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Extract a substring according to a pattern

... sub to replace it with a colon first. For example, if the separator were _ then string <- sub("_", ":", string) c(read.dcf(textConnection(string))) ## [1] "E001" "E002" "E003" 7) separate 7a) Using tidyr::separate we create a data frame with two columns, one for the part before the colon and o...
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C#: Assign same value to multiple variables in single statement

...ssorTest { public AccessorTest(int value = default(int)) { _Value = value; } private int _Value; public int Value { get { Console.WriteLine("AccessorTest.Value.get {0}", _Value); return _Value; } set { ...
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How to parse float with two decimal places in javascript?

I have the following code. I would like to have it such that if price_result equals an integer, let's say 10, then I would like to add two decimal places. So 10 would be 10.00. Or if it equals 10.6 would be 10.60. Not sure how to do this. ...
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How to do an instanceof check with Scala(Test)

... tiger shouldBe a [Tiger] is the current syntax scalatest.org/at_a_glance/FlatSpec – jhegedus May 16 '17 at 4:06 2 ...
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Apply multiple functions to multiple groupby columns

...ame, you can use a normal function and supply a custom name to the special __name__ attribute like this: def max_min(x): return x.max() - x.min() max_min.__name__ = 'Max minus Min' df.groupby('group').agg({'a':['sum', 'max'], 'b':'mean', 'c'...
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How can I pass parameters to a partial view in mvc 4

... If you just render a partial with just the partial name: @Html.Partial("_SomePartial") It will actually pass your model as an implicit parameter, the same as if you were to call: @Html.Partial("_SomePartial", Model) Now, in order for your partial to actually be able to use this, though, it t...
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What are deferred objects?

...e".split(" "), // Create a simple deferred (one callbacks list) /* Class: _Deferred. * methods: done, resolve, resolveWith, isResolved * internal method: cancel * * Basically allows you to attach callbacks with the done method. * Then resolve the deferred action whenever you want with an a...
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How to compile and run C/C++ in a Unix console/Mac terminal?

...pp -o main.out", and get this error, Undefined symbols for architecture x86_64: "std::__1::locale::use_facet(std::__1::locale::id&) const", ... turns out the reason is, gcc default-links is libc. while using g++ will link with libstdc++. So use "g++ main.cpp -o main.out" may be better. ...
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Unique Key constraints for multiple columns in Entity Framework

... With Entity Framework 6.1, you can now do this: [Index("IX_FirstAndSecond", 1, IsUnique = true)] public int FirstColumn { get; set; } [Index("IX_FirstAndSecond", 2, IsUnique = true)] public int SecondColumn { get; set; } The second parameter in the attribute is where you can spec...
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Is Big O(logn) log base e?

... But it's very easy to show that log_2 n is in Θ(log_a n) for any base a, so I'm not sure I see how using base 2 is "more correct". – bcat Oct 15 '09 at 0:34 ...