split math expresion into tokens

[madskiba]

how to saparete this '5+85*5/-1-106^0.15'.

and the result
'5' , '+' , '85' , '*' , '5' , '/' , '-1' ,  '-' , '106' , '^' , '0.15'

[Phil]

how to saparete this '5+85*5/-1-106^0.15'.

and the result
'5' , '+' , '85' , '*' , '5' , '/' , '-1' ,  '-' , '106' , '^' , '0.15'

If you need to parse the expression in order to evaluate it, try this:

http://wiki.lazarus.freepascal.org/How_To_Use_TFPExpressionParser

[Leledumbo]

The proper way is to build a parser, first part of Prof. Wirth book should help, but it's geared more toward in-class use. Otherwise Jack Crenshaw's articles is more practical, but is not really structured. Last but not least, if you think proper parsing is too complex to understand, you can always fallback to System.Copy, System.Delete, System.Pos, etc. but for me it's too cumbersome compared to time spent to understand parsing properly (it's also future proof for your skill).

[marcov]

Unit symbolic (that comes with Free Pascal) contains an expression evaluator. The tokenizer can return a tree form, or reduce that to RPN. (but that is string form again).

[Thaddy]

There's also the TParser class that can be used to do that. I once wrote a solver for simple math operations using that for an intermediate pascal course.
I'll see if I can find it. (Borland used the same example based on mine at the time, so maybe it is still available on the Embarcadero website?)).
It also depends on what OP wants: if he is a computer science student I would go for lex/yacc or Bison or Goldparser and use a parser generator.
Otherwise I would use TParser, but Marco's code is also fine.