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How do I replace NA values with zeros in an R dataframe?

...u post it and not worked. Because this I posted the question. But I tried know and worked perfectly. I think I was doing something wrong. – Renato Dinhani Nov 17 '11 at 14:08 12 ...
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How do I filter query objects by date range in Django?

... What's date1's datatype? I've got datetime object now. – user469652 Jan 12 '11 at 12:25 8 ...
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Checking to see if a DateTime variable has had a value assigned

...est.StartDateTime == default(DateTime) { request.StartDateTime = DateTime.Now; } – Menol May 13 '16 at 8:33 ...
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bash/fish command to print absolute path to a file

...will still give you a valid path given some relative path. If you want to know about file existence use another tool like e.g. test. – Benjamin Bannier Feb 27 '13 at 17:47 ...
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How can I get a list of locally installed Python modules?

... Now, these methods I tried myself, and I got exactly what was advertised: All the modules. Alas, really you don't care much about the stdlib, you know what you get with a python install. Really, I want the stuff that I i...
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How to check for valid email address? [duplicate]

...g it even a little tighter. Seems safe to limit TLD to alphanumeric right now (still haven't seen a TLD that has non-ASCII chars). Using this now: re.compile(r"[^@\s]+@[^@\s]+\.[a-zA-Z0-9]+$") – gaefan Aug 29 '15 at 15:39 ...
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How to write DataFrame to postgres table?

...s 0.14 (released end of May 2014), postgresql is supported. The sql module now uses sqlalchemy to support different database flavors. You can pass a sqlalchemy engine for a postgresql database (see docs). E.g.: from sqlalchemy import create_engine engine = create_engine('postgresql://scott:tiger@lo...
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How to find where gem files are installed

... After installing the gems, if you want to know where a particular gem is. Try typing: gem list You will be able to see the list of gems you have installed. Now use bundle show and name the gem you want to know the path for, like this: bundle show <gemName&g...
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Creating functions in a loop

... how do you know how to fix these things? – alwbtc Aug 18 '18 at 15:49 3 ...
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Apply multiple functions to multiple groupby columns

... 0.687672 1.754877 0.672401 Using apply and returning a Series Now, if you had multiple columns that needed to interact together then you cannot use agg, which implicitly passes a Series to the aggregating function. When using apply the entire group as a DataFrame gets passed into the fu...