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Are there any O(1/n) algorithms?
...he following one:
def get_faster(list):
how_long = (1 / len(list)) * 100000
sleep(how_long)
Clearly, this function spends less time as the input size grows … at least until some limit, enforced by the hardware (precision of the numbers, minimum of time that sleep can wait, time to proce...
UIView Hide/Show with animation
...
Objective C
[UIView transitionWithView:button
duration:0.4
options:UIViewAnimationOptionTransitionCrossDissolve
animations:^{
button.hidden = YES;
}
completion:NULL];
Swift
UIView.transitio...
Draw in Canvas by finger, Android
...
+200
Start By going through the Fingerpaint demo in the sdk sample.
Another Sample:
public class MainActivity extends Activity {
D...
Multiple dex files define Landroid/support/v4/accessibilityservice/AccessibilityServiceInfoCompat
...
305
Run gradle -q dependencies (or gradle -q :projectName:dependencies) to generate a dependency re...
How do I iterate over an NSArray?
...d idiom to iterate over an NSArray. My code needs to be suitable for OS X 10.4+.
8 Answers
...
Python list iterator behavior and next(iterator)
...tion to i being printed each iteration:
>>> a = iter(list(range(10)))
>>> for i in a:
... print(i)
... next(a)
...
0
1
2
3
4
5
6
7
8
9
So 0 is the output of print(i), 1 the return value from next(), echoed by the interactive interpreter, etc. There are just 5 iterations, ...
Why am I seeing “TypeError: string indices must be integers”?
...
answered May 20 '11 at 21:16
TamásTamás
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...
Convert integer into its character equivalent, where 0 => a, 1 => b, etc
... lower case letters:
var chr = String.fromCharCode(97 + n); // where n is 0, 1, 2 ...
97 is the ASCII code for lower case 'a'. If you want uppercase letters, replace 97 with 65 (uppercase 'A'). Note that if n > 25, you will get out of the range of letters.
...
How to access pandas groupby dataframe by key
...group method:
In [21]: gb.get_group('foo')
Out[21]:
A B C
0 foo 1.624345 5
2 foo -0.528172 11
4 foo 0.865408 14
Note: This doesn't require creating an intermediary dictionary / copy of every subdataframe for every group, so will be much more memory-efficient that creating...