input equation from user

Hi, I am a new user for MATLAB and I have R2010a version. I want to write a program where user should be able to enter euqation as input. e.g. : 5x^2 + 2x =8. And once the equation is fed in, I want to find out value of the equation for a perticular x value.

Please help.

Answer 1

[Jos (10584)]

str = input('Give an equation in x: ','s')  ;
   % the user types in, for instance 2*x^2-3*x+4
x = input('Type in a value of x: ') ; 
   % the user types in, for instance, 2
f = inline(str,'x') ;
y = feval(f,x) ;
disp(['"' str '", for x = ' num2str(x) ', equals ' num2str(y)]) ;

This will error when the string cannot be converted to an inline function or when the function cannot be evaluated for the value entered by the user.

[Saumya]

Thank you Jos,

It was really helpful.

Now going one step ahead, how can I do the same for a function with 2 variables say x and y.

Answer 2

[Manjeet Singh]

str = input('Give an equation in x and y: ','s');  % the user types equation in form of x and y
f = inline(str,'x','y')   % This gives function in form of f(x,y) $ both value of x and y can be put like  f(2,3)

[Sourin Dey]

Can you kindly show me the way to read the coefficients from the input equation? (The equation will be taken using input function)

Answer 3

[Mohammed Alrajeb]

hi every one

i need to your help

i need to enter 4 input (decimal number) and convert to binary number 32bit how can do that?