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How to set -source 1.7 in Android Studio and Gradle
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This is essentially the same as the accepted answer.
– Kerem
Aug 12 '15 at 12:20
1
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In pure functional languages, is there an algorithm to get the inverse function?
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In some cases, yes! There's a beautiful paper called Bidirectionalization for Free! which discusses a few cases -- when your function is sufficiently polymorphic -- where it is possible, completely automatically to derive an inverse function. (It also discusses what makes...
Django: multiple models in one template using forms [closed]
...eparate project) OR creating a new Customer, then creating a Ticket and finally creating a Note assigned to the new ticket.
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How can I convert a series of images to a PDF from the command line on linux? [closed]
...rver I wrote in cgi/bash and want to be able to convert a bunch of images (all in one folder) to a pdf from the command line. How can that be done?
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Paste multiple columns together
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@baptiste ..possible without do.call?
– Anthony Damico
Jan 28 '13 at 23:11
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How to convert list of tuples to multiple lists?
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xs, ys = [x for x, y in zs], [y for x, y in zs]
return xs, ys
if __name__ == '__main__':
from timeit import timeit
setup_string='''\
N = 2000000
xs = list(range(1, N))
ys = list(range(N+1, N*2))
zs = list(zip(xs, ys))
from __main__ import t1, t2, t3
'''
print(f'zip:\t\t{timeit(...
UICollectionView current visible cell index
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The method [collectionView visibleCells] give you all visibleCells array you want. Use it when you want to get
- (void)scrollViewDidEndDecelerating:(UIScrollView *)scrollView{
for (UICollectionViewCell *cell in [self.mainImageCollection visibleCells]) {
NSIndexP...
Performance of Arrays vs. Lists
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Very easy to measure...
In a small number of tight-loop processing code where I know the length is fixed I use arrays for that extra tiny bit of micro-optimisation; arrays can be marginally faster if you use the indexer / for form - but IIRC believe it dep...
How to get the original value of an attribute in Rails
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Before rails 5.1
Appending _was to your attribute will give you the previous value.
For rails 5.1+
Copied from Lucas Andrade's answer below: https://stackoverflow.com/a/50973808/9359123
Appending _was is deprecated in rails 5.1, now you should ap...
Use 'import module' or 'from module import'?
...eadability: Any name conflicts will show themselves in (unit) testing. But all the names you use from the imported module will be bare, with nary a hint were they come from. I absolutely loathe "import *".
– Jürgen A. Erhard
Dec 26 '09 at 19:59
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