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Remove duplicated rows using dplyr
...ce(from = 1, to = 1)
Or maybe a variation of unique() that would let you select which
variables to use:
df %>% unique(x, y)
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The type or namespace name 'Objects' does not exist in the namespace 'System.Data'
...ontext.tt and be nested under your edmx file in Solution Explorer. You can select the templates in Solution Explorer and press the Del key to delete them.
Note: In Web Site projects the templates will not be nested under your edmx file, but listed alongside it in Solution Explorer.
Note: In VB.N...
How to verify an XPath expression in Chrome Developers tool or Firefox's Firebug?
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In "Elements" panel, press Ctrl+F
In the search box, type in XPath or CSS Selector, if elements are found, they will be highlighted in yellow.
Firefox (since version 75)
Since FF 75 it's possible to use raw xpath query without evaluation xpath expressions, see documentation for more info.
Fir...
Limiting the number of records from mysqldump?
... @Phob: The --where option is basically appended to a query of the form SELECT * from table WHERE , so in this case you get SELECT * from table WHERE 1 limit 1000000. Without the 1, you would have an invalid query. Specifying 1 for a where clause (since 1 is always true) simply selects all reco...
Is there a way to get a collection of all the Models in your Rails app?
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EDIT: Just for fun, I found a way to list all classes
Module.constants.select { |c| (eval c).is_a? Class }
EDIT: Finally succeeded in listing all models without looking at directories
Module.constants.select do |constant_name|
constant = eval constant_name
if not constant.nil? and constan...
How to redirect to a 404 in Rails?
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Changed the selected answer to reflect the better practice. Thanks for the comments, guys!
– Yuval Karmi
Aug 14 '11 at 0:08
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How do I repeat an edit on multiple lines in Vim?
...al block by using
" allow the . to execute once for each line of a visual selection
vnoremap . :normal .<CR>
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Text editor to open big (giant, huge, large) text files [closed]
... for quick scripts, and its .. (range flip-flop) operator makes for a nice selection mechanism to limit the crud you have to wade through.
For example:
$ perl -n -e 'print if ( 1000000 .. 2000000)' humongo.txt | less
This will extract everything from line 1 million to line 2 million, and allow you ...
Android: allow portrait and landscape for tablets, but force portrait on phone?
...h their bools.xml files.
values-sw600dp
First of all, from the Project tab select the Project (rather than Android) filter in the navigator.
Then right click the app/src/main/res directory. Choose New > Android Resource Directory.
Select Smallest Screen Width, and then press the >> button....
What does the double colon (::) mean in CSS?
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It means pseudo element selector. It means the element to the right doesn't exist in the normal DOM, but can be selected.
A pseudo-element is made of two colons (::) followed by the name of the pseudo-element.
Source
It was originally only a ...