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Why does this article state that \beta has a range "covers π radians (but can't be said to be modulo π)"?

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This is about section 2.4 "Signs, ranges and conventions". Given the (sensible) definition in the previous section, \beta is an unsigned angle between two vectors. Hence it's in the range [0,\pi]. But someone made the effort to write something more complicated, so there seems to have been some thinking behind it. Some point I'm missing (which IMHO no longer fits the text). Any idea why the text makes this complicated statement? Is there anything of value here that should be preserved?

It can not be said to be modulo pi because [0,pi] here is a closed interval. The other angles are really modulo 2.pi because they are open intervals in one of the extremes, for example [0, 2pi), using parenthesis to express the open side.

There are not enough marine names and definitions of angles.

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There are not enough marine names and definitions of angles. I am sure that sailors have different standards of angles, not the same as in aviation. Совместный труд таких (talk) 08:18, 13 April 2022 (UTC)[reply]

Proposal: Changing "proper" by "classic"

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Speaking about "proper Euler angles" gives a sensation of something improper in Tait-Bryan convention. Maybe it could be changed by something like "classic Euler angles".

--Juansempere (talk) 10:33, 25 January 2023 (UTC)[reply]

As nobody opposes, I am going to perform the change Juansempere (talk) 11:44, 9 February 2023 (UTC)[reply]

tait-bryant angles

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The computational formulas for Tait-Bryan are not entirely correct, the book is referenced wrongly you should stick to all angles by tan operator e.g. ZXY - b = arcsin(R_12) should be with more correct one ZXY - b = atand(R_32./(sqrt(R_31.^2 + R_33.^2)) and took consideration when the denominator is 0 accordingly 86.114.45.241 (talk) 10:17, 1 February 2024 (UTC)[reply]

Sorry, there is mistake for the rotation axis order, should be ZXY
Proof:
beta = sin^-1(R_32) = atan(R_32/sqrt(R_31^2 + R_33^2) =
= atan(s_2/(sqrt(c_2^2s_3^2+c_2^2c_3^2) =
= atan(s_2/c_2 sqrt(s_3^2 +c_3^2) =
= atan(s_2/c_2 sqrt(1) = atan(s_2/c_2) 86.114.45.241 (talk) 09:08, 2 February 2024 (UTC)[reply]

Euler angles from rotation matrices

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The formulas to calculate Euler angles from the rotation matrices are wrong. They should feature the atan2 function instead of arctan, which does not span over the entire angular range. EFlexul (talk) 21:30, 6 May 2024 (UTC)[reply]