Arrays have incompatible sizes for this operation.

Hello! I want to calculate the acceleration but there's error which is I don't know what's need to be amend .

All the array here have the same dimension which is 1x47

s2= sind([-23.155386 -23.124987 -23.104193 ...])

s3= sind([38.535091 39.562313 40.583305 ...])

c2=cosd([-23.155386 -23.124987 -23.104193 ...])

c3=cosd([ 38.535091 39.562313 40.583305 ...])

c4=cosd([86.32077 86.347443 86.42453 ...])

s4=sind([86.32077 86.347443 86.42453 ...])

s5=sind ([ -35.981091 -36.282097 -36.616375 ...])

c5=cosd([-35.981091 -36.282097 -36.616375 ...])

c6=cosd([-29.205807 -29.200783 -29.196812 ...])

s6=sind([-29.205807 -29.200783 -29.196812 ...])

c7=cosd([-37.455574 -37.206734 -36.926373 ...])

s7=sind([-37.455574 -37.206734 -36.926373 ...])

diff_q1t=[-0.752469036 -0.785655599 -0.821694903 ...])

diff_q2t=[0.057738982 0.04467432 0.024727825 ...])

diff_q3t=[1.798555686 1.787403904 1.77699127 ...])

diff_q4t=[-0.204530772 -0.170022994 -0.123331074 ...])

diff_q5t=[-0.441452236 -0.443240326 -0.451332545 ...])

diff_q6t=[-0.016948892 -0.003593633 0.004956735 ...])

diff_q7t=[0.349886155 0.354433611 0.363348752 ...])

diff_q1t_second_derivative = diff(diff_q1t)

% Time array

time = (-0.4:0.01:0.06)

% here is my equation for acceleration

NaAstar_a1 = ((pA.*(s3.*diff_q2t + c2.*c3.*diff_q1t) - pA.*(s2.*diff_q1t + diff_q3t)).*(s2.*diff_q1t + diff_q3t) - pA.*(c2.*s3.*diff_q1t_second_derivative - c3.*diff_q2t + s3.*diff_q3t.*diff_q2t + c2.*c3.*diff_q3t.*diff_q1t - s2.*s3.*diff_q2t.*diff_q1t) - pA.*(s2.*diff_q1t_second_derivative + c2.*diff_q2t.*diff_q1t + diff_q3t + (pA.*(s3.*diff_q2t + c2.*c3.*diff_q1t) - pA.*(c3.*diff_q2t - c2.*s3.*diff_q1t)).*(c3.*diff_q2t - c2.*s3.*diff_q1t)));

[Dyuman Joshi]

"All the array here have the same dimension which is 1x47"

Incorrect, this is not 1x47, it is 1x46.

diff_q1t_second_derivative = diff(diff_q1t)

[Syazana]

I'm using this numel function to check the number of elements in the time array and all the variable contains 47 elements

disp(numel(time)) % Display the number of elements in the time array

disp(numel(s3)) % Display the number of elements in the s3 array

[Dyuman Joshi]

"... all the variable contains 47 elements"

No, as I said earlier as well, the variable "diff_q1t_second_derivative" is not 1x47. You can check it.

[Syazana]

Oh ya sorry for misundertsanding, then how I can set the second derivate of diff_q1t to be the same array as diff_q1t? Is it true if I set like this since the -1.4454 is the min number in the diff_q1t

diff_q1t_second_derivative = diff([-1.4454 diff_q1t])

[Dyuman Joshi]

You can put any number there, but the final output value(s) will depend on the number.

You can also use gradient instead of diff