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  • 1 Post By romsek
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August 26th, 2019, 01:43 AM   #1
Joined: Sep 2013

Posts: 93
Thanks: 2

Intlab help


Can anyone tell me why this command doesn't work? Two days ago it worked... I don't really understand how can someone ask so much money for such a bugged software

y=sin(x); this generates error:

Dot indexing is not supported for variables of this type.
Error in modpi2>modpi2fast (line 73)
x = ( x + (-k)*INTLAB_INTVAL_STDFCTS_PI.PI2_1 ) + ... % exact for abs(x)<=2^27
Error in modpi2 (line 41)
[ yinf , ysup , s , index ] = modpi2fast(x);
Error in intval/sin (line 46)
[ xinfinf , xinfsup , Sinf ] = modpi2(x.inf( : ));
ricsi046 is offline  
August 26th, 2019, 09:10 AM   #2
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Joined: Sep 2015
From: USA

Posts: 2,553
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I'm no expert but the online command reference makes it look like the return of

infsup(1,2) = [1,2]

You probably can't pass an interval type to the sin() function.

Sorry if I'm totally out in left field. Never used the software before.
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September 2nd, 2019, 09:56 AM   #3
Joined: Sep 2013

Posts: 93
Thanks: 2

Hardly anyone interested most likely, but who knows, I will share it anyway.
I finally found the problem, this version of intlab is not compatible with my matlab, so I downloaded another matlab and it works

>> infsup(1,2)
intval ans =
[ 1.0000, 2.0000]
>> cos(ans)
intval ans =
[ -0.4162, 0.5404]

Thanks for trying to help
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