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dplyr: “Error in n(): function should not be called directly”

...ction" specification, like example below: delay <- dplyr::summarise(by_tailnum, count = n(), dist = mean(distance, na.rm = TRUE), delay = mean(arr_delay, na.rm = TRUE)) share | improv...
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Disable a Button

... I also get an error if I change (_ sender: ) to UIButton . The error reads: Value of type '(UIButton) -> ()' has no member 'isEnabled' – user9470831 Feb 5 '19 at 4:25 ...
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Change private static final field using Java reflection

...ic #2; //Field java/lang/System.out:Ljava/io/PrintStream; 3: iconst_1 4: invokevirtual #3; //Method java/io/PrintStream.println:(Z)V 7: return share | improve this answer | ...
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Git push rejected after feature branch rebase

...t to use the following sequence: git rebase master git checkout -b feature_branch_2 git push origin feature_branch_2 Yeah, new branch, this should solve this without a --force, which I think generally is a major git drawback. ...
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System.IO.Packaging

...indows 10 maybe you could found here C:\Windows\Microsoft.NET\assembly\GAC_MSIL\WindowsBase\v4.0_4.0.0.0__31bf3856ad364e35\ share | improve this answer | follow ...
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usr/bin/ld: cannot find -l

...ame across another post on the Internets that suggested to run make with LD_DEBUG=all: LD_DEBUG=all make Although I got a TON of debugging output, it wasn't actually helpful. It added more confusion than anything else. So, I was about to give up. Then, I had an epiphany. I thought to actually...
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Null coalescing in powershell

...ms -ne $null [string]::Join(', ', ($instances | ForEach-Object -Process { $_.GetType() })) # Result: System.String, System.Int32, System.Int32, System.String, System.Object[], System.Boolean, System.Boolean -eq works similarly, which is useful for counting null entries: ($null, 'a', $null -eq $n...
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Determine if Python is running inside virtualenv

...t reliable way to check for this is to check whether sys.prefix == sys.base_prefix. If they are equal, you are not in a virtual environment; if they are unequal, you are. Inside a virtual environment, sys.prefix points to the virtual environment, and sys.base_prefix is the prefix of the system Pytho...
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Get the Last Inserted Id Using Laravel Eloquent

... used like this. return Response::json(array('success' => true, 'last_insert_id' => $data->id), 200); For updated laravel version try this return response()->json(array('success' => true, 'last_insert_id' => $data->id), 200); ...
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How can I group data with an Angular filter?

...ddle.net/TD7t3/ The filter app.filter('groupBy', function() { return _.memoize(function(items, field) { return _.groupBy(items, field); } ); }); Note the 'memoize' call. This underscore method caches the result of the function and stops angular from evaluating the fil...