java - How to check syntax error on algebraic expression -


i've been searching method check if algebraic expression written, find "how solve thing" or "how simplify mathematica".

you'll see, have program field input string, string should

"(x-a)^2-y+2"

, , have check if it's correct, if user inputs like:

  • ")x-4(+1"
  • "x*"
  • "4-9)6"
  • "+*--*7" ...etc, have it's wrong , try again. don't need result, or evaluate on x or anything, that. knows how this? appreciate help.

mathematica, wxmaxima, maple, etc. use syntax tree. define grammar , parse expression using grammar. furthermore type checking done.

one can generate java-parser using yacc or bison.


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