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Fast permutation -> number -> permutation mapping algorithms
I have n elements. For the sake of an example, let's say, 7 elements, 1234567. I know there are 7! = 5040 permutations possible of these 7 elements.
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How can I plot with 2 different y-axes?
I would like superimpose two scatter plots in R so that each set of points has its own (different) y-axis (i.e., in positions 2 and 4 on the figure) but the points appear superimposed on the same figure.
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Converting Dictionary to List? [duplicate]
I'm trying to convert a Python dictionary into a Python list, in order to perform some calculations.
7 Answers
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When to use an object instance variable versus passing an argument to the method
How do you decide between passing arguments to a method versus simply declaring them as object instance variables that are visible to all of the object's methods?
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Difference between null and empty (“”) Java String
What is the difference between null and the "" (empty string)?
22 Answers
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Node.js throws “btoa is not defined” error
In my node.js application I did an npm install btoa-atob so that I could use the btoa() and atob() functions which are native in client-side javascript but for some reason weren't included in node. The new directory showed up in my node_modules folder, which itself is in root alongside app....
Have bash script answer interactive prompts [duplicate]
Is it possible to have a bash script automatically handle prompts that would normally be presented to the user with default actions? Currently I am using a bash script to call an in-house tool that will display prompts to the user (prompting for Y/N) to complete actions, however the script I'm writ...
WordPress is giving me 404 page not found for all pages except the homepage
All of a sudden I go to my WordPress website and all the pages give me a 404 page not found page. I'm assuming the problem lies with the permalink structure, which I could swear I did not touch. The permalink setting is on "month and name."
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EF Migrations: Rollback last applied migration?
This looks like a really common task, but I can't find an easy way to do it.
14 Answers
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How to detect if a stored procedure already exists
I have to write a deployment script which will work if a stored procedure exists or does not exist. i.e. if it exists, then I need to alter it, otherwise create it.
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