Infinite loop problem?

#1 Posted: 8/6/2010 5:05:07 PM

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Hello Andrey,

I think this should be a bug.
[MATH]f(x)←5+f(x)[/MATH]
[MATH]f(1)=#[/MATH]
This will not stop executing until it is interrupted. I think this is an infinite loop problem.

Regards,
Radovan

When Sisyphus climbed to the top of a hill, they said: "Wrong boulder!"

#2 Posted: 8/6/2010 8:18:55 PM

Andrey Ivashov

2269 likes in 3730 posts.

Group: Super Administrator

Hello.

Thank you. Will check this later.

Regards.

#3 Posted: 8/18/2010 6:55:06 AM

Greg Locock

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Group: User

what behaviour would you expect?

you are asking for 5+5+5....

#4 Posted: 8/18/2010 7:27:35 AM

Radovan Omorjan

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Group: Moderator

Wrote
what behaviour would you expect?

you are asking for 5+5+5....

Yes, Greg, that is the problem. We can have something like this:
[MATH lang=eng]f(x)←x[/MATH]
[MATH lang=eng]f(x)←f(x)/2[/MATH]
[MATH lang=eng]f(5)=2.5[/MATH]
But with this, we get in trouble.
[MATH lang=eng]f(x)←f(x)/2[/MATH]
[MATH lang=eng]f(5)=#@#[/MATH]
The question is - Does it to be the user's problem to interrupt such a calculation or to suppress it by an error message? I was not sure about it, and that was my doubt about "endless loop".

Regards,
Radovan

When Sisyphus climbed to the top of a hill, they said: "Wrong boulder!"

#5 Posted: 9/29/2010 6:11:03 PM

Andrey Ivashov

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Group: Super Administrator

Fixed.

#6 Posted: 9/30/2010 3:10:33 AM

Radovan Omorjan

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Group: Moderator

Hello Andrey,

Sorry for being persistent, but I think I was not precise enough. The previous calculation will work in SMath - there was not a problem.
But, try this:

The problem is that this will never stop, until we "Interrupt processing". My question was - Should it be left this way or should it be stopped by SMath.

Regards,
Radovan

When Sisyphus climbed to the top of a hill, they said: "Wrong boulder!"

#7 Posted: 9/30/2010 8:52:55 AM

Andrey Ivashov

2269 likes in 3730 posts.

Group: Super Administrator

This is also fixed. Now SMath Studio understands that it is not good practice to repeat substitution of the already substituted functions with the same names

So one will not see infinite loops in such cases anymore.

Regards.

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Radovan Omorjan 9/30/2010 9:05:00 AM

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