values
...aintained the authoritative answer to this question for the last 16 years: Arrays and Lists in SQL Server.
There are at least a dozen ways to pass an array or list to a query; each has their own unique pros and cons.
Table-Valued Parameters. SQL Server 2008 and higher only, and probably the clos...
Mark parameters as NOT nullable in C#/.NET?
...else to assign to it? What other value could we pave a freshly
allocated array of references over with, until you get around to
filling it in?
Also, sometimes null is a sensible value in and of itself. Sometimes
you want to represent the fact that, say, a field doesn’t have a
value. T...
Find out how much memory is being used by an object in Python [duplicate]
...Using the bregman.suite, some tests with sys.getsizeof output a copy of an array object (data) in an object instance as being bigger than the object itself (mfcc).
>>> mfcc = MelFrequencyCepstrum(filepath, params)
>>> data = mfcc.X[:]
>>> sys.getsizeof(mfcc)
64
>>&g...
How to get instance variables in Python?
Is there a built-in method in Python to get an array of all a class' instance variables? For example, if I have this code:
...
Call apply-like function on each row of dataframe with multiple arguments from each row
...he delta, power, sig.level params by name instead of sticking them into an array with pre-specified positions and then referencing those position, for the reason of being more robust. in any case thanks so much!
– vasek1
Feb 25 '13 at 2:37
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How to extract URL parameters from a URL with Ruby or Rails?
...he full URL like the op asks, and the result values are strings instead of arrays, like in the other answers. thanks.
– jackocnr
Nov 15 '13 at 23:25
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