Coding an Equation with Sum of including limitations

Hi All,

Im just having trouble writing an equation in matlab that will match the following equation given. I have the values of vx and x1 imported in my data but am not sure how to write the equation so that after the value for k is input it can create such an equation. Eg if i were to input input 3 in the command window the equation should be solved as x(3) = (vx(2)(t(3)-t(2)))+(vx(1)(t(2)-t(1)))+x1. Thank you in advance

[Deepak Gupta]

x(k) = sum(vx(2:end)-vx(1:end-1))+x(1)

Answer 1

[Antoine Laurin]

This is unclear.

What is vx (or vxj) ? A vector ?

What is tj ? A scalar ? An integer ?

Do you want to multiply the value of vxj by the difference (tj+1 - tj) ? Or do you want to access the value of vxj for the index defined by the difference (tj+1 - tj) ?