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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 ...
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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Find the max of two or more columns with pandas
...df = pd.DataFrame({"A": [1,2,3], "B": [-2, 8, 1]})
>>> df
A B
0 1 -2
1 2 8
2 3 1
>>> df[["A", "B"]]
A B
0 1 -2
1 2 8
2 3 1
>>> df[["A", "B"]].max(axis=1)
0 1
1 8
2 3
and so:
>>> df["C"] = df[["A", "B"]].max(axis=1)
>>> df
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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....
Scrolling a flexbox with overflowing content
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answered Feb 4 '14 at 0:59
Joseph SilberJoseph Silber
184k4747 gold badges324324 silver badges265265 bronze badges
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Why is isNaN(null) == false in JS?
...false.
So in the specific case x = null, null is converted to the number 0, (try evaluating Number(null) and see that it returns 0,) and isNaN(0) returns false. A string that is only digits can be converted to a number and isNaN also returns false. A string (e.g. 'abcd') that cannot be converted t...
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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What do the numbers in a version typically represent (i.e. v1.9.0.1)?
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200
In version 1.9.0.1:
1: Major revision (new UI, lots of new features, conceptual change, etc.)...
How to set Sqlite3 to be case insensitive when string comparing?
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10 Answers
10
Active
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Java regex capturing groups indexes
... e.g. (\.\w+)+, or to specify where alternation should take effect, e.g. ^(0*1|1*0)$ (^, then 0*1 or 1*0, then $) versus ^0*1|1*0$ (^0*1 or 1*0$).
A capturing group, apart from grouping, will also record the text matched by the pattern inside the capturing group (pattern). Using your example, (.*):...