How to substitute to a variable in a function with a constant

I'm trying to substitute some values of t to this equation:

x = 3.0 + 4.0.*t + c.*t.^2 - 2.0.*t.^3;

Unrecognized function or variable 't'.

But it won't work because of the c. The assignment is to avoid using symbolic math, how can I bypass this error? Like it would simply substitute the values of t with c remaining undefined. Thanks

[Stephen23]

Original question retrieved from Google Cache:

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How to substitute to a variable in a function with a constant

I'm trying to substitute some values of t to this equation:

x = 3.0 + 4.0.*t + c.*t.^2 - 2.0.*t.^3;

Unrecognized function or variable 't'.

But it won't work because of the c. The assignment is to avoid using symbolic math, how can I bypass this error? Like it would simply substitute the values of t with c remaining undefined. Thanks

Answer 1

[Chunru]

% Specify the values beforehand
t = 0:.1:5;
c = 2; 
x = 3.0 + 4.0.*t + c.*t.^2 - 2.0.*t.^3;
plot(t, x)

% symbolic computation
syms t c x
x = 3.0 + 4.0.*t + c.*t.^2 - 2.0.*t.^3

x = 

[ijsonvjksrefdsb]

c can't be defined...

[Chunru]

Do you want to have symbolic computation?