MATLAB: Getting Subscripted assignment dimension mismatch.

assignment dimension mismatcherrorloopsubscripted

my codes are as follow :
when i use this , the loop works
for i=1:3
vec=(1+i):(2+i);
mat(i,:)=vec;
vec=[];
end
EDU>> mat
mat =
     2     3
     3     4
     4     5
but when i use this , it shows the error message Subscripted assignment dimension mismatch.
EDU>> for i=1:3
vec=(1+i):(3+i);
mat(i,:)=vec;
vec=[];
end
Subscripted assignment dimension mismatch.
EDU>> for i=1:5
vec=(1+i):(3+i);
mat(i,:)=vec;
vec=[];
end
Subscripted assignment dimension mismatch.
how can i rectify this ? i need this concept for a huge loop and it shows similar error message when i run my code the matrix generally runs until 5th or 6th row
HELP PLEASE !!!

Best Answer

Hi,
if you do
for i=1:3 
    vec=(1+i):(2+i); 
    mat(i,:)=vec; 
    vec=[];
end
for i=1:3 
    vec=(1+i):(3+i); 
    mat(i,:)=vec;
    vec=[]; 
end
the you get an error.
You need to clear your workspace or define the mat variable before the loop
for i=1:3 
    vec=(1+i):(2+i); 
    mat(i,:)=vec; 
    vec=[];
end
clear mat
  for i=1:3 
      vec=(1+i):(3+i); 
      mat(i,:)=vec;
    vec=[]; 
end
The error occurs because after the first loop, mat is a matrix with 2 columns.
And in the second loop, you use a 3 element vector vec to fill the line.
so the dimensions mismatch.
Note : you should put your question in code form, so it is more readable for everyone.
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