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Remove empty elements from an array in Javascript
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1151
EDIT: This question was answered almost nine years ago when there were not many useful built-in...
How to change href of tag on button click through javascript
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Nick Craver♦Nick Craver
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Rename a dictionary key
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765
For a regular dict, you can use:
mydict[new_key] = mydict.pop(old_key)
For an OrderedDict, I ...
C++ Structure Initialization
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WyzardWyzard
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8
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How to round up to the nearest 10 (or 100 or X)?
...nice base values from 1 to 10. The default is set to the even numbers plus 5.
roundUpNice <- function(x, nice=c(1,2,4,5,6,8,10)) {
if(length(x) != 1) stop("'x' must be of length 1")
10^floor(log10(x)) * nice[[which(x <= 10^floor(log10(x)) * nice)[[1]]]]
}
The above doesn't work when...
Python `if x is not None` or `if not x is None`?
...nce, as they compile to the same bytecode:
Python 2.6.2 (r262:71600, Apr 15 2009, 07:20:39)
>>> import dis
>>> def f(x):
... return x is not None
...
>>> dis.dis(f)
2 0 LOAD_FAST 0 (x)
3 LOAD_CONST 0 (None)
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What is a lambda expression in C++11?
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1535
The problem
C++ includes useful generic functions like std::for_each and std::transform, whic...
Finding median of list in Python
...y taking the average of the two middle values:
>>> median([1, 3, 5])
3
>>> median([1, 3, 5, 7])
4.0
Usage:
import statistics
items = [6, 1, 8, 2, 3]
statistics.median(items)
#>>> 3
It's pretty careful with types, too:
statistics.median(map(float, items))
#>>...
How to upgrade PowerShell version from 2.0 to 3.0
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58
Download and install from http://www.microsoft.com/en-us/download/details.aspx?id=34595. You ne...
Cannot create an NSPersistentStoreCoordinator with a nil model
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157
I had exactly the same error message as the original post. I was wrestling with this for hours....