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R object identification
I am often ending up with a function producing output for which I don't understand the output data type. I'm expecting a list and it ends up being a list of lists or a data frame or something else. What's a good method or workflow for figuring out the output data type when first using a function?
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How can I do division with variables in a Linux shell?
When I run commands in my shell as below, it returns an expr: non-integer argument error. Can someone please explain this to me?
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Difference between rake db:migrate db:reset and db:schema:load
The difference between rake db:migrate and rake db:reset is pretty clear in my head. The thing which I don't understand is how rake db:schema:load different from the former two.
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Creating Threads in python
I have a script and I want one function to run at the same time as the other.
6 Answers
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Git: Discard all changes on a diverged local branch
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How to parse a CSV file in Bash?
I'm working on a long Bash script. I want to read cells from a CSV file into Bash variables. I can parse lines and the first column, but not any other column. Here's my code so far:
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How to work with complex numbers in C?
How can I work with complex numbers in C? I see there is a complex.h header file, but it doesn't give me much information about how to use it. How to access real and imaginary parts in an efficient way? Is there native functions to get module and phase?
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Java Enum Methods - return opposite direction enum
I would like to declare an enum Direction, that has a method that returns the opposite direction (the following is not syntactically correct, i.e, enums cannot be instantiated, but it illustrates my point). Is this possible in Java?
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What's the role of adapters in Android?
I want to know when , where and how adapters are used in the context of Android.
10 Answers
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How to drop columns by name in a data frame
I have a large data set and I would like to read specific columns or drop all the others.
11 Answers
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