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Scaling problems for Array.slice on large arrays

1 reply
Sat, 2009-01-24, 10:50
tolsen77
Joined: 2008-10-08,
User offline. Last seen 1 year 38 weeks ago.
I've been using Array[Byte] for storing images and using Array.slice to clone them, but noticed apperant delays in my program whenever I used it.

Could it be an idea to add System.arraycopy as an optimization for the JVM?
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Sat, 2009-01-24, 12:17
#1
odersky
Joined: 2008-07-29,
User offline. Last seen 45 weeks 6 days ago.
Re: Scaling problems for Array.slice on large arrays

Array.slice gives you a projection (i.e forwareder to old array)
rather than a new array. This can affect algorithmic complexity. If
you want a new array, use Array.copy, with parameters as in
System.arrayCopy.

Btw, I believe this design of slice was a mistake. In 2.8, slice will
give you a new array, to get a projection, you'll have to write
.view.slice.

Cheers

- Martin

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