1-Visitor

Question

Help Understanding Complex Matrix Calculations?

Forum|Forum|9 years ago
September 15, 2016
6 replies
2395 views

Hi,

The following matrix calculations were completed in Mathcad:

My feeling is that the vector solutions for the last two matrix x vector calculations should be equal. I would appreciate help understanding where I have made an error,

Thank You!

Rick

Other

M

MJG

1-Visitor

You are only seeing one significant digit of the second element in "pvi". I think its value is closer to 0.0095. When you use 0.0095 instead of 0.01, the result is much closer.

I think the other difference is that the first element of "pvi" is not equal to "pi". You calculated "pi" as (tot[1,1)*po. However, the first element of "pvi" is equal to (tot[0,0)*po. That is, unless you changed "ORIGIN" to 1.

R

rmcmullen

Author

1-Visitor

Hi Mark,

Thank you very much for your response. I am displaying more significant figures in my work because of your input.

Thank You!

Rick

21-Topaz II

Author

1-Visitor

Hi F.M.,

Thank you for your work to help me understand my mistake. The calculated pvi vector matches a known solution I have from another source. I will be more careful with the accuracy of numbers I input to the equations!

Thank You!

Rick

A

AlvaroDíaz

12-Amethyst

Hi.

You can try to solve the above system, with u-v solve a,b -> for example, to impose some conditions where the product was equal. But it is not for general values.

Best regards.

Alvaro.

R

rmcmullen

Author

1-Visitor

Hi Alvaro,

The rigorous symbolic representation of my problem that you presented helped me understand the different results I obtained in my calculations. I have the "origin" variable set to 1 for my matrix calculations but the point you make still applies.

Thank You!

Rick

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