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From: Delia on 4 Jun 2010 19:25
Hi, I want to use the name of a variable as a string (for example as xlabel of a plot). How do I do that?.
I kind of what to achieve this:
x = [1 2 3]
plot(x)
xlabel('x')
without using the explicit name of the variable in the last line (assume I loop over many variables and I do not the name).
Thank you for the help
delia
From: Walter Roberson on 4 Jun 2010 23:36
Delia wrote:
> Hi, I want to use the name of a variable as a string (for example as
> xlabel of a plot). How do I do that?. I kind of what to achieve this:
> x = [1 2 3]
> plot(x)
> xlabel('x')
> without using the explicit name of the variable in the last line (assume
> I loop over many variables and I do not the name).

In order to assume that you are looping over variables, I have to assume
that you have the name of the variable somehow, in which case you do not
have any difficulty in using the name as a string.

The only way I can see at the moment that might throw things off is if
you are looping over components of a symbolic expression, and you have a
symbol whose _value_ is the name of another symbol. I do not have the
symbolic toolbox to test out that case, and it is different enough from
your example that it seems unlikely.

How _exactly_ are you looping over variables without having the name of
a variable in a string already?

If you are making a function call and passing in eval() of the name of a
variable, and you want to recover that name, then _possibly_ inputname()
might do the trick for you, but I would not count on it, as I would
expect that Matlab would consider eval() of something to be an anonymous
expression that had no name.

I get the impression that what you are probably really after is
something that you should be avoiding. See
http://matlabwiki.mathworks.com/MATLAB_FAQ#How_can_I_create_variables_A1.2C_A2.2C....2CA10_in_a_loop.3F
From: Rajiv Narayan on 4 Jun 2010 23:53
"Delia " <deliatosi(a)hotmail.com.remove.this> wrote in message <huc210$kc9$1(a)fred.mathworks.com>...
> Hi, I want to use the name of a variable as a string (for example as xlabel of a plot). How do I do that?.
> I kind of what to achieve this:
> x = [1 2 3]
> plot(x)
> xlabel('x')
> without using the explicit name of the variable in the last line (assume I loop over many variables and I do not the name).
> Thank you for the help
> delia

Its probably best if you use arrays or cells, instead of having separate variables.
If your variables are named in a deterministic fashion, you could try something like:

d1 = rand(10,1);
d2 = rand(10,1);
v = who('d*');
for ii=1:length(v)
figure
plot(eval(v{ii}));
xlabel(v{ii});
end
From: sscnekro on 5 Jun 2010 06:20
> Hi, I want to use the name of a variable as a string (for example as xlabel of a plot). > without using the explicit name of the variable in the last line (assume I loop over many variables and I do not the name).

Hi, I'm not sure I understand what you want to do. In the event, you just incline to naming variables in a loop, bcs you are used to do it from other languages, pls note that in ML evth includes a reference in itself. It took me quite a moment to see it. So if you store your whatever stuff in a cell array or in a matrix, you simply can refer to elements or groups of elements in there (using a single or more dimension index).

x = {1.683434, 2.973835, 3.803803}
for ii = 1:3
thelabel{ii} = num2str(x{ii})
....
xlabel(thelabel{ii})
end

Otherwise, do you just need to get all values of x on the x axis in a string format?
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