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Difference between Big-O and Little-O Notation
What is the difference between Big-O notation O(n) and Little-O notation o(n) ?
4 Answers
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What is the difference between class and instance attributes?
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Only the mutable types are shared. Like for int and str they still attached with each instances rather than class.
– Babu
Jul 17 '14 at 11:59
11
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How to “test” NoneType in python?
...ariable has None in it or not.
Quoting from is docs,
The operators is and is not test for object identity: x is y is true if and only if x and y are the same object. x is not y yields the inverse truth value.
Since there can be only one instance of None, is would be the preferred way to check...
Use rvmrc or ruby-version file to set a project gemset with RVM?
I use RVM, the Ruby Version Manager to specify a Ruby version and a set of gems for each of my Rails projects.
5 Answers
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How do I tell if a regular file does not exist in Bash?
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The test command ([ here) has a "not" logical operator which is the exclamation point (similar to many other languages). Try this:
if [ ! -f /tmp/foo.txt ]; then
echo "File not found!"
fi
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“x not in y” or “not x in y”
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They always give the same result.
In fact, not 'ham' in 'spam and eggs' appears to be special cased to perform a single "not in" operation, rather than an "in" operation and then negating the result:
>>> import dis
>>> def notin():
'ham' not in 'spam and eggs'
&g...
Distributed sequence number generation?
...m first seeing now.
You'll need to differentiate between sequence numbers and unique IDs that are (optionally) loosely sortable by a specific criteria (typically generation time). True sequence numbers imply knowledge of what all other workers have done, and as such require shared state. There is n...
What is the difference between “JPG” / “JPEG” / “PNG” / “BMP” / “GIF” / “TIFF” Image?
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Yes. They are different file formats (and their file extensions).
Wikipedia entries for each of the formats will give you quite a bit of information:
JPEG (or JPG, for the file extension; Joint Photographic Experts Group)
PNG (Portable Network Graphics)
BMP (B...
Why can't an anonymous method be assigned to var?
...to be the default instead of Predicate or Action or any other possibility? And, for lambdas, why is it obvious that the intention is to choose the delegate form, rather than the expression tree form?
But we could say that Func is special, and that the inferred type of a lambda or anonymous method i...
Determine if two rectangles overlap each other?
...akes the following inputs from the user to construct rectangles (between 2 and 5): height, width, x-pos, y-pos. All of these rectangles will exist parallel to the x and the y axis, that is all of their edges will have slopes of 0 or infinity.
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