Using a programmed struct name as function argument or programming pressing "enter" in the command window

I am trying to use a struct as an argument for my function:

     [Output] = Function(InputString);

I have programmed the form of the "InputString", using

InputString = ['SomeText(' num2str(SomeNumber) ').SomeText.m' month 'd' day 't' time];

which returns a character array. When copying and pasting the result of "InputString" into the command window and pressing enter, the desired field of the struct is correctly read. However, with the code above, MATLAB only using the text of "InputString" as an input and not the desired struct that it represents.

How do I program copying the result of "InputString" and entering it in the command window, or is there a nicer solution?

[Walter Roberson]

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

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

http://matlab.wikia.com/wiki/FAQ#How_can_I_share_data_between_callback_functions_in_my_GUI.28s.29.3F

Answer 1

[Guillaume]

As per Walter's comment dynamic naming of variables is a bad idea. However, in you case, it's the fields of the structure that are dynamic so it's less of a problem.

The crux of your issue is that the list of argument to a function is not a string. It's the actual content of a variable, which is of course not what you're passing. When you copy/paste that string you've built at the command prompt, you're actually evaluating it. That's why it works. You could do the same in your code, evaluate the string but do not do that as there is a much better way:

output = Function(SomeText(SomeNumber).SomeText.(sprintf('m%dd%dt%d', month, day, time)))

I'm assuming month, day, time are integers here and using sprintf to build the field name instead of string concatenation, but the important bit is that the dynamic field name is given using (). See Generate field names from variables.

[Matthes Müller]

Perfect, thank you very much!