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Topic: Matrix dimensions must agree.
Replies: 13   Last Post: Mar 24, 2014 5:34 PM

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dpb

Posts: 8,163
Registered: 6/7/07
Re: Matrix dimensions must agree.
Posted: Mar 21, 2014 2:10 PM
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On 3/21/2014 10:40 AM, dpb wrote:
> On 3/21/2014 8:46 AM, Steven Lord wrote:
...

>> I wouldn't use this approach; I'd instead select the elements to keep.
>> It avoids the IF and ELSEIF statements at the expense of a call to MIN:
>>
>> minRows = min(x, y);
>> a = a(1:minRows, :);
>> b = b(1:minRows, :);
>>

> ...
>
> It then also has the cost of the selection on both where one is already
> ok that the if...elseif avoids which is why I went that route.

...

I'm presuming the ML JIT optimization can't tell the above copy doesn't
need to happen, of course. Is the runtime code generation that smart,
Steven?

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