Columns 10-12 of Kinematic Processing Output

Hello,
I have gathered from other questions on this forum that columns 7-9 [sdn(m), sde(m), and sdu(m)] of the POS output of kinematic processing correspond to the latitude, longitude, and altitude standard deviation, respectively, and I assume columns 10-12 [sdne(m), sdeu(m), sdun(m)] correspond to these in some manner? What do these columns measure?

Hi @mjsaenz,

Welcome to our forum!

The sdne, sdeu, and sdun are square roots of the absolute value of the NE, EU, or UN components of the estimated covariance matrix.

i have noticed that sdne, sdnu, sdeu can be negative, though. are they actually then square roots of the components? or is the sd matrix the “square root” of covariance matrix?

what i mean by that is, if sd is the standard deviation matrix, and cov is the covariance matrix, then
sd*sd = cov
where multiplication here denotes matrix multiplication?

1 Like

Hi @legalup,

They shouldn’t be negative because the standard deviation is the square root of the variance. The variance is the average of the squared differences from the mean value.

If you have such an example of the dataset, could you please send it to support@emlid.com? I’ll take a look into it.