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How do I get a substring of a string in Python?

...ieve this is by string slicing. MyString[a:b] gives you a substring from index a to (b - 1). share | improve this answer | follow | ...
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How to iterate for loop in reverse order in swift?

.... To iterate on a range in reverse order, they can be used as below: for index in stride(from: 5, to: 1, by: -1) { print(index) } //prints 5, 4, 3, 2 for index in stride(from: 5, through: 1, by: -1) { print(index) } //prints 5, 4, 3, 2, 1 Note that neither of those is a Range member fun...
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Convert seconds to Hour:Minute:Second

...e amount of days in the year starting with 0. You can obviously review the php date manual to cater to your specific needs. – Nightwolf Aug 11 '16 at 6:51  ...
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JavaScript equivalent to printf/String.Format

...s into an Array, whether it was originally or not, and the key will be the index (0, 1, 2...) of each array element coerced into a string (eg, "0", so "\\{0\\}" for your first regexp pattern). Neat. share | ...
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Selecting multiple columns in a pandas dataframe

..._ syntax (the []'s). df1 = df[['a', 'b']] Alternatively, if it matters to index them numerically and not by their name (say your code should automatically do this without knowing the names of the first two columns) then you can do this instead: df1 = df.iloc[:, 0:2] # Remember that Python does not ...
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Declare and initialize a Dictionary in Typescript

... which exact TS version). I get these errors in VS, as you would expect: Index signatures are incompatible. Type '{ firstName: string; }' is not assignable to type 'IPerson'. Property 'lastName' is missing in type '{ firstName: string; }'. Apparently this doesn't work when passing the ini...
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What does enumerate() mean?

...rt, it loops over the elements of an iterable (like a list), as well as an index number, combined in a tuple: for item in enumerate(["a", "b", "c"]): print item prints (0, "a") (1, "b") (2, "c") It's helpful if you want to loop over a sequence (or other iterable thing), and also want to ha...
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How to make good reproducible pandas examples

...]: B A 1 5 4 6 But say what's incorrect: the A column is in the index rather than a column. do show you've done some research (search the docs, search StackOverflow), give a summary: The docstring for sum simply states "Compute sum of group values" The groupby docs don't give any...
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C++ sorting and keeping track of indexes

...ce of samples in ascending order, but I also want to remember the original indexes of the new samples. 15 Answers ...
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How to make rounded percentages add up to 100%

...equence = original .Zip(Enumerable.Range(0, int.MaxValue), (x, index) => new { x, index }) .OrderBy(a => original[a.index] - rounded[a.index]) .ThenByDescending(a => a.index) .Select(a => a.index).ToList(); } else { appl...