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How to reliably open a file in the same directory as a Python script
...th(
os.path.join(os.getcwd(), os.path.dirname(__file__)))
The join() call prepends the current working directory, but the documentation says that if some path is absolute, all other paths left of it are dropped. Therefore, getcwd() is dropped when dirname(__file__) returns an absolute path.
Als...
What does $_ mean in PowerShell?
...
This is the variable for the current value in the pipe line, which is called $PSItem in Powershell 3 and newer.
1,2,3 | %{ write-host $_ }
or
1,2,3 | %{ write-host $PSItem }
For example in the above code the %{} block is called for every value in the array. The $_ or $PSItem variable ...
Short description of the scoping rules?
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Actually, a concise rule for Python Scope resolution, from Learning Python, 3rd. Ed.. (These rules are specific to variable names, not attributes. If you reference it without a period, these rules apply.)
LEGB Rule
Local — N...
How to implement a queue with three stacks?
...r Sedgewick have confirmed they are not aware of a 3-stack solution within all the constraints of the original question
DETAILS
There are two implementations behind this link: http://www.eecs.usma.edu/webs/people/okasaki/jfp95/index.html
One of them is O(1) with three stacks BUT it uses lazy exe...
Remove all occurrences of a value from a list?
...on over the filter+lambda; the former is more readable in addition to generally more efficient.
– habnabit
Jul 21 '09 at 4:28
17
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Is arr.__len__() the preferred way to get the length of an array in Python?
...ples:
my_tuple = (1,2,3,4,5)
len(my_tuple)
# 5
And strings, which are really just arrays of characters:
my_string = 'hello world'
len(my_string)
# 11
It was intentionally done this way so that lists, tuples and other container types or iterables didn't all need to explicitly implement a public...
split string only on first instance of specified character
...Very elegant. Works like a charm. Thank you.
– Ofeargall
Jan 5 '11 at 18:43
12
Just to be clear, ...
Why does += behave unexpectedly on lists?
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The general answer is that += tries to call the __iadd__ special method, and if that isn't available it tries to use __add__ instead. So the issue is with the difference between these special methods.
The __iadd__ special method is for an in-place addition, that i...
Truncating all tables in a Postgres database
I regularly need to delete all the data from my PostgreSQL database before a rebuild. How would I do this directly in SQL?
...
When to use setAttribute vs .attribute= in JavaScript?
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This answer is not clear enough...I don't really feel I understand this yet.
– temporary_user_name
Oct 24 '13 at 21:48
1
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