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How do I implement basic “Long Polling”?
...
<style type="text/css" media="screen">
body{ background:#000;color:#fff;font-size:.9em; }
.msg{ background:#aaa;padding:.2em; border-bottom:1px #000 solid}
.old{ background-color:#246499;}
.new{ background-color:#3B9957;}
.error{ background-color:#992E36;}
...
pandas: How do I split text in a column into multiple rows?
...lution:
time python -c "import pandas as pd;
df = pd.DataFrame(['a b c']*100000, columns=['col']);
print df['col'].apply(lambda x : pd.Series(x.split(' '))).head()"
... compared to this alternative:
time python -c "import pandas as pd;
from scipy import array, concatenate;
df = pd.DataFrame(['a ...
Technically, why are processes in Erlang more efficient than OS threads?
...y, making it an O(1) operation.
To switch OS threads, it takes about 500-1000 nanoseconds, because you're calling down to the kernel. The OS thread scheduler might run in O(log(n)) or O(log(log(n))) time, which will start to be noticeable if you have tens of thousands, or even millions of threads....
Structs versus classes
I'm about to create 100,000 objects in code. They are small ones, only with 2 or 3 properties. I'll put them in a generic list and when they are, I'll loop them and check value a and maybe update value b .
...
What is the difference between `sorted(list)` vs `list.sort()`?
...s our setup:
import timeit
setup = """
import random
lists = [list(range(10000)) for _ in range(1000)] # list of lists
for l in lists:
random.shuffle(l) # shuffle each list
shuffled_iter = iter(lists) # wrap as iterator so next() yields one at a time
"""
And here's our results for a list of ...
Why not use Double or Float to represent currency?
... do
you have left?
System.out.println(1.03 - .42);
prints out 0.6100000000000001.
The right way to solve this problem is
to use BigDecimal, int or long
for monetary calculations.
Though BigDecimal has some caveats (please see currently accepted answer).
...
Extending an Object in Javascript
...value.indexOf('MWh')) return this._powerConsumption = value.replace('M', ',000k')
this._powerConsumption = value
throw new Error('Power consumption format not recognised.')
}
}
})
const newRobot = Object.create(Robot)
newRobot.powerConsumption = '5MWh'
console...
Quickest way to convert a base 10 number to any base in .NET?
... methods are faster than any others posted so far. I was able to convert 1,000,000 numbers from and to base 36 in under 400ms in a single core machine.
Example below is for base 62. Change the BaseChars array to convert from and to any other base.
private static readonly char[] BaseChars =
...
Why is Go so slow (compared to Java)?
...o 3.89 369,380 1229 8.29 43% 53% 61% 82%
C gcc 2.43 339,000 2579 5.68 46% 70% 51% 72%
fannkuch-redux
1.72x
Go 15.59 952 900 62.08 100% 100% 100% 100%
C gcc 9.07 1,576 910 35.43 100% 99% 98% 94%
spectral-norm
2x
Go 3.96 2,412 548 15.73 99% 99% ...
android button selector
...="@color/selected"/>
<padding />
<stroke android:color="#000" android:width="1dp"/>
<corners android:bottomRightRadius="15dp" android:bottomLeftRadius="15dp" android:topLeftRadius="15dp" android:topRightRadius="15dp"/>
</shape>
Create unselected.xml shape in dra...