MATLAB: Summing parts of an array?

matrixmatrix arraymatrix manipulation

I have the following lines of code:

D=(8./(TSR.*9)).*(F.*(sin(relative_wind).^2).*(cos(relative_wind)-((TSR_local).*(sin(relative_wind)))).*(sin(relative_wind)+((TSR_local).*(cos(relative_wind)))).*(1-(Cd./Cl).*cot(relative_wind)).*(TSR_local.^2));
Cp=sum(D);

D is a 9×1 array. However I only want to sum the first 8 values in the array. Could anybody please show me how to do this as my current code is summing all 9 values?

Best Answer

sum(D(1:8))

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%initial values not specified, gotta invent some
rng(1234);
r1 = rand; r2 = rand; r3 = rand; r4 = rand; r5 = rand; r6 = rand; r7 = rand; r8 = rand; r9 = rand; r10 = rand; r11 = rand; r12 = rand; th2 = rand; gam1 = rand;
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opt = optimoptions('fsolve','MaxFunctionEvaluations', 1e7, 'MaxIterations', 1e6);
[H, fval] = fsolve(sys, G, opt);
disp(H)
disp(fval)

Best Answer

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