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What is pseudopolynomial time? How does it differ from polynomial time?
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To understand the difference between polynomial time and pseudopolynomial time, we need to start off by formalizing what "polynomial time" means.
The common intuition for polynomial time is "time O(nk) for some k." For example, select...
adding directory to sys.path /PYTHONPATH
...documented as normally coming after the working directory but before the standard interpreter-supplied paths. sys.path.append() appends to the existing path. See here and here. If you want a particular directory to come first, simply insert it at the head of sys.path:
import sys
sys.path.insert(...
How to list active / open connections in Oracle?
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Error starting at line 1 in command: select * from FROM v$session Error at Command Line:1 Column:14 Error report: SQL Error: ORA-00903: invalid table name 00903. 00000 - "invalid table name" *Cause: *Action:
– pistacchio
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How do I request a file but not save it with Wget? [closed]
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Use q flag for quiet mode, and tell wget to output to stdout with O- (uppercase o) and redirect to /dev/null to discard the output:
wget -qO- $url &> /dev/null
> redirects application output (to a file). if > is preceded by ampersand, sh...
Python function attributes - uses and abuses [closed]
Not many are aware of this feature, but Python's functions (and methods) can have attributes . Behold:
8 Answers
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JavaScript: Object Rename Key
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The most complete (and correct) way of doing this would be, I believe:
if (old_key !== new_key) {
Object.defineProperty(o, new_key,
Object.getOwnPropertyDescriptor(o, old_key));
delete o[old_key];
}
This method ensures that t...
Rolling or sliding window iterator?
...m,)
yield result
The one from the docs is a little more succinct and uses itertools to greater effect I imagine.
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How to jump to a particular line in a huge text file?
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MiniQuark, I tried it, it actually works, and really quickly. I'll need to see what happens if I work on a dozen of files at the same time this way, find out at what point my system dies.
– user63503
Mar 6 '09 at 22:46
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sed command with -i option (in-place editing) works fine on Ubuntu but not Mac [duplicate]
I know nothing about Sed but need this command (which works fine on Ubuntu) to work on a Mac OSX:
4 Answers
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What's the canonical way to check for type in Python?
... str (exclude subclasses):
if type(o) is str:
The following also works, and can be useful in some cases:
if issubclass(type(o), str):
See Built-in Functions in the Python Library Reference for relevant information.
One more note: in this case, if you're using Python 2, you may actually want t...