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Android splash screen image sizes to fit all devices
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what size to put in every drawable folder ( ldpi , mdpi , hdpi , and xhdpi ). My application is supposed to run good and beautiful on all phones and tablets. What sizes (in pixels) should I create so the splash displays nice on all screens?
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What does “dereferencing” a pointer mean?
Please include an example with the explanation.
6 Answers
6
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Is there a better way to iterate over two lists, getting one element from each list for each iterati
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In Python 2.x you might consider itertools.izip instead (zip does the same thing in Python 3.x).
– Nicholas Riley
Dec 17 '09 at 2:08
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Null vs. False vs. 0 in PHP
...The var has not been initialized.
False means "not true in a boolean context". Used to explicitly show you are dealing with logical issues.
0 is an int. Nothing to do with the rest above, used for mathematics.
Now, what is tricky, it's that in dynamic languages like PHP, all of them have a value ...
Grouping functions (tapply, by, aggregate) and the *apply family
...rs) that much of the functionality of the *apply family is covered by the extremely popular plyr package, the base functions remain useful and worth knowing.
This answer is intended to act as a sort of signpost for new useRs to help direct them to the correct *apply function for their particular pr...
Element-wise addition of 2 lists?
... list2) )
[5, 7, 9]
or zip with a list comprehension:
>>> [sum(x) for x in zip(list1, list2)]
[5, 7, 9]
Timing comparisons:
>>> list2 = [4, 5, 6]*10**5
>>> list1 = [1, 2, 3]*10**5
>>> %timeit from operator import add;map(add, list1, list2)
10 loops, best of ...
Check if a number is int or float
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Use isinstance.
>>> x = 12
>>> isinstance(x, int)
True
>>> y = 12.0
>>> isinstance(y, float)
True
So:
>>> if isinstance(x, int):
print 'x is a int!'
x is a int!
_EDIT:_
As pointed out, in case o...
Haskell composition (.) vs F#'s pipe forward operator (|>)
...eralizing let-bindings are sufficiently different as to affect this. For example, I know in F# sometimes writing
let f = exp
will not compile, and you need explicit eta-conversion:
let f x = (exp) x // or x |> exp
to make it compile. This also steers people away from points-free/compos...
How do I list all files of a directory?
...rt walk
f = []
for (dirpath, dirnames, filenames) in walk(mypath):
f.extend(filenames)
break
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Why don't Java's +=, -=, *=, /= compound assignment operators require casting?
Until today, I thought that for example:
11 Answers
11
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