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Why do I name projects with a website in the path?

If your package has the exact same import path as someone else's package, then someone will have a hard time trying to use both packages in the same project because the import paths are not unique. So long as everyone uses a string equal to a URL that they effectively "own", such as your GitHub account (or actually own, such as your own domain), then these name collisions will not occur (excepting the fact that ownership of URLs may change over time).

It also makes it easier to go get your project, since the host location is part of the import string. Every source file that uses the package also tells you where to get it from. That is a nice property to have.

Where do I initialize git?

Your project should have some root folder that contains everything in the project, and nothing outside of the project. Initialize git in this directory. It's also common to initialize your Go module here, if it's a Go project.

You may be restricted on where to put the git root by where you're trying to host the code. For example, if hosting on GitHub, all of the code you push has to go inside a repository. This means that you can put your git root in a higher directory that contains all your repositories, but there's no way (that I know of) to actually push this to the remote. Remember that your local file system is not the same as the remote host's. You may have a local folder called github.com/myname/, but that doesn't mean that the remote end supports writing files to such a location.

There is a difference between a file and a file descriptor (FD).

All processes share the same files. They don't necessarily have access to the same files, and a file is not its name, either; two different processes which open the same name might not actually open the same file, for example if the first file were renamed or unlinked and a new file were associated with the name. But if they do open the same file, it's necessarily shared, and changes will be mutually visible.

But a file descriptor is not a file. It refers to a file (not a filename, see above), but it also contains other information, including a file position used for and updated by calls to read and write. (You can use "positioned" read and write, pread and pwrite, if you don't want to use the position in the FD.) File descriptors are shared between parent and child processes, and so the file position in the FD is also shared.

Another thing stored in the file descriptor (in the kernel, where user processes can't get at it) is the list of permitted actions (on Unix, read, write, and/or execute, and possibly others). Permissions are stored in the file directory, not in the file itself, and the requested permissions are copied into the file descriptor when the file is opened (if the permissions are available.) It's possible for a child process to have a different user or group than the parent, particularly if the parent is started with augmented permissions but drops them before spawning the child. A file descriptor for a file opened in this manner still has the same permissions uf it is shared with a child, even if the child would itself be able to open the file.

Here is a way using tidyverse.

We can make use of where within across to select the columns with logical short-circuit expression where we check

1. the columns are numeric - (is.numeric)
2. if the 1 is TRUE, check whether number of distinct elements less than the user defined n
3. if 2 is TRUE, then check all the unique elements in the column are 0 and 1
4. loop over those selected column and convert to factor class

select() can set a timeout for the connection part.

Yes, but only if you put the socket into non-blocking mode before calling connect(), so that connect() exits immediately and then the code can use select() to wait for the socket to report when the connect operation has finished. But the code shown is not doing that.

setsockopt() with timeval can timeout the receiving portion of the code

Yes, though select() can also be used to timeout a read operation, as well. Simply call select() first, and then call recv() only if select() reports that the socket is readable (has pending data to read).

Try something like this:

You're supposed to free memory right after the last time it will be used. In your program, after the while loop in recursion, Energy isn't used again, so you should free it right after that (i.e., right before return event_counter;).

I think you need something like this:

There is no public interface in the Magnification API that allows clients to apply filtering (other than color transforms). This used to be possible, but the MagSetImageScalingCallback API was deprecated in Windows 7:

This function works only when Desktop Window Manager (DWM) is off.

Even if it is still available, it will no longer work as designed. From Desktop Window Manager is always on:

In Windows 8, Desktop Window Manager (DWM) is always ON and cannot be disabled by end users and apps.

With that, you're pretty much out of luck trying to replicate the results of the Magnifier application's upscaler using the Magnification API.

The Magnifier application appears to be using undocumented API calls to accomplish the upscaling effects. Running dumpbin /IMPORTS magnify.exe | findstr "Mag" lists some of the public APIs, as well as the following:

• MagSetLensUseBitmapSmoothing
• MagSetFullscreenUseBitmapSmoothing

Unless you are willing to reverse-engineer those API calls, you're going to have to spend your time on another project, or look into a different solution.

A note on the upscaling algorithm: If you look closely you'll notice that the upscaled image doesn't exhibit any of the artifacts associated with smoothing algorithms.

The image isn't blurred in any way. Instead, it shows sharp edges everywhere. I don't know what upscaling algorithm is at work here. Wikipedia's entry on Pixel-art scaling algorithms lists some that have very similar properties. It might well be one of those, or a modified version thereof.

There are multiple ways. The easiest one will be to use split.

Move the CASE expression to the WHERE clause: