solve a equation system with a 1xn matrix

Hello,

I got a problem with my code:

FF = 100
psi1 = [1:148]
syms G7_x G7_y C_x C_y D_x D_y
g01 = D_x+FF*cos(psi1) == 0
g02 = D_y+FF*sin(psi1) == 0
g1 = G7_x-FF*cos(psi1) == 0
g2 = G7_y-FF*sin(psi1) == 0
g3 = -G7_x-C_x == 0
g4 = -G7_y-C_y == 0
k=zeros(1,148)
l=zeros(1,148)
s=zeros(1,148)
d=zeros(1,148)
f=zeros(1,148)
g=zeros(1,148)
for i=1:148
[sol_G7_x, sol_G7_y, sol_D_x, sol_D_y, sol_C_x, sol_C_y] = vpasolve([g01(i), g02(i), g1(i), g2(i), g3(i), g4(i)],[G7_x, G7_y, D_x, D_y, C_x, C_y])
k(i)=sol_G7_x
l(i)=sol_G7_y
s(i)=sol_D_x
d(i)=sol_D_y
f(i)=sol_C_x
g(i)=sol_C_y
end

The first passing of the loop works and puts out values. After the first passing the code ends with the following error message:

Index exceeds matrix dimensions.
Error in sym/subsref (line 841)
          R_tilde = builtin('subsref',L_tilde,Idx);
Error in TESTTEST (line 20)
[sol_G7_x, sol_G7_y, sol_D_x, sol_D_y, sol_C_x, sol_C_y] = vpasolve([g01(i),
g02(i), g1(i), g2(i), g3(i), g4(i)],[G7_x, G7_y, D_x, D_y, C_x, C_y])

I hope anybody can help me. I use the matlab version R2017a.

Answer 1

[Walter Roberson]

Your g3 and g4 have only one element each, so when i becomes 2 because of your for loop, you cannot do

[sol_G7_x, sol_G7_y, sol_D_x, sol_D_y, sol_C_x, sol_C_y] = vpasolve([g01(i), g02(i), g1(i), g2(i), g3(i), g4(i)],[G7_x, G7_y, D_x, D_y, C_x, C_y])

because of the attempt to access g3(2) and g4(2)