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cartesian product in pandas
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If you have a key that is repeated for each row, then you can produce a cartesian product using merge (like you would in SQL).
from pandas import DataFrame, merge
df1 = DataFrame({'key':[1,1], 'col1':[1,2],'col2':[3,4]})
df2 = DataFrame({'key':[1,1], 'col3':[...
Why is setTimeout(fn, 0) sometimes useful?
...consistently winning this race and attempting to set drop-down selection before the browser was ready, meaning that the bug would appear.
This race existed because JavaScript has a single thread of execution that is shared with page rendering. In effect, running JavaScript blocks the updating of th...
Check play state of AVPlayer
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To get notification for reaching the end of an item (via Apple):
[[NSNotificationCenter defaultCenter]
addObserver:<self>
selector:@selector(<#The selector name#>)
name:AVPlayerItemDidPlayToEndTimeNotification
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registerForRemoteNotificationTypes: is not supported in iOS 8.0 and later
When trying to register for push notifications under iOS 8.x:
15 Answers
15
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Should you choose the MONEY or DECIMAL(x,y) datatypes in SQL Server?
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"Never" is a strong word. "Money" is useful for casting results to that type for display to the user in a culture-sensitive way, but you're right that it's very bad to use for the calculations itself.
– Joel Coehoorn
Feb 24 '09 at...
Full Screen DialogFragment in Android
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And for me, I needed to use a RelativeLayout, but the dialog width wasn't adjusting properly to the contents, so I nested the RelativeLayout in a LinearLayout whose only child was the RelativeLayout... this triggered the proper w...
PostgreSQL: How to pass parameters from command line?
..., you can PREPARE statements just like you can in a scripting language. Unfortunately, you still can't use ?, but you can use $n notation.
Using the above example:
PREPARE foo(text,text,text) AS
SELECT *
FROM foobar
WHERE foo = $1
AND bar = $2
OR baz = $3 ;
EXEC...
Django REST Framework: adding additional field to ModelSerializer
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I think SerializerMethodField is what you're looking for:
class FooSerializer(serializers.ModelSerializer):
my_field = serializers.SerializerMethodField('is_named_bar')
def is_named_bar(self, foo):
return foo.name == "bar"
class Meta:
model = Foo
fields ...
How do I create a slug in Django?
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SlugFields set db_index=True by default, and also use a form field by default that has a validation regex to require valid slugs (if represented in a ModelForm or in the admin). You can do those things manually with a CharField if you prefer, it just makes the intention of your c...
Regex using javascript to return just numbers
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@Onza you are missing the backslash before the d, so .match(/\d+/g)
– meder omuraliev
Jun 20 '16 at 16:40
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