Calculate the best a angle

[D1vt]

As far as I understand, in order to calculate the best and worst angle a, you have to find the condition number of that covariance matrix:

Using the minimum condition number we can find the best a, and using the maximum condition number we can find the worse (-90<a<90) So I did that and 0.0 degrees are always the worst solution. But for the best a angle , I calculated it around 76 degrees (less than 90).

[D1vt]

Explain the whole Jacobian Matrix function. As R, R_Euler, t matrices I used the same as the code you send me (https://github.com/EgalYue/Mobile_Marker_Based_Navigation/blob/master/python/tracking_errors_theory/covariance_mat_sphericalCoordinate.py) :

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