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Convert System.Drawing.Color to RGB and Hex Value
... and need your kind advice. In addition, I dont know whether there is any existing method to do the same.
6 Answers
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What is the difference between __init__ and __call__?
...sed to do that:
class Foo:
def __init__(self, a, b, c):
# ...
x = Foo(1, 2, 3) # __init__
The second implements function call operator.
class Foo:
def __call__(self, a, b, c):
# ...
x = Foo()
x(1, 2, 3) # __call__
...
Linear Regression and group by in R
... year=rep(1:10, 2),
response=c(rnorm(10), rnorm(10)))
xyplot(response ~ year, groups=state, data=d, type='l')
fits <- lmList(response ~ year | state, data=d)
fits
#------------
Call: lmList(formula = response ~ year | state, data = d)
Coefficients:
(Intercept) ye...
Are list-comprehensions and functional functions faster than “for loops”?
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The following are rough guidelines and educated guesses based on experience. You should timeit or profile your concrete use case to get hard numbers, and those numbers may occasionally disagree with the below.
A list comprehension is usually a tiny bit faster than the precisely equivalent ...
How to identify numpy types in python?
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Old question but I came up with a definitive answer with an example. Can't hurt to keep questions fresh as I had this same problem and didn't find a clear answer. The key is to make sure you have numpy imported, and then run the isinstance bool. While this may seem simple, if you are ...
Why does Windows64 use a different calling convention from all other OSes on x86-64?
...D has an ABI specification that describes the calling convention to use on x86-64. All OSes follow it, except for Windows which has it's own x86-64 calling convention. Why?
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Does Python have “private” variables in classes?
... emulate private variables for some reason, you can always use the __ prefix from PEP 8. Python mangles the names of variables like __foo so that they're not easily visible to code outside the class that contains them (although you can get around it if you're determined enough, just like you can get...
How to sum a variable by group
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Using aggregate:
aggregate(x$Frequency, by=list(Category=x$Category), FUN=sum)
Category x
1 First 30
2 Second 5
3 Third 34
In the example above, multiple dimensions can be specified in the list. Multiple aggregated metrics of the same d...
Find the division remainder of a number
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you are looking for the modulo operator:
a % b
for example:
26 % 7
Of course, maybe they wanted you to implement it yourself, which wouldn't be too difficult either.
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C dynamically growing array
...aw" list of in-game entities, and I intend to make an array holding an index number (int) of an indeterminate number of entities, for processing various things. I would like to avoid using too much memory or CPU for keeping such indexes...
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