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Hello,

I have time, t on the x axis and power, Pw on the y axis. I want to compute the following equations for only times, t where Pw is positive. How can I do that?

% calculating alphar dependent on t

for tidx = 2:length(t)-1

alphar = Cr(tidx).*Mv*g

end

% calculating three summation terms

x = 0;

for tidx = 2:length(t)-1

x = x+(V(tidx)).^3;

end

y=0;

for tidx = 2:length(t)-1

y = y+V(tidx);

end

z=0;

for tidx=2:length(t)-1

z = z+(V(tidx)*(V(tidx+1)-V(tidx-1)));

end

% Want to calculate below equation only for t at Pw>0 (Pw calculation shows below)

Ew = (1369*((alphaa*x)+(alphar.*y)+(alphai*z)))/1000 % alphaa and alphai are constants. alphar is only one dependent on t (shown first line above)

Pw calculation shows below

for tidx=2:length(t)-1

a = (V(tidx+1)-V(tidx-1))/(2*(t(tidx+1)-t(tidx-1)));

A = ((1/2)*Rhoa*Cd*Af*(V(tidx).^3));

G = (Cr(tidx).*Mv*g*cos(0).*V(tidx));

I = (1.1*Mv.*a.*V(tidx));

Pw(tidx-1) = (A+G+I)/1000;

end

darova
on 21 Sep 2019

Take Ew where Pw>0

Ew = (1369*((alphaa*x)+(alphar.*y)+(alphai*z)))/1000 % alphaa and alphai are constants. alphar is only one dependent on t (shown first line above)

Ew1 = Ew(Pw>0);

darova
on 21 Sep 2019

That isn't performing the summation

% Want to calculate below equation only for t at Pw>0 (Pw calculation shows below)

The question: do x,y and z depend on t? What is value of x at specific t?

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https://in.mathworks.com/matlabcentral/answers/481475-how-to-compute-equation-only-for-x-y-0#comment_748473

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