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Can't figure out error  RSS feed

 
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Here is the code



I get the error Cannot read property 0 of undefined. What does this mean and how can I fix it?
 
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What is the purpose of line 12? Appending a string to an array? Does that make sense?

I'd advise breaking this down into multiple functions that each perform one duty.
 
Rocky Rocha
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tmpArr is an array. I'm making an x*x array.
 
Bear Bibeault
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Bear Bibeault wrote:Appending a string to an array? Does that make sense?

 
Rocky Rocha
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Okay, so I figured out my original problem. But now I have an even bigger problem.

First of all, I am trying to make a javascript implementation of Conway's Game of Life(CGoL). Now, for CGoL to work, you have to update all of the squares once, and only once without letting an update of an adjacent square impact it. Basically, I have to update all of the squares at the same time. How do I do that?

Here's my updated code:
 
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Rocky Rocha wrote:Basically, I have to update all of the squares at the same time. How do I do that?



You stash the updated values somewhere else, and then when you've calculated all of them, you copy them back to where the original values are.

Or alternatively: you copy all of the original values somewhere else, and then use the somewhere-else values to compute the new original values.
 
Rocky Rocha
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Thanks that works, but now I have another problem. How would I push an empty array into an array? Specifically, how do I push [] into simView.grid?
 
Rocky Rocha
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So right now my issue is that I cannot read the value of the 2D array. Here is my code.



What does this error mean, and how can I fix it?
 
It is sorta covered in the JavaRanch Style Guide.
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