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Multiple aggregations of the same column using pandas GroupBy.agg()
Is there a pandas built-in way to apply two different aggregating functions f1, f2 to the same column df["returns"] , without having to call agg() multiple times?
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FIND_IN_SET() vs IN()
I have 2 tables in my database. One is for orders, and one is for companies.
6 Answers
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Haversine Formula in Python (Bearing and Distance between two GPS points)
I would like to know how to get the distance and bearing between 2 GPS points .
I have researched on the haversine formula.
Someone told me that I could also find the bearing using the same data.
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How do I wait for an asynchronously dispatched block to finish?
I am testing some code that does asynchronous processing using Grand Central Dispatch. The testing code looks like this:
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Can I use a min-height for table, tr or td?
I am trying to show some details of a receive in a table.
7 Answers
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How to shrink/purge ibdata1 file in MySQL
I am using MySQL in localhost as a "query tool" for performing statistics in R, that is, everytime I run a R script, I create a new database (A), create a new table (B), import the data into B, submit a query to get what I need, and then I drop B and drop A.
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Comparing date ranges
In MySQL, If I have a list of date ranges (range-start and range-end). e.g.
10 Answers
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Polymorphism vs Overriding vs Overloading
In terms of Java, when someone asks:
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How to develop and test an app that sends emails (without filling someone's mailbox with test data)?
I have a lot of apps that send email. Sometimes it's one or two messages at a time. Sometimes it's thousands of messages.
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Compile time string hashing
I have read in few different places that using C++11's new string literals it might be possible to compute a string's hash at compile time. However, no one seems to be ready to come out and say that it will be possible or how it would be done.
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