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Why does this iterative list-growing code give IndexError: list assignment index out of range?
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j is an empty list, but you're attempting to write to element [0] in the first iteration, which doesn't exist yet.
Try the following instead, to add a new element to the end of the list:
for l in i:
j.append(l)
Of course, you'd never do this in practice if all you wanted to do wa...
MySQL, better to insert NULL or empty string?
...re differences:
A LENGTH of NULL is NULL, a LENGTH of an empty string is 0.
NULLs are sorted before the empty strings.
COUNT(message) will count empty strings but not NULLs
You can search for an empty string using a bound variable but not for a NULL. This query:
SELECT *
FROM mytable
WHERE ...
How do I look inside a Python object?
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360
Python has a strong set of introspection features.
Take a look at the following built-in funct...
JavaScript - Getting HTML form values
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answered Aug 23 '10 at 11:28
user406632user406632
1,28311 gold badge1010 silver badges88 bronze badges
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Convert PHP closing tag into comment
... you.
– v1n_vampire
Mar 5 '13 at 9:30
1
I had to use this trick in C 2 days ago for a string cont...
Swift days between two NSDates
...onsider the time difference as well. For example if you compare the dates 2015-01-01 10:00 and 2015-01-02 09:00, days between those dates will return as 0 (zero) since the difference between those dates is less than 24 hours (it's 23 hours).
If your purpose is to get the exact day number between tw...
How to remove non-alphanumeric characters?
I need to remove all characters from a string which aren't in a-z A-Z 0-9 set or are not spaces.
9 Answers
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split string only on first instance of specified character
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answered Jan 5 '11 at 18:30
MarkMark
30.8k1111 gold badges3838 silver badges4444 bronze badges
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Usage of __slots__?
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1083
In Python, what is the purpose of __slots__ and what are the cases one should avoid this?
TL...
Getting all types that implement an interface
... reflection, how can I get all types that implement an interface with C# 3.0/.NET 3.5 with the least code, and minimizing iterations?
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