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Formatting Decimal places in R
I have a number, for example 1.128347132904321674821 that I would like to show as only two decimal places when output to screen (or written to a file). How does one do that?
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Call apply-like function on each row of dataframe with multiple arguments from each row
I have a dataframe with multiple columns. For each row in the dataframe, I want to call a function on the row, and the input of the function is using multiple columns from that row. For example, let's say I have this data and this testFunc which accepts two args:
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How can I select from list of values in SQL Server
I have very simple problem that I can't solve. I need to do something like this:
13 Answers
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How do I convert an existing callback API to promises?
I want to work with promises but I have a callback API in a format like:
20 Answers
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Why do I need 'b' to encode a string with Base64?
Following this python example , I encode a string as Base64 with:
5 Answers
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Way to go from recursion to iteration
I've used recursion quite a lot on my many years of programming to solve simple problems, but I'm fully aware that sometimes you need iteration due to memory/speed problems.
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jquery .html() vs .append()
Lets say I have an empty div:
8 Answers
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How do you copy the contents of an array to a std::vector in C++ without looping?
I have an array of values that is passed to my function from a different part of the program that I need to store for later processing. Since I don't know how many times my function will be called before it is time to process the data, I need a dynamic storage structure, so I chose a std::vector ....
Do I need to convert .CER to .CRT for Apache SSL certificates? If so, how?
I need to setup an Apache 2 server with SSL.
10 Answers
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Does Java casting introduce overhead? Why?
Is there any overhead when we cast objects of one type to another? Or the compiler just resolves everything and there is no cost at run time?
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