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Convert columns to string in Pandas
...taFrame([['A', 2], ['A', 4], ['B', 6]])
In [12]: df.to_json()
Out[12]: '{"0":{"0":"A","1":"A","2":"B"},"1":{"0":2,"1":4,"2":6}}'
In [13]: df[0].to_json()
Out[13]: '{"0":"A","1":"A","2":"B"}'
Note: you can pass in a buffer/file to save this to, along with some other options...
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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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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 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 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....
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, (.*):...
How to give border to any element using css without adding border-width to the whole width of elemen
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Anne
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answered Nov 29 '11 at 23:22
abensonabenson
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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 &&...
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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