Using string saved variables for calculations

If I have variables with varying names (Z_1,Z_2,Z_3,etc) with assigned values of z made by num2str as shown below;

for v=1:18
    eval(['Z_' num2str(v) '=z'])
    end

and each has stored a matrix inside (Z_1 is a 10x10 matrix, and so on for each Z_n), and I want to sum up the matrices without having to enter TotalZ=Z_1+Z_2+Z_3...Z_18, is there any quick way of referring to the variables? I mean, something of the kind of :

TotalZ=sum('Z_'num2str(v))

 I can't seem to find a way of using those stored variables to o anything, if I dont enter them directly by hand. I need to know the right way of referring to the variables for using them for any calculation. Thanks in advance.

Answer 1

[Titus Edelhofer]

Hi,

generally speaking you can do the same as before:

TotalZ = 0;
for v=1:18
  TotalZ = TotalZ + eval(['Z_' num2str(v)]);
end

But I would suggest to use cellarrays directly:

allZ = cell(1, 18);
for v=1:18
all{v} = z;
end

Working with the cell array later will be much easier, e.g.,

allZ3D = cat(3, allZ{:});
TotalZ = sum(allZ3D, 3);

Titus

[Guillermo Lopez]

Thank you very much. Works well

Answer 2

[Walter Roberson]

http://matlab.wikia.com/wiki/FAQ#How_can_I_create_variables_A1.2C_A2.2C....2CA10_in_a_loop.3F