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How to get the index of an item in a list in a single step?

...g different (e.g. on top of any IEnumerable<>). Use the overload of Select which takes an index in the predicate, so you transform your list into an (index, value) pair: var pair = myList.Select((Value, Index) => new { Value, Index }) .Single(p => p.Value.Prop == oProp...
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How to redirect and append both stdout and stderr to a file with Bash?

... cmd >>file.txt 2>&1 Bash executes the redirects from left to right as follows: >>file.txt: Open file.txt in append mode and redirect stdout there. 2>&1: Redirect stderr to "where stdout is currently going". In this case, that is a file opened in append mode....
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Data structure: insert, remove, contains, get random element, all at O(1)

...o other solutions). The requirement that's tricky is the "random element" selection: in a hash table, you would need to scan or probe for such an element. For closed hashing / open addressing, the chance of any given bucket being occupied is size() / capacity(), but crucially this is typically kep...
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Selecting multiple classes with jQuery

I’ve had a good look and can’t seem to find out how to select all elements matching certain classes in one jQuery selector statement such as this: ...
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How do I specify a password to 'psql' non-interactively?

...ORD="$(pbpaste)" --rm postgres psql -h www.example.com dbname username -c 'SELECT * FROM table;' – Bilal Akil Nov 23 '17 at 4:34 3 ...
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Aggregate function in an SQL update query?

... UPDATE t1 SET t1.field1 = t2.field2Sum FROM table1 t1 INNER JOIN (select field3, sum(field2) as field2Sum from table2 group by field3) as t2 on t2.field3 = t1.field3 share | improve...
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How to get a group of toggle buttons to act like radio buttons in WPF?

...ike toggle buttons, but also as radio buttons where only one button can be selected / pressed down at a current time. It also need to have a state where none of the buttons are selected / pressed down. ...
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How to map calculated properties with JPA and Hibernate

...e float finalPrice; Or even complex queries on other tables: @Formula("(select min(o.creation_date) from Orders o where o.customer_id = id)") private Date firstOrderDate; Where id is the id of the current entity. The following blog post is worth the read: Hibernate Derived Properties - Perform...
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How to join int[] to a character separated string in .NET?

... var ints = new int[] {1, 2, 3, 4, 5}; var result = string.Join(",", ints.Select(x => x.ToString()).ToArray()); Console.WriteLine(result); // prints "1,2,3,4,5" EDIT: As of (at least) .NET 4.5, var result = string.Join(",", ints.Select(x => x.ToString()).ToArray()); is equivalent to: v...
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ComboBox: Adding Text and Value to an Item (no Binding Source)

...ext1"; item.Value = 12; comboBox1.Items.Add(item); comboBox1.SelectedIndex = 0; MessageBox.Show((comboBox1.SelectedItem as ComboboxItem).Value.ToString()); } share | improve this...