how to combine symbolics and if statement?
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Karthik Nimishakavi
el 15 de Oct. de 2016
Editada: Karan Gill
el 17 de Oct. de 2017
Hello, My function is like this
y=x+2 for 0<=x<=10
y = x^2 for 10<x<=500 and x belongs to 0,500.
so I tried like this
syms x
if x>=0 && x<=10
y=x+2
else y=x^2
end
but i am getting an error saying
"Conversion to logical from sym is not possible"
"Operands to the || and && operators must be convertible to logical scalar values".
Please help me how to overcome this.
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Respuesta aceptada
Walter Roberson
el 15 de Oct. de 2016
You cannot use if together with symbolic expressions.
You should be considering using numeric expressions together with logical indexing. See though http://www.mathworks.com/matlabcentral/answers/301165-ode-suite-for-solving-switched-systems#comment_397941 for a discussion on hidden problems with one way of coding that.
You could also code the obscure
evalin(symengine, 'piecewise([0 <= x and x <= 10, x+2], [10 < x and x <= 500, x^2])')
but you will find that it probably will not be of any use to you.
Más respuestas (1)
Karan Gill
el 20 de Oct. de 2016
Editada: Karan Gill
el 17 de Oct. de 2017
In this case:
syms y(x)
y(x) = piecewise(0<=x<=10, x+2, 10<x<=500, x^2);
Now try
y(1)
ans =
3
>> y(12)
ans =
144
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