How to stop a future modification in matlab sym function
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Hi all,
I have been using the symbolic toolbox for a while. I needed to create a symbolic function for an expected value. As matlab does not, at least for now, allow defining properties of arbitrary functions such as:
E(a+b)=E(a)+E(b)
or
E(k*eps)=k*E(eps)
(nor it allows defining variables and constants separately)
I've decided to go and transform my symbolic variable into char, use regular expressions, and then bring it back to symbolic. As I was doing so (the whole process works pretty well), as I ran the code:
result_symbolic=sym(result_char)
I received the following message:
"Warning: Support of character vectors that are not valid variable names or define a number will be removed in a future release. To create symbolic expressions, first create symbolic variables and then use operations on them. "
How can I make them know that there are cases in which it is not possible to actually manually create symbolic, like in the cases there I have worked on?
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Walter Roberson
2018년 2월 10일
You create a Technical Support case and present your use case.
... Probably they will refer you to the new str2sym() function.
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Walter Roberson
2018년 2월 10일
str2sym() was introduced in R2017b.
What you are doing will continue to work in R2017a and R2017b, but after that will likely fail.
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