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Aggregate / summarize multiple variables per group (e.g. sum, mean)
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what if I instead of x1 and x2 I want to use all the remaining variables (other than year, month)
– Clock Slave
Mar 16 '16 at 11:22
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Why is the Android test runner reporting “Empty test suite”?
...odules ("Projects" in Eclipse). The Unit test module has its own AndroidManifest.xml, which I have pasted at the bottom. I am trying to run an ActivityUnitTestCase , since the tests will be dependent upon the Context -object.
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iOS - How to set a UISwitch programmatically
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If you are using a UISwitch, then as seen in the developer API, the task setOn: animated: should do the trick.
- (void)setOn:(BOOL)on animated:(BOOL)animated
So to set the switch ON in your program, you would use:
Objecti...
LINQ Distinct operator, ignore case?
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[See Marc Gravells answer if you want the most concise approach]
After some investigation and good feedback from Bradley Grainger I've implemented the following IEqualityComparer. It suports a case insensitive Distinct() statement (just pass an inst...
What tools are there for functional programming in C?
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Sadly, this doesn’t work in practice: if you want the closure to capture anything, it requires an executable stack, which is a terrible security practice. Personally, I don’t think it is useful at all.
– Demi
Aug 2 '17 at...
Execution time of C program
... 60ms.
clock() is standard C; it works "everywhere". There are system-specific functions, such as getrusage() on Unix-like systems.
Java's System.currentTimeMillis() does not measure the same thing. It is a "wall clock": it can help you measure how much time it took for the program to execute, but...
No Persistence provider for EntityManager named
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I am using Derby and it wasn't necessary to specify this (I did, but then removed it once I solved the problem, just to make sure). I was getting the error finally because persistence.xml was not in the src/META-INF folder, even though it had been in a folder in the Eclips...
How to query MongoDB with “like”?
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Actually, it depends. If the query doesn't use an index, and must do a table scan, then it can certainly be expensive. If you're doing a 'starts with' regex query, then that can use an index. Best to run an explain() to see what's happening.
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Groovy / grails how to determine a data type?
...ss()
You can abbreviate this to someObject.class in most cases. However, if you use this on a Map it will try to retrieve the value with key 'class'. Because of this, I always use getClass() even though it's a little longer.
If you want to check if an object implements a particular interface or e...
Is it possible to set async:false to $.getJSON call
...before your json ajax call. And you can set it to true after call retuns ( if there are other usages of ajax on page if you want them async )
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