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Filtering for empty or NULL names in a queryset
...e.objects.exclude(alias__isnull=True)
If you need to exclude null values and empty strings, the preferred way to do so is to chain together the conditions like so:
Name.objects.exclude(alias__isnull=True).exclude(alias__exact='')
Chaining these methods together basically checks each condition i...
Which terminal command to get just IP address and nothing else?
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It says that -i and -I are both illegal options
– Mason
Dec 16 '11 at 3:08
3
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Update built-in vim on Mac OS X
...his line to your .bashrc or .profile:
alias vim='/path/to/your/own/vim'
and/or change your $PATH so that it looks into its location before the default location.
The best thing to do, in my opinion, is to simply download the latest MacVim which comes with a very complete vim executable and use it...
Does using “new” on a struct allocate it on the heap or stack?
...ut where value type variables are allocated. That's a different question - and one to which the answer isn't just "on the stack". It's more complicated than that (and made even more complicated by C# 2). I have an article on the topic and will expand on it if requested, but let's deal with just the ...
When should I release objects in -(void)viewDidUnload rather than in -dealloc?
...ontroller means that even when its view is removed from the view hierarchy and released to save memory, through which the subviews are also released by the view, they will not actually be deallocated because the UIViewController itself still contains its own outstanding retaining references to those...
How can I improve my paw detection?
...ghtly more work.
The two animations below show your "Overlapping Paws" and "Grouped Paws" example data. This method seems to be working perfectly. (And for whatever it's worth, this runs much more smoothly than the GIF images below on my machine, so the paw detection algorithm is fairly fast......
Is there an eval() function in Java? [duplicate]
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You can use the ScriptEngine class and evaluate it as a Javascript string.
ScriptEngineManager manager = new ScriptEngineManager();
ScriptEngine engine = manager.getEngineByName("js");
Object result = engine.eval("4*5");
There may be a better way, but this ...
How do I unload (reload) a Python module?
I have a long-running Python server and would like to be able to upgrade a service without restarting the server. What's the best way do do this?
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How to check for an undefined or null variable in JavaScript?
...xistingObj.someUndefProperty. An undefined property doesn't yield an error and simply returns undefined, which, when converted to a boolean, evaluates to false. So, if you don't care about
0 and false, using if(obj.undefProp) is ok. There's a common idiom based on this fact:
value = obj.prop || de...
Android: How to stretch an image to the screen width while maintaining aspect ratio?
...to download an image (of unknown size, but which is always roughly square) and display it so that it fills the screen horizontally, and stretches vertically to maintain the aspect ratio of the image, on any screen size. Here is my (non-working) code. It stretches the image horizontally, but not vert...