I am getting a sparse error in my Matlab code

for i=1:9
    for j=1:9
        D[i][j]=[0]  This line
        D[1][1]=[E*A]
        D(2)(2)=G*Asy
        D(3)(3)=G*Asz
        D(4)(4)=G*Jt
        D(5)(5)=E*Iy
        D(6)(6)=E*Iz
        D(7)(7)=1/mu*E1*Jt
        D(8)(8)=E1*Jd
        D(9)(9)=E1*J11

[madhan ravi]

select the whole code and press the code button

[Adam Danz]

If this is your entire code except for the two ends you're missing, you don't need to use loops at all. If you want useful feedback you'll need to upload the rest of the loops and format it correctly using the { } button.

[Virajan Verma]

This is the whole program

%%Input file for Mass Matrix
fid=fopen('input3.txt','r');
Data=fread(fid);
CharData=char(Data);
fclose(fid);
disp(CharData);

%%Mass Matrix

M=r*A;
M=[M*eye(9)]

%%Input file for D Matrix
fid=fopen('input4.txt','r');
Data=fread(fid);
CharData=char(Data);
fclose(fid);
disp(CharData);

%%Rigidity Matrix

for i=1:9

      for j=1:9

          D[i][j]=[0]
          D[1][1]=[E*A]
          D(2)(2)=G*Asy
          D(3)(3)=G*Asz
          D(4)(4)=G*Jt
          D(5)(5)=E*Iy
          D(6)(6)=E*Iz
          D(7)(7)=1/mu*E1*Jt
          D(8)(8)=E1*Jd
          D(9)(9)=E1*J11

%%Output file for D Matrix
fid=fopen('OUTPUT3.txt','w');
fprintf(fid,'%d\n',D[i][j]);
fprintf(fid,'%d\n',D[1][1]);
fprintf(fid,'%d\n',D(2)(2));
fprintf(fid,'%d\n',D(3)(3));
fprintf(fid,'%d\n',D(4)(4));
fprintf(fid,'%d\n',D(5)(5));
fprintf(fid,'%d\n',D(6)(6));
fprintf(fid,'%d\n',D(7)(7));
fprintf(fid,'%d\n',D(8)(8));
fprintf(fid,'%d\n',D(9)(9));

fclose(fid);
    end
end

[madhan ravi]

Forgot to upload the file/s.

Answer 1

[Jishnu Mukherjee]

if you are trying to fill the D matrix then try something like this

D=zeros(9,9);
for i=1:9 
    for j=1:9 
    D(i,j)=0;
    end
end

use () braces instead of []