Why am I having so many errors?

The purpose of the code is to take the inputs and calculate the weight of something on a different planet. Here is the code:

    name = input('What is the name of the exoplanet? ', 's');
    massplanet = input( sprintf('What is the estimated mass of %s(kg)? ', name), 's');
    radius = input( sprintf('What is the estimated radius of %s(km)? ', name), 's');
    massspecimen = input('What is the mass of the specimen (kg)? ');

    %calculating acceleration due to gravity of other planet using:
    %G * mass / radius^2
    %G is a constant
    Accel_of_G_exo = ((6.67e-11) * massplanet) / radius^2 ;  

    %calculating weight of specimen using acceleration due to gravity of other
    %planet and mass of specimen
    Weight_exo = Accel_of_G_exo * massspecimen; 

    %trying to print the name of the planet as well as the variable Weight_exo
    fprintf('On %s, it would weigh about %f Newtons.',name, Weight_exo);

However, when I run the code, I am getting an error on the line where I try to define the variable 'Accel_of_G_exo'. I am assuming the variables 'massplanet' and 'radius' are stored as string types, therefore they can not be incorporated in an equation. Also, on the last line, I tried to print a statement that included the variables 'name' and 'Weight_exo', however, I do not think that I can use %s with fprintf. Thank you so much for the help. I am new to MATLAB and am still learning the program.

Answer 1

[Walter Roberson]

You need to str2double() the strings that hold the masses. Or just skip the 's' option of input() to read the values as numeric.

[Shawn Simon]

Thank you!

Answer 2

[Stalin Samuel]

      Accel_of_G_exo = ((6.67e-11) * massplanet) / radius.^2 ;   
      Weight_exo = Accel_of_G_exo * massspecimen ;   
      fprintf('On %s, it would weigh about %d Newtons.',name, Weight_exo);

[Shawn Simon]

When I ran this, it gave me an error on the Accel_of_G_exo line saying there was an error using '/'.

[Walter Roberson]

That would happen because your radius is a string, which in MATLAB is a vector of characters.