matlab中极限的使用——Limit variable must be a symbolic variable.

syms I1 I2 I3 Q1 Q2 Q3

limit(acos((I2-I1)*(I3-I2)+(Q2-Q1)*(Q3-Q2)/(sqrt((I2-I1)^2+(Q2-Q1)^2)*sqrt((I3-I2)^2+(Q3-Q2)^2)))/(sqrt(I3-I1)^2+(Q3-Q1)^2),(sqrt(I3-I1)^2+(Q3-Q1)^2),inf)

[Dyuman Joshi]

You want to find the limit of the expression, but with respect to which variable?

Answer 1

[Arka]

Hi @晨曦,

You can go through the standard usage of the "limit" function from the MathWorks documentation link below:

https://www.mathworks.com/help/symbolic/limits.html

As can be seen from the link above, you need to calculate the limit of a function with respect to a symbolic variable. In your case, it is a symbolic expression, and not a symbolic variable.

Hope this helps!

[Dyuman Joshi]

OP already knows about limit, as they have used it in the code posted above.

Your answer does not add any extra info to this thread.

And it's not a function, but a symbolic expression.