大约有 42,000 项符合查询结果(耗时:0.0615秒) [XML]

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Pandas aggregate count distinct

... How about either of: >>> df date duration user_id 0 2013-04-01 30 0001 1 2013-04-01 15 0001 2 2013-04-01 20 0002 3 2013-04-02 15 0002 4 2013-04-02 30 0002 >>> df.groupby("date").agg({"duration": np.sum, "user...
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Calling a Fragment method from a parent Activity

I see in the Android Fragments Dev Guide that an "activity can call methods in a fragment by acquiring a reference to the Fragment from FragmentManager, using findFragmentById() or findFragmentByTag() ." ...
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How do I use Linq to obtain a unique list of properties from a list of objects?

I'm trying to use Linq to return a list of ids given a list of objects where the id is a property. I'd like to be able to do this without looping through each object and pulling out the unique ids that I find. ...
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Remove vertical padding from horizontal ProgressBar

... I use the following as a workaround for this issue. android:layout_marginBottom="-8dp" android:layout_marginTop="-4dp" share | improve this answer | follow...
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android.content.res.Resources$NotFoundException: String resource ID #0x0

I'm developing an Android app which reads data from MySQL database and I faced this error. I have this XML layout: 7 Answer...
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Update a table using JOIN in SQL Server?

...umn to the aggregate of another column (which violates the principle of avoiding storing redundant data), you can use a CTE (common table expression) - see here and here for more details: ;WITH t2 AS ( SELECT [key], CalculatedColumn = SUM(some_column) FROM dbo.table2 GROUP BY [key] ) UPDA...
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How to set selected value of jquery select2?

... To dynamically set the "selected" value of a Select2 component: $('#inputID').select2('data', {id: 100, a_key: 'Lorem Ipsum'}); Where the second parameter is an object with expected values. UPDATE: This does work, just wanted to note that in the new select2, "a_key" is "text" in a standard sel...
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Add a column to existing table and uniquely number them on MS SQL Server

... this could be achieved as follows: alter table Example add NewColumn int identity(1,1) share | improve this answer | follow | ...
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Check if checkbox is checked with jQuery

How can I check if a checkbox in a checkbox array is checked using the id of the checkbox array? 23 Answers ...
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How do you perform a left outer join using linq extension methods

... For a (left outer) join of a table Bar with a table Foo on Foo.Foo_Id = Bar.Foo_Id in lambda notation: var qry = Foo.GroupJoin( Bar, foo => foo.Foo_Id, bar => bar.Foo_Id, (x,y) => new { Foo = x, Bars = y }) .SelectMany( x =...