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How do I assign a symbolic variable only to change the variable to an array?

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Hi, I am having a hard time trying to assign a symbolic variable to the input x. I am wanting to use x later in my code in its symbolic form but at exp1 I would like to assign the variable a value of an array. Any help is greatly appreciated.
% code
%Prompting for Amplitude and Limits of Interest
prompt = {'Enter the Value, "A", from the form A*exp(t). Include Negative Sign if Applicable',...
'Enter the Numerical Lower Limit Over Which to Plot the Function Segment'...
'Enter the Numerical Upper Limit Over Which to Plot the Function Segment'};
prompttitle = 'Information Input';
defaultans = {'1', '0', '4'};
answer = inputdlg(prompt, prompttitle, 1, defaultans);
expamp2 = str2double(answer(1,1));
explow1 = str2double(answer(2,1));
exphigh1 = str2double(answer(3,1));
%Defining Lower and Upper Limits Chosen in Each Iteration
lowerlimit1 = explow1;
upperlimit1 = exphigh1;
Syms t
%Decay Constant Prompt
prompt1 = 'Enter the Decay Constant Using the variable "/*t" and Include Positive or Negative Integers : ';
%Prompt User to input the decay constant. This was left as a
%command window input so that maximum variations can be inputted.
x = input(prompt1);
%Auto-Defining 'To' Based on Limit Selection
To = abs(exphigh1 - explow1);
Tolong = To*100;
%Defining Horizontal Axis
t = (explow1:.01:exphigh1);
%Formatting all variable to final exp form.
exp1=expamp2*exp(x);
%Generalizing naming convention for subplots
amplitude1 = exp1;
t1 = t;
clc
  1 Commento
Eric Cheatwood
Eric Cheatwood il 23 Ott 2017
In other words, I would like exp1 to perform calculations on the array of numbers t but I would like x to hold onto the symbolic value of t to be put through a Fourier Series later on. Thanks

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Risposta accettata

Walter Roberson
Walter Roberson il 23 Ott 2017
Something like,
syms x
X = input(prompt1);
exp1 = subs(expamp2 * exp(x), x, X);
  5 Commenti
Eric Cheatwood
Eric Cheatwood il 24 Ott 2017
I understand what you are saying. I defined t1 as a 'double' array. x equals some symbolic equation such as '-2*t' so the t is replaced with an array t1 using the subs function to make X but the symbolic equation x can still be used later. I suppose I could equally do the job with subs(x,t,t1) Thanks again.
Walter Roberson
Walter Roberson il 24 Ott 2017
Yes, it is clearer if the variable being substituted for is specified; I myself got confused when I made the above remark.

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