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Equivalent of “throw” in R
...does one "throw" an error in R? I have a function that takes a data frame and some column names and does stuff with them. If the columns don't exist, I want the function to stop and to stop all functions depending on it.
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Entity Framework - Invalid Column Name '*_ID"
I've narrowed this down to some issue between Code First and Database first EF, but I'm not sure how to fix it. I'll try to be as clear as I can, but I honestly am missing some of the understanding here myself. This is Entity Framework 4.4
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Facebook App: localhost no longer works as app domain
I've been writing a game for Facebook using Rails and jQuery. Since I started using the Facebook Javascript SDK, using localhost as an app domain seemed to work just fine. I was able to test my game both locally and on Heroku.
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Set up DNS based URL forwarding in Amazon Route53 [closed]
...eeded to find a solution that did not require anything other than Route 53 and S3. I created a how-to guide for my blog detailing what I did.
Here is what I came up with.
Objective
Using only the tools available in Amazon S3 and Amazon Route 53, create a URL Redirect that automatically for...
What's the best Django search app? [closed]
I'm building a Django project that needs search functionality, and until there's a django.contrib.search , I have to choose a search app. So, which is the best? By "best" I mean...
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How do SQL EXISTS statements work?
I'm trying to learn SQL and am having a hard time understanding EXISTS statements. I came across this quote about "exists" and don't understand something:
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How to store int[] array in application Settings
... C# express 2008. I'm an experienced C++ developer, but I am pretty much brand new to C# and .NET.
8 Answers
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iOS: Multi-line UILabel in Auto Layout
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Use -setPreferredMaxLayoutWidth on the UILabel and autolayout should handle the rest.
[label setPreferredMaxLayoutWidth:200.0];
See the UILabel documentation on preferredMaxLayoutWidth.
Update:
Only need to set the height constraint in storyboard to Greater than or e...
How to put multiple statements in one line?
...t is not possible with Python (which makes Python close to useless for command-line one-liner programs). Even explicit use of parentheses does not avoid the syntax exception. You can get away with a sequence of simple statements, separated by semi-colon:
for i in range(10): print "foo"; print "bar"...
When to use in vs ref vs out
...use the parameter keyword out instead of ref . While I (I think) understand the difference between the ref and out keywords (that has been asked before ) and the best explanation seems to be that ref == in and out , what are some (hypothetical or code) examples where I should always use...