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What's the difference between lists enclosed by square brackets and parentheses in Python?
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Square brackets are lists while parentheses are tuples.
A list is mutable, meaning you can change its contents:
>>> x = [1,2]
>>> x.append(3)
>>> x
[1, 2, 3]
while tuples are not:
>>> x ...
Why can't I center with margin: 0 auto?
I have a #header div that is 100% width and within that div I have an unordered list. I have applied margin: 0 auto to the unordered list but it won't center it within the header div.
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How do I calculate the normal vector of a line segment?
Suppose I have a line segment going from (x1,y1) to (x2,y2). How do I calculate the normal vector perpendicular to the line?
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sqlalchemy flush() and get inserted id?
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Your sample code should have worked as it is. SQLAlchemy should be providing a value for f.id, assuming its an autogenerating primary-key column. Primary-key attributes are populated immediately within the flush() process as t...
What does “%.*s” mean in printf?
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You can use an asterisk (*) to pass the width specifier/precision to printf(), rather than hard coding it into the format string, i.e.
void f(const char *str, int str_len)
{
printf("%.*s\n", str_len, str);
}
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What is the purpose of the -nodes argument in openssl?
What is the purpose of the -nodes argument in openssl?
2 Answers
2
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Rails where condition using NOT NIL
Using the rails 3 style how would I write the opposite of:
5 Answers
5
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Setting href attribute at runtime
What is the best way to set the href attribute of the <a> tag at run time using jQuery?
5 Answers
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Filtering a list based on a list of booleans
I have a list of values which I need to filter given the values in a list of booleans:
6 Answers
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Comments in command-line Zsh
I switched quite recently from Bash to Zsh on Ubuntu and I'm quite happy about it. However, there is something I really miss and I did not find how to achieve the same thing.
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