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How to get first record in each group using Linq
...roup element by element.F1
into groups
select groups.OrderBy(p => p.F2).First();
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Select first 4 rows of a data.frame in R
How can I select the first 4 rows of a data.frame :
5 Answers
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How can I configure NetBeans to insert tabs instead of a bunch of spaces?
...it Tab for indenting code, I like to get a real tab. Meaning that when I select that, I only have one large thing selected. NetBeans inserts 5 spaces instead of a tab when I hit Tab . Is there a way I can change that?
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Correct way to add external jars (lib/*.jar) to an IntelliJ IDEA project
...ps for adding external jars in IntelliJ IDEA:
Click File from the toolbar
Select Project Structure option (CTRL + SHIFT + ALT + S on Windows/Linux, ⌘ + ; on Mac OS X)
Select Modules at the left panel
Select Dependencies tab
Select + icon
Select 1 JARs or directories option
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How to integrate CSS pre-processing within Eclipse? [closed]
...and then click OK.
Find the *.scss entry in the File Associations list and select it.
After selecting *.scss, on the bottom pane Associated editors:, click the Add... button.
Make sure Internal editors is selected on the top, then find and select CSS Editor and then click OK.
This associated the f...
How to get the max of two values in MySQL?
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Use GREATEST()
E.g.:
SELECT GREATEST(2,1);
Note: Whenever if any single value contains null at that time this function always returns null (Thanks to user @sanghavi7)
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Want to find records with no associated records in Rails
... get everyone with no friends in the first case:
Person.where('id NOT IN (SELECT DISTINCT(person_id) FROM friends)')
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How can I set the default value for an HTML element?
I thought that adding a "value" attribute set on the <select> element below would cause the <option> containing my provided "value" to be selected by default:
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Selecting with complex criteria from pandas.DataFrame
...se pandas it has some built in functions for comparison. So if you want to select values of "A" that are met by the conditions of "B" and "C" (assuming you want back a DataFrame pandas object)
df[['A']][df.B.gt(50) & df.C.ne(900)]
df[['A']] will give you back column A in DataFrame format.
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How can I set the value of a DropDownList using jQuery?
... have described above, yet the range validator keeps failing telling me to select a value (when the value selected is within range). Please see my question stackoverflow.com/questions/3165033/…
– James
Jul 7 '10 at 13:14
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