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Laravel Eloquent Sum of relation's column
...The documentation is a little light for some of the Collection methods but all the query builder aggregates are seemingly available besides avg() that can be found at http://laravel.com/docs/queries#aggregates.
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Func delegate with no return type
All of the Func delegates return a value. What are the .NET delegates that can be used with methods that return void?
7 Ans...
How to drop rows of Pandas DataFrame whose value in a certain column is NaN
...ta, including dropna(), is built into pandas explicitly. Aside from potentially improved performance over doing it manually, these functions also come with a variety of options which may be useful.
In [24]: df = pd.DataFrame(np.random.randn(10,3))
In [25]: df.iloc[::2,0] = np.nan; df.iloc[::4,1] ...
Codesign error: Certificate identity appearing twice
...same problem.
It has been fixed.
It came after I submitted an app and installed a few certificates to sign the app.
Quick Fix:
Open up KEYCHAIN ACCESS > click on MY CERTIFICATES> in there you will probably see
iPhone Developer: . You will probably see it TWICE!
Select the one with the earl...
What's the best way to put a c-struct in an NSArray?
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@Joe Blow @Catfish_Man It actually copies the structure p, not a pointer to it. The @encode directive provides all the information necessary about how big the structure is. When you release the NSValue (or when the array does), its copy of the structure i...
Favorite Visual Studio keyboard shortcuts [closed]
...fancy tool panel. Instead, it's just about letting me see the code.
With all the panels surrounding you, the area you use to actually write code becomes too small.
In this cases, Shift+Alt+Enter comes in to the rescue and gets the code window in focus in full screen mode. Hit it again, and you h...
Using -performSelector: vs. just calling the method
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Basically performSelector allows you to dynamically determine which selector to call a selector on the given object. In other words the selector need not be determined before runtime.
Thus even though these are equivalent:
[a...
How do I clone a subdirectory only of a Git repository?
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EDIT: As of Git 2.19, this is finally possible, as can be seen in this answer.
Consider upvoting that answer.
Note: in Git 2.19, only client-side support is implemented, server-side support is still missing, so it only works when cloning local repositories...
How to remove RVM (Ruby Version Manager) from my system
... that will pull it:
rvm implode
This will remove the rvm/ directory and all the rubies built within it. In order to remove the final trace of rvm, you need to remove the rvm gem, too:
gem uninstall rvm
If you've made modifications to your PATH you might want to pull those, too. Check your .bas...
Can unit testing be successfully added into an existing production project? If so, how and is it wor
...oject that is in production. It was started 18 months ago before I could really see any benefit of TDD (face palm) , so now it's a rather large solution with a number of projects and I haven't the foggiest idea where to start in adding unit tests. What's making me consider this is that occasionally...