string from a textbox

hi. i want to extract 4,5,6,5 from string 4x^3 + 5x^2 + 6x^1 + 5

Answer 1

[Paolo]

 str = '4x^3 + 5x^2 + 6x^1 + 5'
 num = regexp(str,'(?<!\^)(\d)','match');

[abdullah ek]

i also want to extract the missing cofficients i am using the function sym2pol like syms x c = sym2poly(x^3 - 2*x - 5); but i dont know how to convert my value from textbox into symbolic polynomial which can be placed in sym2poly function.

[Paolo]

What missing coefficients? I don't see any for the equation you shared. Perhaps you need to use str2sym to convert the string to a symbolic expression before you can use sym2pol or coeffs as suggested by Stephen. I am unable to test it for you because of this bug.

Answer 2

[Stephen23]

If you are using symbolic toolbox then you could use the appropriate function:

https://www.mathworks.com/help/symbolic/coeffs.html