how can propagate error for division of two matrices?

Question

Joseph 2018-6-13

0
链接

此问题的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/405382-how-can-propagate-error-for-division-of-two-matrices

评论： Joseph 2018-7-19

I have two arrays E(i,j,k) and E_2(i,j,k) in which some elements of these matrices are nan values. while, I can calculate standard deviations S(i,j) = nanstd(E(i,j,:)); and S_2(i,j) = nanstd(E_2(i,j,:)); for E and E_3, i don't know howe to calculate standard deviation for E_2(i,j,k)./E(i,j,k). i was wondering if it is possible using propegation of error (function sigma = PropError(f,varlist,vals,errs)) or any other way.

Thank you in advance

0 个评论
显示 -2更早的评论隐藏 -2更早的评论

请先登录，再进行评论。

请先登录，再回答此问题。

Answer 1

Arvind Narayanan 2018-7-6

0
链接

此回答的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/405382-how-can-propagate-error-for-division-of-two-matrices#answer_327731

Hi Joseph,

If the second matrix(E(i,j,k) in this case) has all non zero elements(NaN allowed), then only we can calculate standard deviation of this p./q type matrix. Otherwise, the resulting matrix will have Inf in it which would result in standard deviation in NaN .

Since Inf makes the mean and other central tendencies of the matrix non-quantifiable, the result is NaN.

For matrix with non-zero elements, we can use p./q and then use nanstd to find standard deviation.

Hope this helps,

Arvind

1 个评论
显示 -1更早的评论隐藏 -1更早的评论

Joseph 2018-7-19

These two matrices are measurements with the known error for each element. lets say for matrix E(i,j,k) there is an error(i,j,k) matrix. and same for E_2 matrix. I didn't mention this in my question.

请先登录，再进行评论。