converting specific characters to a variable

Hi I have a string which look like this "x1 + x2+ 2.0e-14". I want to convert x1 and x2 to variables and use further. In addition I also want to convert the "2.0e-14" as a number. I have plenty of such variables. Is there any script which can recognize characters starting with "x" are variables and rest of them are numbers.

Answer 1

[Azzi Abdelmalek]

http://matlab.wikia.com/wiki/FAQ#How_can_I_create_variables_A1.2C_A2.2C....2CA10_in_a_loop.3F

Answer 2

[Star Strider]

You will need the Symbolic Math Toolbox to do what you want.