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How can I find the number of days between two Date objects in Ruby?

...conds, such as this example 2.0.0-p195 :017 > a_date_time = DateTime.now => #<DateTime: 2013-12-31T12:23:03-08:00 ((2456658j,73383s,725757000n),-28800s,2299161j)> 2.0.0-p195 :018 > b_date_time = DateTime.now-20 => #<DateTime: 2013-12-11T12:23:06-08:00 ((2456638j,73386s,699...
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'Must Override a Superclass Method' Errors after importing a project into Eclipse

...-> Preferences menu item, then select Java and Compiler in the dialog. Now it still may show compiler compliance level at 1.6, yet you still see this problem. So now select the link "Configure Project Specific Settings..." and in there you'll see the project is set to 1.5, now change this to 1....
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Can't install PIL after Mac OS X 10.9

... tool, in Mountain Lion this was an option on the xcode Download page, but now you have to register with your apple id and download from: https://developer.apple.com/downloads/ Look for Command Line Tools (OS X Mavericks) for Xcode 2) Install everything needed for python (using brew), I believe yo...
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Class method differences in Python: bound, unbound and static

...f a class, cf. this question) to not create bound methods for method_two. Now, you can invoke static method both on an instance or on the class directly: >>> a_test = Test() >>> a_test.method_one() Called method_one >>> a_test.method_two() Called method_two >>> ...
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Summarizing multiple columns with dplyr? [duplicate]

...x. I have a data frame with different variables and one grouping variable. Now I want to calculate the mean for each column within each group, using dplyr in R. ...
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How to create .ipa file using Xcode?

...validate your archive by pressing Validate (optional step but recommended) Now press on Export button This will open list of method for export. Select the export method as per your requirement and click on Next button. This will show list of team for provisioning. Select accordingly and p...
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How are parameters sent in an HTTP POST request?

...are what it looks like, so I won't show an example, but it can be good to know that it exists. share | improve this answer | follow | ...
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How to properly match varargs in Mockito

... for info anyVararg is now deprecated: "@deprecated as of 2.1.0 use any()" – alexbt Nov 13 '16 at 20:12 ...
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What are the differences between JSON and JSONP?

... This is usually used to allow for cross-site AJAX with JSON data. If you know that example.com is serving JSON files that look like the JSONP example given above, then you can use code like this to retrieve it, even if you are not on the example.com domain: function func(json){ alert(json.name);...
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MySQL SELECT only not null values

...uld use IS NOT NULL. (The comparison operators = and <> both give UNKNOWN with NULL on either side of the expression.) SELECT * FROM table WHERE YourColumn IS NOT NULL; Just for completeness I'll mention that in MySQL you can also negate the null safe equality operator but this is not sta...