Subscript indices must either be real positive integers or logicals

x = tudo(:,2)
y = tudo(:,1)
w = tudo(:,3)

% normalize ships
min_x = min(x)
max_x = max(x)
norm_nav = (x - min_x)/(max_x - min_x)
tudo_norm(:,1) = norm_nav

% normalize hours
min_y = min(y)
max_y = max(y)
norm_horas = (y - min_y)/(max_y - min_y)
tudo_norm(:,2) = norm_horas

% normalize poff
min_w = min(w)
max_w = max(w)
norm_poff = (w - min_w)/(max_w - min_w)
tudo_norm(:,3) = norm_poff

% matrix A
A(:,1) = tudo_norm(:,3)

% matrix B
B(:,2) = norm_nav
B(:,3) = norm_horas
B(:,1) = 1

% matrix C
C = sym('C', [3 1])

% coefficients
transposed = B.'
BB = B.' * B
inverse = inv(B.' * B)
C = inv(B.' * B) * B.' * A

% W = D + AX + BY
T = C(1,1) + C(2,1) * norm_nav + C(3,1) * norm_horas

% RMSE 
erro = T - norm_poff
sqerr = erro.^2
msqerro = mean(sqerr)
rmse = sqrt(msqerro)

% standard deviation
d_padrao = std(T)
% (SSE)
sse = sum(erro.^2)
xx = sse / (tamanho-3)

%-------------------------------------------

% TESTING

% Enter desired data
Navios = 3     
Horas = 1     

% New max an min?
if Navios > max(x)      % max e min de x
    max(x) = Navios
else
    if Navios < min(x)
        min(x) = Navios
    end
end

if Horas > max(y)       % max e min de y
    max(y) = Horas
else
    if Horas < min(y)
        min(y) = Horas
    end
end

% normalize new
navio = (Navios - min_x)/(max_x - min_x)
hora = (Horas - min_y)/(max_y - min_y)

max_navio = max(x)
max_hroas = max (y)
max_poff = max(w)

W = C(1,1) + C(2,1) * navio + C(3,1) * hora

% RMSE 
erro = W - norm_poff
sqerr = erro.^2
msqerro = mean(sqerr)
rmse = sqrt(msqerro)

% (SSE)
sse = sum(erro.^2)
xx = sse / (tamanho-3)

POFF = (W*(max_w - min_w)) + min_w

Hello guys, I'm currently developing a code to the prediction of some data. However I have a problem. When intend to test the code, and enter the desired data, when I type the variable "Navios" = 1 the following error appears:

Subscript indices must either be real positive integers or logicals Error in ==> Modelo_2VAR at 90      if horas <min (y)

I do not understand why this error appears.

Someone help me?

Answer 1

[Azzi Abdelmalek]

There is a problem with the lines of code containing:

      max(x) = Navios
      min(x) = Navios

max and min are built-in functions, you can't use them as variables

Answer 2

[Walter Roberson]

if Navios > max_x      % max e min de x
    max_x = Navios
else
    if Navios < min_x
        min_x = Navios
    end
end

if Horas > max_y       % max e min de y
    max_y = Horas
else
    if Horas < min_y
        min_y = Horas
    end
end

[Luis Meneses]

Thank you.

But nevertheless, when I change the value of "Navio" from 0, 1, 2 and 3, the result does not change ... Why does it happen?