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Remove rows with duplicate indices (Pandas DataFrame and TimeSeries)
...he index as a dataframe column, drops duplicates on that, then removes the new column:
df = df.reset_index().drop_duplicates(subset='index', keep='last').set_index('index').sort_index()
Note that the use of .sort_index() above at the end is as needed and is optional.
...
Why does “_” (underscore) match “-” (hyphen)?
...unction () {
StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fstackoverflow.com%2fquestions%2f8236818%2fwhy-does-underscore-match-hyphen%23new-answer', 'question_page');
}
);
...
Missing return statement in a non-void method compiles
... stub-methods like:
IEnumerator IEnumerable.GetEnumerator()
{
throw new NotImplementedException();
}
That's a non-void method. It has to be a non-void method in order to satisfy the interface. But it seems silly to make this implementation illegal because it does not return anything.
Tha...
Prefer composition over inheritance?
... this.person = p;
this.Salary = salary;
}
}
Person johnny = new Person ("Mr.", "John", 25);
Employee john = new Employee (johnny, 50000);
Composition is typically "has a" or "uses a" relationship. Here the Employee class has a Person. It does not inherit from Person but instead gets...
What is the difference between 'git pull' and 'git fetch'?
...tory. Everyone always says "DVCS" when describing Git, but as a relatively new programmer, that means nothing to me. I've never seen a CVCS, and I've also never not worked with a cental remote repository when collaborating with others (i.e. Github), so until now I've yet to understand what made Git ...
What is the difference between HTML tags and ?
...hange their color in my stylesheet.
Also note that HTML5 includes a broad new set of elements that define common page structures, such as article, section, nav, etc.
Section 4.4 of the HTML 5 working draft lists them and gives hints as to their usage. HTML5 is still a working spec, so nothing i...
How would you implement an LRU cache in Java?
...dHashMap and Collections#synchronizedMap , but I'm curious if any of the new concurrent collections would be better candidates.
...
Getting the current Fragment instance in the viewpager
... 0 && page != null) {
((FragmentClass1)page).updateList("new item");
}
return true;
Please rethink your variable naming convention, using as the variable name the name of the class is very confusing(so no ViewPager ViewPager, use ViewPager mPager for example).
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How to vertically align an image inside a div
...
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It seems like you also need to add "white-space: nowrap;" to the frame or you will run into an issue if you have line break between your im...
Parse large JSON file in Nodejs
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Kevin B
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answered Aug 8 '12 at 23:26
josh3736josh3736
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