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10-26-2017
03:49 PM

10-26-2017
03:49 PM

Length-1 Vector Multiplication Error

I have found an error in vector multiplication when the length of one vector is reduced to just one. It should not throw an error, but does, stating that "These array dimensions do not match", which is just ridiculous.

Of course, there are workarounds, but this should be corrected.

Thoughts anyone?

4 REPLIES 4

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10-26-2017
04:43 PM

10-26-2017
04:43 PM

Re: Length-1 Vector Multiplication Error

Nukeman,

I agree that the symbolic processor has a bug. However, please note that the numeric processor calculates the correct product.

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10-26-2017
05:12 PM

10-26-2017
05:12 PM

Re: Length-1 Vector Multiplication Error

Mostly correct. However, the Lev-Mar method (in genfit and Least SquaresFit) has to resolve the first derivatives of the fitting parameters. That's where I've run afoul of this problem.

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10-26-2017
05:13 PM

10-26-2017
05:13 PM

Re: Length-1 Vector Multiplication Error

How does it fare when the vector (with the lower case letters) is reduced to a single element vector (containing just a)?

In Mathcad 11:

Luc

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10-26-2017
05:26 PM

10-26-2017
05:26 PM

Re: Length-1 Vector Multiplication Error

Yes, Prime produces this same result. But, this is still only half right.

Thanks for checking.