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Combining two Series into a DataFrame in pandas
I have two Series s1 and s2 with the same (non-consecutive) indices. How do I combine s1 and s2 to being two columns in a DataFrame and keep one of the indices as a third column?
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Can I create a One-Time-Use Function in a Script or Stored Procedure?
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You can call CREATE Function near the beginning of your script and DROP Function near the end.
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Add a property to a JavaScript object using a variable as the name?
I'm pulling items out of the DOM with jQuery and want to set a property on an object using the id of the DOM element.
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Convert datetime object to a String of date only in Python
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date and datetime objects (and time as well) support a mini-language to specify output, and there are two ways to access it:
direct method call: dt.strftime('format here'); and
new format method: '{:format here}'.format(dt)
So...
Return None if Dictionary key is not available
... situations like this. You supply a factory method that takes no arguments and creates a value when it sees a new key. It's more useful when you want to return something like an empty list on new keys (see the examples).
from collections import defaultdict
d = defaultdict(lambda: None)
print d['new...
How do you reference a capture group with regex find and replace in Visual Studio 2012, 2013, 2015,
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To find and replace in VS 2012 and VS 2015 you do the following:
Surround with (), display capture with $1, $2, $n
Example (thanks to syonip)
In the find options, make sure 'use regular expressions' is checked, and put the follo...
std::unique_lock or std::lock_guard?
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The difference is that you can lock and unlock a std::unique_lock. std::lock_guard will be locked only once on construction and unlocked on destruction.
So for use case B you definitely need a std::unique_lock for the condition variable. In case A it depends ...
How to retry after exception?
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Do a while True inside your for loop, put your try code inside, and break from that while loop only when your code succeeds.
for i in range(0,100):
while True:
try:
# do stuff
except SomeSpecificException:
continue
break
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What is lexical scope?
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I understand them through examples. :)
First, lexical scope (also called static scope), in C-like syntax:
void fun()
{
int x = 5;
void fun2()
{
printf("%d", x);
}
}
Every inner level can access its outer l...
How to set a Django model field's default value to a function call / callable (e.g., a date relative
...e class.
PRE Django 1.7
Django lets you pass a callable as the default, and it will invoke it each time, just as you want:
from datetime import datetime, timedelta
class MyModel(models.Model):
# default to 1 day from now
my_date = models.DateTimeField(default=lambda: datetime.now() + timedel...