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How do Python functions handle the types of the parameters that you pass in?
...object has a type, every object knows its type, it's impossible to accidentally or deliberately use an object of a type "as if" it was an object of a different type, and all elementary operations on the object are delegated to its type.
This has nothing to do with names. A name in Python doesn't "...
How does Bluebird's util.toFastProperties function make an object's properties “fast”?
... eval("o" + o); // ensure no dead code elimination
}
Sans one or two small optimizations - all the below is still valid.
Let's first discuss what it does and why that's faster and then why it works.
What it does
The V8 engine uses two object representations:
Dictionary mode - in which object ar...
How to make lists contain only distinct element in Python? [duplicate]
...ving
return list(_f(seq, idfun))
def _f(seq, idfun=None):
''' Originally proposed by Andrew Dalke '''
seen = set()
if idfun is None:
for x in seq:
if x not in seen:
seen.add(x)
yield x
else:
for x in seq:
x = idfun(x)
if x not in seen:
s...
Detect if a NumPy array contains at least one non-numeric value?
...the input could be a single float or numpy.float64 or even something oddball like a zero-dimensional array.
5 Answers
...
Plot correlation matrix into a graph
...the ballpark:
library(lattice)
#Build the horizontal and vertical axis information
hor <- c("214", "215", "216", "224", "211", "212", "213", "223", "226", "225")
ver <- paste("DM1-", hor, sep="")
#Build the fake correlation matrix
nrowcol <- length(ver)
cor <- matrix(runif(nrowcol*nro...
Natural Sort Order in C#
...
@linquize - He said .NET not Mono, so Linux/OSX isn't really a concern. Windows Phone/Metro didn't exist in 2008 when this answer was posted. And how often do you do file operations in Silverlight? So for the OP, and probably most other people, it was a suitable answer. In any cas...
Efficient way to apply multiple filters to pandas DataFrame or Series
...s to apply several filters to a Pandas DataFrame or Series object. Essentially, I want to efficiently chain a bunch of filtering (comparison operations) together that are specified at run-time by the user.
...
Access nested dictionary items via a list of keys?
...ist, value):
getFromDict(dataDict, mapList[:-1])[mapList[-1]] = value
All but the last element in mapList is needed to find the 'parent' dictionary to add the value to, then use the last element to set the value to the right key.
Demo:
>>> getFromDict(dataDict, ["a", "r"])
1
>>&g...
How do I add a path to PYTHONPATH in virtualenv
...
You can usually avoid having to do anything with PYTHONPATH by using .pth files. Just put a file with a .pth extension (any basename works) in your virtualenv's site-packages folder, e.g. lib\python2.7\site-packages, with the absolute p...
Is Big O(logn) log base e?
...nary search tree type of data structures, I see the Big O notation is typically noted as O(logn). With a lowercase 'l' in log, does this imply log base e (n) as described by the natural logarithm? Sorry for the simple question but I've always had trouble distinguishing between the different impli...