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How to make good reproducible pandas examples
...search (search the docs, search StackOverflow), give a summary:
The docstring for sum simply states "Compute sum of group values"
The groupby docs don't give any examples for this.
Aside: the answer here is to use df.groupby('A', as_index=False).sum().
if it's relevant that you have Times...
How to access component methods from “outside” in ReactJS?
... 2016-09-19: Changed example to use ref callback per guidance from the ref String attribute docs.
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convert a list of objects from one type to another using lambda expression
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List<char> c = new List<char>() { 'A', 'B', 'C' };
List<string> s = c.Select(x => x.ToString()).ToList();
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What is a covariant return type?
...ter Java5 welcome to covariant return type");
}
public static void main(String args[]){
new Two().get().message();
}
}
Before Java 5, it was not possible override any method
by changing the return type. But now, since Java5,
it is possible to override method by changing the return ...
Can jQuery read/write cookies to a browser?
...okies is easy, but reading them is sort of a pain, since you have to split strings and stuff. If you're already using JQuery, then the cookie plugin could be nice...... An annoying thing about reading cookies is that some browsers remove the final semicolon and some don't.... nice to have someone el...
How can I add a class to a DOM element in JavaScript?
...ame = "aClassName1 aClassName2"; its just an attribute, you can assign any string you like, even if it makes for invalid html
– Darko Z
Apr 29 '14 at 9:47
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How to do a logical OR operation in shell scripting
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else
echo "bar"
fi
I don't think sh supports "==". Use "=" to compare strings and -eq to compare ints.
man test
for more details.
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How to set tint for an image view programmatically in android?
...r types of resources, such as integers, bools, dimensions, etc. Except for string, for which you can directly use getString() in your Activity without the need to first call getResources() (don't ask me why).
Otherwise, your code looks good. (Though I haven't investigated the setColorFilter method ...
Deleting an object in java?
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If you want help an object go away, set its reference to null.
String x = "sadfasdfasd";
// do stuff
x = null;
Setting reference to null will make it more likely that the object will be garbage collected, as long as there are no other references to the object.
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not None test in Python [duplicate]
...ence, you are not able to test if the variable was set to None or an empty string.
– Ethan
Aug 30 '13 at 1:02
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