Creating Unit vectors in a loop

Hey

I have a loop an I'm trying to create some unit vectors as follows:

e1 = [1;0;0;0;0;0;0;0]

e2 = [0;1;0;0;0;0;0;0]

e3 = [0;0;1;0;0;0;0;0]

all the way to

e7 = [0;0;0;0;0;0;0;1]

Thanks

[James Tursa]

1) Do you have to use a loop? Is that part of the assignment? There are easier ways to do this other than a loop.

2) You should not use e1 ... e7 as the variable names. This will create problems downstream in your code. I would suggest a cell array instead, e{1}, e{2}, ... , e{7}. This will make it easier to use indexing on these variables. E.g.,

https://www.mathworks.com/matlabcentral/answers/304528-tutorial-why-variables-should-not-be-named-dynamically-eval

Answer 1

[Shunichi Kusano]

Hi azarang,

The following code is an example

vecLength = 8;
I = eye(vecLength);
for i = 1:vecLength
    % save the vector as a field of the struct
    fieldname = ['e' num2str(i)];
    unitVectors.(fieldname) = I(:,i);
end

HTH

Answer 2

[James Tursa]

Since a complete answer has already been posted, I will post this one using a cell array result which will be much easier to index:

n = whatever length vectors you want
e = mat2cell(eye(n),ones(n,1),n);