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How to convert ActiveRecord results into an array of hashes

... as_json You should use as_json method which converts ActiveRecord objects to Ruby Hashes despite its name tasks_records = TaskStoreStatus.all tasks_records = tasks_records.as_json # You can now add new records and return the...
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How to export table as CSV with headings on Postgresql?

... COPY products_273 TO '/tmp/products_199.csv' WITH (FORMAT CSV, HEADER); as described in the manual. share | improve this answer ...
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How do I access command line arguments in Python?

...a small example: import argparse parser = argparse.ArgumentParser("simple_example") parser.add_argument("counter", help="An integer will be increased by 1 and printed.", type=int) args = parser.parse_args() print(args.counter + 1) and the output for python prog.py -h usage: simple_example [-h] ...
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Python date string to date object

...<stdin>", line 1, in <module> File "/usr/local/lib/python2.7/_strptime.py", line 308, in _strptime format_regex = _TimeRE_cache.compile(format) File "/usr/local/lib/python2.7/_strptime.py", line 265, in compile return re_compile(self.pattern(format), IGNORECASE) File "/usr/...
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Mathematical functions in Swift

...l math functions and constanst. A small snippet of the file ... func pow(_: CDouble, _: CDouble) -> CDouble func sqrtf(_: CFloat) -> CFloat func sqrt(_: CDouble) -> CDouble func erff(_: CFloat) -> CFloat ... var M_LN10: CDouble { get } /* loge(10) */ var M_PI: CDouble { get } /...
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What is the correct way to create a single-instance WPF application?

... NativeMethods.PostMessage( (IntPtr)NativeMethods.HWND_BROADCAST, NativeMethods.WM_SHOWME, IntPtr.Zero, IntPtr.Zero); } } } NativeMethods.cs // this class just wraps some Win32 stuff that we're going to use...
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clear javascript console in Google Chrome

... Chrome: console._commandLineAPI.clear(); Safari: console._inspectorCommandLineAPI.clear(); You can create your own variable, which works in both: if (typeof console._commandLineAPI !== 'undefined') { console.API = console._commandL...
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Read properties file outside JAR file

...main properties file is main.properties): ./ - the root of your program |__ main.jar |__ main.properties With this architecture, you can modify any property in the main.properties file using any text editor before or while your main.jar is running (depending on the current state of the program)...
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What is the use of static variable in C#? When to use it? Why can't I declare the static variable in

...red. Let me explain this with an example: class circle { public float _PI =3.14F; public int Radius; public funtionArea(int radius) { return this.radius * this._PI } } class program { public static void main() { Circle c1 = new Cirle(); flo...
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How can we generate getters and setters in Visual Studio?

..., you will have to have an instance variable for it: private PropertyType _property; public PropertyType PropertyName { get { //logic here return _property; } set { //logic here _property = value; } } Previous versions of Visual Studio al...