how to use anonymous function with equation without retype the all equation?
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Abdulaziz Abutunis
am 21 Mär. 2017
Kommentiert: Walter Roberson
am 21 Mär. 2017
Dear all,
does anyone know how to use the anonymous function with equation that already defined without type it again. For example,eq1 = x^2+3+y^3; sol=@(x,y) eq1. I tried eq1(2,2) but it does not work as wished. Please help
Best regards, Aziz
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Matt J
am 21 Mär. 2017
Bearbeitet: Matt J
am 21 Mär. 2017
If x, y and eq1 are symbolic variables, then there is no reason to be wrapping eq1 in an anonymous function. Just use the subs() command to evaluate eq1 at desired values. E.g.,
>> syms x y
>> eq1 = x^2+3+y^3
eq1 =
x^2 + y^3 + 3
>> val=double(subs(eq1,[x,y],[2,2]))
val =
15
If you insist on wrapping it in anonymous function, you could do something like,
sol=@(a,b) double(subs(eq1,[x,y],[a,b]))
1 Kommentar
Walter Roberson
am 21 Mär. 2017
If you are starting from symbolic expressions, then use matlabFunction() to create function handles for numeric processing.
Weitere Antworten (2)
Stephen23
am 21 Mär. 2017
Bearbeitet: Stephen23
am 21 Mär. 2017
>> sol = @(x,y)x^2+3+y^3;
>> sol(2,2)
ans =
15
exactly as the documentation shows:
3 Kommentare
James Tursa
am 21 Mär. 2017
Then please show us more detail about your problem. Where is the equation coming from? What is this iterative process doing? Etc.
Steven Lord
am 21 Mär. 2017
As written, eq1 is not an equation. x and y must be defined before you execute "eq1 = x^2+3+y^3;" or you will receive an error. If you want to define the equation once and use it later, execute:
sol = @(x,y) x.^2+3+y.^3;
Note I used .^ so you can call sol with a nonscalar array, not just a scalar. If you need eq1 to be the value of that function for specific values of x and y:
eq1 = sol(2, 2)
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