[Scilab-users] add number arrays efficiently, how?

[Tim Wescott]

On Wed, 2017-03-22 at 15:15 -0700, Erhy wrote:
> Hello!
> I'm thinking in arrays - and I write
> 
> SumArr = [ 1 2 3 ];  toAdd = [ 7 8 9 10 ];
> SumArr( (length(SumArr)+1) : (length(SumArr)+length(toAdd)) ) =
> toAdd;
> 
> How to code it smarter?

That's probably the best way to append an array if you can't anticipate
ahead of time how big your ending array will be.  However, each time
you do that Scilab has to allocate space for a bigger array, copy, and
destroy the old copy of the array.

If you DO know how big your ending array will be, then you can speed
things up by creating a zero array of full size, then populating it as
you go.  I.e., in this case you'd create SumArr to be 1x7, then
populate the first three elements, then populate the last four.

-- 

Tim Wescott
www.wescottdesign.com
Control & Communications systems, circuit & software design.
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