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Regular expression for floating point numbers

...g a floating point number is [+-]?([0-9]*[.])?[0-9]+ This will match: 123 123.456 .456 See a working example If you also want to match 123. (a period with no decimal part), then you'll need a slightly longer expression: [+-]?([0-9]+([.][0-9]*)?|[.][0-9]+) See pkeller's answer for a fuller...
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How to determine a Python variable's type?

... Use the type() builtin function: >>> i = 123 >>> type(i) <type 'int'> >>> type(i) is int True >>> i = 123.456 >>> type(i) <type 'float'> >>> type(i) is float True To check if a variable is of a given type, u...
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How to unset a JavaScript variable?

...hen the target isn't an object property. e.g., (function() { var foo = 123; delete foo; // wont do anything, foo is still 123 var bar = { foo: 123 }; delete bar.foo; // foo is gone }()); But since global variables are actually members of the window object, it works. When prototype c...
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Check if a String contains numbers Java

... } } return sb.toString(); } Examples: For input "123abc", the method above will return 123. For "abc1000def", 1000. For "555abc45", 555. For "abc", will return an empty string. share | ...
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Restore the state of std::cout after manipulating it

... { boost::io::ios_flags_saver ifs(x); x << std::hex << 123; } share | improve this answer | follow | ...
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REST URI convention - Singular or plural name of resource while creating it

...ll likely error, as this request doesn't make any sense, whereas /resource/123 makes perfect sense. Using /resource instead of /resources is similar to how you would do this if you were working with, say, a file system and a collection of files and /resource is the "directory" with the individual 1...
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How do I create multiple submit buttons for the same form in Rails?

... Similar solution to one suggested by @vss123 without using any gems: resources :plan do post :save, constraints: lambda {|req| req.params.key?(:propose)}, action: :propose post :save, constraints: lambda {|req| req.params.key?(:finalize)}, action: :finalize end...
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Convert string to integer type in Go?

... fmt.Printf("i=%d, type: %T\n", i, i) } Output (if called with argument "123"): i=123, type: int i=123, type: int64 i=123, type: int Parsing Custom strings There is also a handy fmt.Sscanf() which gives even greater flexibility as with the format string you can specify the number format (like ...
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How to print instances of a class using print()?

....it will act the following way in the Python shell: >>> t = Test(123, 456) >>> t <Test a:123 b:456> >>> print repr(t) <Test a:123 b:456> >>> print(t) From str method of Test: a is 123, b is 456 >>> print(str(t)) From str method of Test: a is ...
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How can I pass a list as a command-line argument with argparse?

...'<Required> Set flag', required=True) # Use like: # python arg.py -l 1234 2345 3456 4567 nargs='+' takes 1 or more arguments, nargs='*' takes zero or more. append parser.add_argument('-l','--list', action='append', help='<Required> Set flag', required=True) # Use like: # python arg.p...