string to sym error

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Alberto Carlos
Alberto Carlos 2016-9-19
评论： Karan Gill 2016-10-25
I have the string
>> d='1/m'
>> class(d)
char
>> p=sym(d)
I get:
Warning: Support of strings that are not valid variable names or define a number will be removed in a future relase. To create symbolic expressions, firs create symbolic variables and then use operations on them.
after that p is empty
I tried syms m; at the beginning but i get the same error

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Mischa Kim
Mischa Kim 2016-9-19
Alberto, the functionality you are using will be removed in future releases, but you can still use it. That is why you are getting a warning message (not an error message).
Instead use,
syms m
p = 1/m
  2 个评论
Richard Wang
Richard Wang 2016-10-24
but if I do need to convert a string to symbolic expression, how can I realize it, since this sym() function will no longer in use?
For example, I want to type in an expression by keyboard input and I want to treat this expression as symbolic function or other.
Karan Gill
Karan Gill 2016-10-25
You can use "eval" on the string input.

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