Any commands about rotation where the unit of the input is radian

Hi there,

We find in Matlab, the command rotx denotes a rotation matrix around the x-axis by ang degrees, and the unit of the input is degree.

Here I want to ask, are there any commands that the unit of the input is radian?

Many thanks!

Answer 1

[the cyclist]

I don't think there is a native equivalent of rotx() that uses radian as input. You can convert radians to degrees using the rad2deg function. You could write your own rotx_rad() function that incorporates that automatically.

function R = rotx_rad(theta_rad)
% Rotation matrix about the x-axis (input in radians)
%   R = rotx_rad(theta_rad) returns the 3×3 rotation matrix for a rotation
%   of theta_rad radians about the x-axis.

    % Convert radians to degrees and call rotx()
    R = rotx(rad2deg(theta_rad));
    
end

Answer 2

[Paul]

eul2rotm and angle2dcm both ingest angle inputs in radians, but they both require three angles on input. Also, care must be taken when using the output because the functions return different matrices.

eul2rotm([pi/4,0,0])

ans = 3×3

0.7071 -0.7071 0 0.7071 0.7071 0 0 0 1.0000

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angle2dcm(pi/4,0,0)

ans = 3×3

0.7071 0.7071 0 -0.7071 0.7071 0 0 0 1.0000

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