can not get values

i built this mathimaticly project of tram running simulation , but there is no error and at the same time there is no output values (all values are zero), would u please help me and diagnose the matter ?

Answer 1

[Daníel Freyr Hjartarson]

You were overwriting you calculations of a,v and s. I created matrices to save your results instead. That gives you a better overview of your timesteps. But your problem seems to be in the interpolation you are doing the first NaN is returned by the call interp1(R(:,1), R(:,2), t). It's unclear for me what you are interpolation between, could you give some more information on that?

%% Starting calculation
a_res = zeros(100,100);
v_res = zeros(100,100);
s_res = zeros(100,100);

for t = 1:100
    w0 = interp1(W0(:,1), W0(:,2), v);
    
    if interp1(R(:,1), R(:,2), t) > 0
        R = interpl(R(:,1), R(:,2), t);
        wR = 600*m*g/(R - 55);
    else
        wR = 0;
    end
    
    inc = interp1(INC(:,1), INC(:,2), s);
    w_inc = inc*m*g;
    w_sum = w0 + w_inc + wR;
    
    if (v < vmax) && (s < Sstop - Sbraking)
        F = interp1(TE(:,1), TE(:,2), v);
    elseif (v >= vmax) && (s < Sstop - Sbraking)
        F = w_sum;
    elseif s >= Sstop - Sbraking
        F = 0;
    end
    
    a = (F - w_sum)/m*(1 + K);
    v = v + a;
    s = s + a*t;
    i = interp1(I(:,1), I(:,2), v);
    P = U*i;
    efficiency = F*v / P ;
    E = P*t;
    
    %saving the results of calculation
    a_res(:,t) = a;
    v_res(:,t) = v;
    s_res(:,t) = s;
end

Answer 2

[Mark Sherstan]

Your data set and interplation dont line up. The R variable you define is:

R =

         379          24
        1000          56
        1180         110
        1300          72
        2360        1170
        2990         328
        6200         154
        6320         192
        9149         283
        

Looking at the first couple loops t will be 1, 2, 3, ...

interp1(R(:,1),R(:,2),t)

t has nothing to interpolate to. It is not bounded by any values and will output "nan" which forces your if statment:

if interp1(R(:,1),R(:,2),t)>0
    R=interpl(R(:,1),R(:,2),t);
    wR=600*m*g/(R-55);
else
    wR=0;
    
end

To output a zero answer. Try fixing up your data sets and solve the first couple itterations by hand to make sure everything makes sense.