Using strings as variable names in a for loop

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What I would like to do is:
K2006=20;
k2007=30;
years={'2006','2007'}
for i = 1:2
mystr=strcat('K',years{i})
myvar=genvarname(mystr)
C=zeros(myvar)
...
end
But the last command does not work, I get an error message saying:
Error using zeros Trailing string input must be a valid numeric class name.
Can anybody help me to fix it?

Accepted Answer

Thorsten
Thorsten on 29 Oct 2015
Edited: Thorsten on 29 Oct 2015
You can use
eval(['C=zeros(' myvar ');'])
But it would be much simpler to code
k = [20, 30];
for i = 1:numel(k)
C = zeros(k(i));
end
If you need the year
year = [2006, 2007]
then k(i) is the value of year(i).

More Answers (1)

TastyPastry
TastyPastry on 29 Oct 2015
Have you tried stepping line by line using the debugger? You'll notice that in the line
C=zeros(myvar);
You're trying to create a vector of zeros with 'myvar', which is a string. You can't call zeros() with a string input.
Why don't you just create a cell array which holds K2006, K2007 and their respective values? That way, you can just loop through the cell array.
  2 Comments
Thorsten
Thorsten on 29 Oct 2015
Edited: Thorsten on 29 Oct 2015
It's not a good idea to code your data this way. Simply define variables K, g and so on as a vector of numbers, one for each year, as I've detailed in my answer below.

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