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Index › Programming Questions & Help › Syntax Questions › array length not changed after append
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array length not changed after append? (Read 1250 times)
wmw
array length not changed after append?
May 27th, 2010, 2:05am  
Hi -
I'm trying to repopulate an array:
void setup(){
size(200,200);
}
void draw(){
int[] a = new int[0];
//expand(a,1);
append (a,1);
text (a.length,100,100);
noLoop();
}

It prints 0, while I'd expect the array length to be 1, after the append operation. Also, trying to access a[0] gives an array boundary error.
What am I doing wrong or where might I be misunderstanding the effect of append?

My actual goal is to have an array that can be repopulated, with a varying number of elements between 'frames'. How do I do that?

Thanks in advance,
wmw.
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PhiLho 
Re: array length not changed after append?
Reply #1 - May 27th, 2010, 2:23am  
Let see append() reference...
String[] sa2 = append(sa1, "MA ");
Note that append "Expands an array by one element and adds data to the new position" but it is ambiguous because actually it creates a new array instead of expanding it, so you need to assign the result of append, either to a new array as shown, or to the old array:
a = append(a, 1);
Perhaps they should have stated that more explicitly than just giving an example...
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WWW  
wmw
Re: array length not changed after append?
Reply #2 - May 27th, 2010, 2:46am  
aha! Thanks a bunch, PhiLho! Guess that wasn't indeed quite as obvious from the dox. a = append(a,1); works perfectly!
Regards,
wmw.
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