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Rails DB Migration - How To Drop a Table?
...ation to already have the code you want. You can create an empty migration and then populate it with the code you need.
You can find information about how to accomplish different tasks in a migration here:
http://api.rubyonrails.org/classes/ActiveRecord/Migration.html
More specifically, you can s...
Jar Mismatch Found 2 versions of android-support-v4.jar in the dependency list
I am trying to create 2 versions of an Android app (free/paid). I have an Android Library that contains files common to both. I created a new Android project and am trying to use the Library but get the error below:
...
What's the role of GetHashCode in the IEqualityComparer in .NET?
I'm trying to understand the role of the GetHashCode method of the interface IEqualityComparer.
3 Answers
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Two inline-block, width 50% elements wrap to second line [duplicate]
I would like to have two columns of 50% width space, and avoid floats.
So i thought using display:inline-block .
5 Answers...
Standard deviation of a list
I want to find mean and standard deviation of 1st, 2nd,... digits of several (Z) lists. For example, I have
8 Answers
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How to change Navigation Bar color in iOS 7?
... you set the translucent property to NO.
Availability
Available in iOS 7.0 and later.
Declared In
UINavigationBar.h
Code
NSArray *ver = [[UIDevice currentDevice].systemVersion componentsSeparatedByString:@"."];
if ([[ver objectAtIndex:0] intValue] >= 7) {
// iOS 7.0 or later
self.navig...
How do I bind to list of checkbox values with AngularJS?
...ither use a simple array or an array of objects. Each solution has it pros and cons. Below you'll find one for each case.
With a simple array as input data
The HTML could look like:
<label ng-repeat="fruitName in fruits">
<input
type="checkbox"
name="selectedFruits[]"
val...
Reading an Excel file in PHP [closed]
...Excel file (Office 2003). There is an Excel file that needs to be uploaded and its contents parsed.
8 Answers
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Error when changing to master branch: my local changes would be overwritten by checkout
...
Your error appears when you have modified a file and the branch that you are switching to has changes for this file too (from latest merge point).
Your options, as I see it, are - commit, and then amend this commit with extra changes (you can modify commits in git, as long...
Where does Scala look for implicits?
...bout the latter type, if one calls a method m on an object o of a class C, and that class does not support method m, then Scala will look for an implicit conversion from C to something that does support m. A simple example would be the method map on String:
"abc".map(_.toInt)
String does not supp...