Symbolic evaluation with value

In a lecture I had my tutor showed us how to evalute a symbolic equation that he had made but with a value for the symbolic variable (just 1 symbolic variable in the equation), he then put it into a graph to display but the original equation was in symbolic form. Does anyone know what that function is as I can't find it for the life of me. It wasn't subs, also looking for this specific function as its relative to my current equation.

[Torsten]

To substitute numerical values for symbolic variables, use "subs".

To transform a symbolic function to a numeric function handle, use "MatlabFunction".

Answer 1

[Rishav]

Hi Bert,

• "subs" is used to substitute numerical values for symbolic variables.

Here is an example on how to use 'subs':

% Define a symbolic variable x
syms x;
% Define a symbolic equation
eq = x^3 + 4*x + 1; 

% Substitute a specific value for x
x_value = 2;
result = subs(eq, x, x_value);

% Display the result
disp(result);

• "matlabFunction" is used to transform a symbolic function to a numeric function handle.

Here is an example on how to use 'matlabFunction':

% Define symbolic variables
syms x y;

% Define a symbolic expression
f = x^2 + y^2;

% Create a numeric function handle
numeric_function = matlabFunction(f, 'Vars', [x, y]);

% Now you can use the numeric_function to evaluate the expression numerically
x_value = 3;
y_value = 4;
result = numeric_function(x_value, y_value);

% Display the result
disp(result);