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Count number of rows within each group
I have a dataframe and I would like to count the number of rows within each group. I reguarly use the aggregate function to sum data as follows:
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Best practices for API versioning? [closed]
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This is a good and a tricky question. The topic of URI design is at the same time the most prominent part of a REST API and, therefore, a potentially long-term commitment towards the users of that API.
Since evolution of an application and...
Understanding generators in Python
I am reading the Python cookbook at the moment and am currently looking at generators. I'm finding it hard to get my head round.
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Getting distance between two points based on latitude/longitude
I tried implementing this formula: http://andrew.hedges.name/experiments/haversine/
The aplet does good for the two points I am testing:
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IE9 border-radius and background gradient bleeding
IE9 is apparently able to handle rounded corners by using the CSS3 standard definition of border-radius .
17 Answers
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Can you explain the HttpURLConnection connection process?
... a web service. I know how to use HTTPURLConnection but I want to understand how it works. Basically, I want to know the following:
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Add margin above top ListView item (and below last) in Android
This is a pretty fine question about the layout of items in a ListView in Android.
5 Answers
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How do I reverse an int array in Java?
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And I would like to put validData.length / 2 part to the outside of the for-loop.
– Jin Kwon
Mar 10 '14 at 3:28
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Does PHP have threading?
... found this PECL package called threads , but there is not a release yet. And nothing is coming up on the PHP website.
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How can I change the version of npm using nvm?
...S for my node work. It works totally fine for installing separate versions and switching between them. It also installs the latest version of NPM within each local .../bin folder along with the node binary. However, there doesn't seem to be any way to switch the version of NPM that I'm using (or at ...