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Why are C character literals ints instead of chars?
...y says "Would you disagree with this opinion, which was posted in a past thread discussing the issue in question?" ... and b) It is ludicrous, because a char variable is not an int, so making a character constant be one is a special case. And it's easy to use a character value without promoting it: ...
Avoiding recursion when reading/writing a port synchronously?
...1 can set some global lock state i.e. with a variable (be sure that it's thread safe). locked = true. Then Communication2 can wait until it's unlocked.
loop do
sleep 10ms
break if not locked
end
locked = true
handle_communication()
...
What is the fastest way to create a checksum for large files in C#
...
The problem here is that SHA256Managed reads 4096 bytes at a time (inherit from FileStream and override Read(byte[], int, int) to see how much it reads from the filestream), which is too small a buffer for disk IO.
To speed things up (2 minutes for hashing 2 Gb f...
Local file access with JavaScript
...
If the user selects a file via <input type="file">, you can read and process that file using the File API.
Reading or writing arbitrary files is not allowed by design. It's a violation of the sandbox. From Wikipedia -> Javascript -> Security:
JavaScript and the DOM provide ...
Why does an SSH remote command get fewer environment variables then when run manually? [closed]
...s
startup files. If any of the files exist but cannot be
read, bash reports an error. Tildes are expanded in file
names as described below under Tilde Expansion in the
EXPANSION section.
When bash is invoked as an interactive login shell, or as
...
Reading header data in Ruby on Rails
...ain"
replace "Content-Type" with the name of the header that you want to read.
Update for Rails 4.2
There are 2 ways to get them in Rails 4.2:
Old way (still working):
request.headers["Cookie"]
New way:
request.headers["HTTP_COOKIE"]
To get a Hash with all headers of the request.
reques...
Parse large JSON file in Nodejs
...ave a file which stores many JavaScript objects in JSON form and I need to read the file, create each of the objects, and do something with them (insert them into a db in my case). The JavaScript objects can be represented a format:
...
Convert SVG to PNG in Python
... This is all the code it takes:
with wand.image.Image( blob=svg_file.read(), format="svg" ) as image:
png_image = image.make_blob("png")
I just discovered this today, and felt like it was worth sharing for anyone else who might straggle across this answer as it's been a while since m...
mmap() vs. reading blocks
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I was trying to find the final word on mmap / read performance on Linux and I came across a nice post (link) on the Linux kernel mailing list. It's from 2000, so there have been many improvements to IO and virtual memory in the kernel since then, but it nicely explains ...
python pandas remove duplicate columns
...
It sounds like you already know the unique column names. If that's the case, then df = df['Time', 'Time Relative', 'N2'] would work.
If not, your solution should work:
In [101]: vals = np.random.randint(0,20, (4,3))
vals
Out[101]:
arr...