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What is the main difference between Inheritance and Polymorphism?
...tion in an end of module open book exam today and found myself lost. I was reading Head first Java and both definitions seemed to be exactly the same. I was just wondering what the MAIN difference was for my own piece of mind. I know there are a number of similar questions to this but, none I have ...
How to read the database table name of a Model instance?
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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
...
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:
...
Why do I get a segmentation fault when writing to a “char *s” initialized with a string literal, but
...d, static array of characters,
and this unnamed array may be stored
in read-only memory, and which
therefore cannot necessarily be
modified. In an expression context,
the array is converted at once to a
pointer, as usual (see section 6), so
the second declaration initializes p
to poi...
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...
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...
Local Storage vs Cookies
...kies and local storage serve different purposes. Cookies are primarily for reading server-side, local storage can only be read by the client-side. So the question is, in your app, who needs this data — the client or the server?
If it's your client (your JavaScript), then by all means switch. You'...
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...