coefficients checked asking for him

I would like to check the coefficients of a quadratic equation as a real number. I would like to establish a vector for an equation ax^2+bx+c--> [a b c] . in case of the variable if you are a character writes zero let the felhaszáló ask for the number again with an error message.How I may make this?

Answer 1

[BhaTTa]

To create a MATLAB script that checks the coefficients of a quadratic equation and ensures they are real numbers and coeffecients are not equal to 0, you can use the following approach. The script will prompt the user to input the coefficients and will check if they are valid real numbers. If a user inputs a character or an invalid number, the script will display an error message and prompt the user to enter the number again.

Here’s a step-by-step script to achieve this:

% Function to prompt the user for a real number input
function coeff = getRealNumber(prompt)
    while true
        coeff = input(prompt, 's');  % Read input as a string
        num = str2double(coeff);     % Convert string to number
        if isnan(num) || num==0               % Check if the conversion was not successful
            disp('Error: Please enter a valid real number.');
        else
            coeff = num;             % Assign the valid number to coeff
            break;                   % Exit the loop if input is valid
        end
    end
end

% Main script to get the coefficients of the quadratic equation
disp('Enter the coefficients for the quadratic equation ax^2 + bx + c:');

a = getRealNumber('Enter coefficient a: ');
b = getRealNumber('Enter coefficient b: ');
c = getRealNumber('Enter coefficient c: ');

% Create the coefficients vector
coefficients = [a, b, c];

% Display the coefficients vector
disp('The coefficients vector is:');
disp(coefficients);

[Walter Roberson]

Close, but 0 should be a valid coefficient. For example the user might want to enter 1*x^2 + 0*x - 1 (in other words, x^2 - 1)

A result of 0 from str2double() does not indicate an error.

(It is true, though, that you might generally want to restrict the first coefficient to be non-zero.)