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Int division: Why is the result of 1/3 == 0?
...se returns the true result of division rounded towards zero. The result of 0.333... is thus rounded down to 0 here. (Note that the processor doesn't actually do any rounding, but you can think of it that way still.)
Also, note that if both operands (numbers) are given as floats; 3.0 and 1.0, or eve...
Can't connect to local MySQL server through socket '/tmp/mysql.sock
...
PratyayPratyay
1,90611 gold badge1313 silver badges1414 bronze badges
...
UIView Hide/Show with animation
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Objective C
[UIView transitionWithView:button
duration:0.4
options:UIViewAnimationOptionTransitionCrossDissolve
animations:^{
button.hidden = YES;
}
completion:NULL];
Swift
UIView.transitio...
MySql: Tinyint (2) vs tinyint(1) - what is the difference?
...4) zerofill
both columns has the value of 1, output for column A would be 01 and 0001 for B, as seen in screenshot below :)
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Implement Stack using Two Queues
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Richard
40.9k2222 gold badges134134 silver badges203203 bronze badges
answered Mar 27 '09 at 2:17
SvanteSvante...
Standard deviation of a list
...
Since Python 3.4 / PEP450 there is a statistics module in the standard library, which has a method stdev for calculating the standard deviation of iterables like yours:
>>> A_rank = [0.8, 0.4, 1.2, 3.7, 2.6, 5.8]
>>> import statis...
Python matplotlib multiple bars
...lotlib.dates import date2num
import datetime
x = [
datetime.datetime(2011, 1, 4, 0, 0),
datetime.datetime(2011, 1, 5, 0, 0),
datetime.datetime(2011, 1, 6, 0, 0)
]
x = date2num(x)
y = [4, 9, 2]
z = [1, 2, 3]
k = [11, 12, 13]
ax = plt.subplot(111)
ax.bar(x-0.2, y, width=0.2, color='b', ...
Can I add jars to maven 2 build classpath without installing them?
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605
Problems of popular approaches
Most of the answers you'll find around the internet will suggest...
Pandas get topmost n records within each group
...
>>> df.groupby('id').head(2)
id value
id
1 0 1 1
1 1 2
2 3 2 1
4 2 2
3 7 3 1
4 8 4 1
(Keep in mind that you might need to order/sort before, depending on your data)
EDIT: As mentioned by the questioner, use df.gro...
Nested JSON objects - do I have to use arrays for everything?
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204
You don't need to use arrays.
JSON values can be arrays, objects, or primitives (numbers or st...