Storing acceleration values in Objective-C/Cocoa?

Posted by ASchlaep on Stack Overflow See other posts from Stack Overflow or by ASchlaep
Published on 2010-05-09T20:05:19Z Indexed on 2010/05/09 20:08 UTC
Read the original article Hit count: 133

Filed under:

iphone

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objective-c

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accelerometer

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nsmutablearray

Hi all,

I'm writing for the iPhone and I'm trying to measure the time between maximum accelerations. Imagine you've attached your iPhone to an oscillating spring. What I want to do is measure the frequency of the oscillation. The way I am going about doing this is storing a certain number acceleration values (updated 20 times per second) in an NSMutableArray and comparing the current acceleration value with previous acceleration values.

How do I add each updated acceleration value to the NSMutableArray and at the same time delete values from the back of the array as I don't need them any more?

Thanks in advance!

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