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How do I calculate the normal vector of a line segment?
Suppose I have a line segment going from (x1,y1) to (x2,y2). How do I calculate the normal vector perpendicular to the line?
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How can I suppress column header output for a single SQL statement?
I'm executing some SQL statements in batch (using the mysql command-line binary). I want one of my several SELECT statements to not print the column headers, just the selected records. Is this possible?
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Best way to test if a generic type is a string? (C#)
I have a generic class that should allow any type, primitive or otherwise. The only problem with this is using default(T) . When you call default on a value type or a string, it initializes it to a reasonable value (such as empty string). When you call default(T) on an object, it returns null. Fo...
What's the 'environment' task in Rake?
According to " Custom Rake Tasks ":
3 Answers
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Can someone explain the HTML5 aria-* attribute?
I wanted to know what the aria-* attributes are used for. What values can they have, and are they defined values or can I create my own values?
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Join between tables in two different databases?
In MySQL, I have two different databases -- let's call them A and B .
4 Answers
4
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How to see if an NSString starts with a certain other string?
I am trying to check to see if a string that I am going to use as URL starts with http. The way I am trying to check right now doesn't seem to be working. Here is my code:
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Data structure for loaded dice?
Suppose that I have an n-sided loaded die where each side k has some probability p k of coming up when I roll it. I'm curious if there is good algorithm for storing this information statically (i.e. for a fixed set of probabilities) so that I can efficiently simulate a random roll of the die.
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Xcode - But… Where are our archives?
...ubmitted three versions of my app onto the App Store using the Build and Archive commands. But... Where are those archives?
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Change UICollectionViewCell size on different device orientations
I am using an UICollectionView with UICollectionViewFlowLayout .
6 Answers
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