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Why is a pure virtual function initialized by 0?
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The reason =0 is used is that Bjarne Stroustrup didn't think he could get another keyword, such as "pure" past the C++ community at the time the feature was being implemented. This is described in his book, The Design & Evolution of ...
How to convert a Binary String to a base 10 integer in Java
...ithout leading zeroes) that I want to convert to their corresponding base 10 numbers. Consider:
9 Answers
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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 to get the seconds since epoch from the time + date output of gmtime()?
...calendar.timegm().
>>> calendar.timegm(time.gmtime())
1293581619.0
You can turn your string into a time tuple with time.strptime(), which returns a time tuple that you can pass to calendar.timegm():
>>> import calendar
>>> import time
>>> calendar.timegm(time....
How to get the first and last date of the current year?
Using SQL Server 2000, how can I get the first and last date of the current year?
18 Answers
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How to use hex color values
...f, green ff and blue ff. You can write hexadecimal notation in Swift using 0x prefix, e.g 0xFF
To simplify the conversion, let's create an initializer that takes integer (0 - 255) values:
extension UIColor {
convenience init(red: Int, green: Int, blue: Int) {
assert(red >= 0 &&...
Changing iframe src with Javascript
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answered Sep 16 '10 at 19:43
PekkaPekka
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RegEx - Match Numbers of Variable Length
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{[0-9]+:[0-9]+}
try adding plus(es)
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Pandas dataframe get first row of each group
...column:
>>> df.groupby('id').first().reset_index()
id value
0 1 first
1 2 first
2 3 first
3 4 second
4 5 first
5 6 first
6 7 fourth
To get n first records, you can use head():
>>> df.groupby('id').head(2).reset_index(drop=True)
id value
0 ...
Ignore with CSS?
...'t answer the question exactly as stated, but it does achieve the goal in all modern browsers.
– Andrew Lundin
Jul 25 '14 at 20:05
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