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Load multiple packages at once
...dplyr, psych, tm)
and if the package is missing p_load will download it from CRAN or Bioconductor.
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throwing exceptions out of a destructor
... fails... There is really no good way to protect against exceptions thrown from destructors, so the library makes no guarantees if an element destructor throws" (from Appendix E3.2) .
...
Setting Environment Variables for Node to retrieve
...credentials to your application. USER_ID and USER_KEY can both be accessed from process.env.USER_ID and process.env.USER_KEY respectively. You don't need to edit them, just access their contents.
It looks like they are simply giving you the choice between loading your USER_ID and USER_KEY from eith...
Example images for code and mark-up Q&As [closed]
...
Here are some example images for common use, mostly from existing answers on SO.
Icons
Simple Geometric shapes generated using Java as originally seen in this answer. It includes a Java based interface that defines the URLs and makes them easy to access.
Details: 32x32 p...
How to un-submodule a Git submodule?
...Could you please explain which part of the above commands causes the files from the submodule to end up in the subdirectory? Is it that you when you do the merge git brings in the file in the top level directory (with its history) but when you do the git add submodule_path it implicity does a git mv...
Python script to copy text to clipboard [duplicate]
...
See Pyperclip. Example (taken from Pyperclip site):
import pyperclip
pyperclip.copy('The text to be copied to the clipboard.')
spam = pyperclip.paste()
Also, see Xerox. But it appears to have more dependencies.
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When is it practical to use Depth-First Search (DFS) vs Breadth-First Search (BFS)? [closed]
... of solutions (aka searched-for items).
If you know a solution is not far from the root of the tree, a
breadth first search (BFS) might be better.
If the tree is very deep and solutions are rare, depth first search
(DFS) might take an extremely long time, but BFS could be faster.
If the tree is v...
Loading cross-domain endpoint with AJAX
... to the same origin policy; the request can not successfully retrieve data from a different domain, subdomain, port, or protocol.
Script and JSONP requests are not subject to the same origin policy restrictions.
There are some ways to overcome the cross-domain barrier:
CORS Proxy Alternatives
Wa...
Attach a file from MemoryStream to a MailMessage in C#
...ted,Values,...");
writer.Flush();
stream.Position = 0; // read from the start of what was written
message.Attachments.Add(new Attachment(stream, "filename.csv", "text/csv"));
mailClient.Send(message);
}
The StreamWriter and underlying stream should not be disposed until after...
Stripping everything but alphanumeric chars from a string in Python
What is the best way to strip all non alphanumeric characters from a string, using Python?
11 Answers
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