MATLAB: Help in doing forward and backward difference…

backwarddifferencesforward

dv_dteta = zeros (length(crank_angle),1)

for j = 1:1:length(crank_angle-1) dv_dteta = (s(j+1)-s(j))./(crank_angle(j+1)-crank_angle(j)); end

when i write this i get an error code saying Index exceeds matrix dimensions.

the crank angle is a array of 300 data points.

is there a way to do a backward difference for the first point and the rest forward difference to match the dimensions???

Best Answer

You must use

j = 1:length(crank_angle)-1

rather then

   j = 1:1:length(crank_angle-1)

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Best Answer

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