Generate and Increment var names containing numbers and strings

Hello,

I'd like to generate a list of variable names where the output looks as follows:

# TB1W082A
# TB1W083A
# TB1W084A
# TB1W08AA
# TB1W08BA
# TB1W08CA
# TB1W092A
# TB1W093A
# TB1W094A
# TB1W09AA
# TB1W09BA
# TB1W09CA

Here is the code I'm using:

 % alph=('A':'C');
 % for n1 = 8:9
      for n2 = 1:3
        for a = 1:3
            num{n2} = ['TB1W' num2str(n1) num2str(n2+1) 'A'];
            str{a}  = ['TB1W' num2str(n1) alph(a) 'A'];
        end
      end
   end
clear a alpha n1 n2

I tried creating two variables; num and str. One was meant for the numeric portion and the other for the alphabetic portion. However, this is the output I get:

num =

1. TB1W092A
2. TB1W093A
3. TB1W094A

str =

1. TB1W09AA
2. TB1W09BA
3. TB1W09CA

Any suggestions?

[dpb]

Yeah, don't...see

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

for why not and how to do "the Matlab way" or if insist even the evil eval

Answer 1

[Matt Tearle]

See dpb's comment on why creating variable names like this is a bad idea, but... assuming you have a valid reason for creating strings in such a pattern:

Firstly, how general does this need to be? The twelve strings in your example are easily done with

x = {'2';'3';'4';'A';'B';'C'};
names = [strcat('TB1W08',x);strcat('TB1W09',x)]

Slightly more generally:

pre = 'TB1W';
names = {};
for k = 7:12
    names = [names;strcat([pre,num2str(k,'%02d')],x)];
end

Answer 2

[Dee]

Matt,

Thanks for volunteering your time. Your solution works very well. I guess I'm still baffled about why the embedded for loops didn't work. I guess that serves me right for trying to use so many of them. Thanks again.

[Matt Tearle]

The problem was that you were using your loop variables a and n2 as the indices to your arrays, so you are only ever assigning num{1}, num{2}, and num{3} (and ditto str). You were actually assigning them multiple times each, repeatedly overwriting them. To make your approach work, you'd need to keep an overall count variable going. Something along the lines of

k = 1;
for ...
   for ...
      for ...
         num{k} = ...
         k = k+1;
      end
   end
end