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Array insert and remove functions

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12Me21Created:
These will work on any type of 1D array.

Insert

DEF INSERT ARRAY[],POS%,VALUE
 UNSHIFT ARRAY,VALUE 'This is just to make the array longer. I use VALUE since it will be the same variable type as the array.
 COPY ARRAY,ARRAY,1,POS% 'Moves all the elements before POS% 1 space to the left.
 ARRAY[POS%]=VALUE 'Add the new value.
END

Remove

DEF REMOVE ARRAY[],POS%
 COPY ARRAY,POS%,ARRAY,POS%+1,LEN(ARRAY)-(POS%+1) 'move all elements after POS% 1 space left.
 IF POP(ARRAY) THEN ENDIF'remove the last element.
END
ResourcesCode Snippets
Simeon#1
I have found this so useful, and have come back to this resource numerous times. It is much more efficient than looping through every element. I'm putting this minified code here for future reference, also because INSERT is 0.0006 milliseconds faster and REMOVE is 0.0012 milliseconds faster, that's right, faster than 12Me21 
'INSERT AN ITEM INTO AN ARRAY
DEF INSERT A[],I%,V
 UNSHIFT A,V COPY A,A,1,I% A[I%]=V
END

'REMOVE AN ELEMENT FROM AN ARRAY
DEF REMOVE A[],I%
 COPY A,I%,A,I%+1,LEN(A)-I%-1 I%=POP(A)
END
12Me21#2
Replying to:Simeon
I have found this so useful, and have come back to this resource numerous times. It is much more efficient than looping through every element. I'm putting this minified code here for future reference, also because INSERT is 0.0006 milliseconds faster and REMOVE is 0.0012 milliseconds faster, that's right, faster than 12Me21 
'INSERT AN ITEM INTO AN ARRAY
DEF INSERT A[],I%,V
 UNSHIFT A,V COPY A,A,1,I% A[I%]=V
END

'REMOVE AN ELEMENT FROM AN ARRAY
DEF REMOVE A[],I%
 COPY A,I%,A,I%+1,LEN(A)-I%-1 I%=POP(A)
END
The remove function won't work with string array, but yes, that version is faster for integer or float arrays.
Simeon#3
Replying to:Simeon
I have found this so useful, and have come back to this resource numerous times. It is much more efficient than looping through every element. I'm putting this minified code here for future reference, also because INSERT is 0.0006 milliseconds faster and REMOVE is 0.0012 milliseconds faster, that's right, faster than 12Me21 
'INSERT AN ITEM INTO AN ARRAY
DEF INSERT A[],I%,V
 UNSHIFT A,V COPY A,A,1,I% A[I%]=V
END

'REMOVE AN ELEMENT FROM AN ARRAY
DEF REMOVE A[],I%
 COPY A,I%,A,I%+1,LEN(A)-I%-1 I%=POP(A)
END
Oh yeah... you're right
Simeon#4
So I figured out, if you use these functions way too often, on huge arrays, they actually work in something like O(n/9000) time complexity, and slow down more and more But if you're only using INSERT and REMOVE on 0 or the end of the array for most of the time, this will make the function work in O(1) time complexity for those cases (which can be an absolutely huge performance increase depending on what you're doing). 
'INSERT AN ITEM INTO AN ARRAY
DEF INSERT A[],I%,V
 IF !I% THEN
  UNSHIFT A,V
 ELSEIF LEN(A)==I% THEN
  PUSH A,V
 ELSE
  UNSHIFT A,V COPY A,A,1,I% A[I%]=V
 ENDIF
END

'REMOVE AN ELEMENT FROM AN ARRAY
DEF REMOVE A[],I%
 IF !I% THEN
  IF SHIFT(A) THEN ENDIF
 ELSEIF LEN(A)==I% THEN
  IF POP(A) THEN ENDIF
 ELSE
  COPY A,I%,A,I%+1,LEN(A)-I%-1
  IF POP(A) THEN ENDIF
 ENDIF
END
It's a simple, self explanatory solution, but I just thought I'd point this out, since without it, my 3D engine takes about 12 extra seconds to start up, after lots of debugging this was the slowest part of my app, and this fix makes the startup time almost instant. Hope this helps someone!