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Remove columns from dataframe where ALL values are NA
I'm having trouble with a data frame and couldn't really resolve that issue myself:
The dataframe has arbitrary properties as columns and each row represents one data set .
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What's the difference between a word and byte?
I've done some research.
A byte is 8 bits and a word is the smallest unit that can be addressed on memory. The exact length of a word varies. What I don't understand is what's the point of having a byte? Why not say 8 bits?
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Coding Practices which enable the compiler/optimizer to make a faster program
Many years ago, C compilers were not particularly smart. As a workaround K&R invented the register keyword, to hint to the compiler, that maybe it would be a good idea to keep this variable in an internal register. They also made the tertiary operator to help generate better code.
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How can I scan barcodes on iOS?
How can I simply scan barcodes on iPhone and/or iPad?
19 Answers
19
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IIS7 Permissions Overview - ApplicationPoolIdentity
We have recently upgraded to IIS7 as a core web server and I need an overview in terms of the permissions. Previously, when needing to write to the file system I would have give the AppPool user (Network Service) access to the directory or file.
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Why does changing the sum order returns a different result?
Why does changing the sum order returns a different result?
6 Answers
6
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Batch file. Delete all files and folders in a directory
I want to have a batch file that will delete all the folders and files in my cache folder for my wireless toolkit.
15 Answe...
htaccess Access-Control-Allow-Origin
I'm creating a script that loads externally on other sites. It loads CSS and HTML and works fine on my own servers.
9 Answe...
What is a Java ClassLoader?
In a few simple sentences, what is a Java ClassLoader, when is it used and why?
7 Answers
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How do I convert between big-endian and little-endian values in C++?
How do I convert between big-endian and little-endian values in C++?
31 Answers
31
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