# how to make an anonymous function with more than 1 statement or equation?

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Alfandias Saurena on 17 Feb 2022
Answered: Walter Roberson on 17 Feb 2022
for exmple, i have 2 or more equation (a and d), with some variable defined (B and C).
B=2
C=4
a=Bx;
d=Cx^2;
then, i want to solve :
sqrt(a+d)
B=2;
C=4;
f=@(x) (a=B*x) (d=C*x^2) sqrt(a+b);
Unsupported use of the '=' operator. To compare values for equality, use '=='. To specify name-value arguments, check that name is a valid identifier with no surrounding quotes.
f(2)

Stephen23 on 17 Feb 2022
Using anonymous functions:
B=2;
C=4;
Fa = @(x) B.*x;
Fd = @(x) C.*x.^2;
Fh = @(x) sqrt(Fa(x)+Fd(x));
Fh(2)
ans = 4.4721
Using the symbolic toolbox:
syms x
a = B*x;
d = C*x^2;
s = sqrt(a+d)
s = double(subs(s,2))
ans = 4.4721
Alfandias Saurena on 17 Feb 2022
thanks @Stephen,, i apreciate it

Arif Hoq on 17 Feb 2022
Edited: Arif Hoq on 17 Feb 2022
B=2;
C=4;
f=@(x) B*x +C*x^2;
% d=@(x) C*x^2
sqrt(f(2))
ans = 4.4721

Walter Roberson on 17 Feb 2022
I suspect that you could do that with careful use of having the anonymous function invoke evalc() with a character vector that was a command line that used evalin('caller') to retrieve the parameter, and assingin('base') to save the variable, and then a series of assignin('base') and evalin('base') calls.
This would not be recommended even a little, but you did not ask for our recommendations, only for how to do that task using multiple statements inside an anonymous function.
The approaches shown by Stephen are much better. I would have to have a really good reason to use the approach I outlined above, at least for anything other than proving it could be done.