Switch results at certain condition

g=9.81; %gravity acceleration
v=input('Enter the value of Velocity');
theta=30*pi/180;
% compute and display results
disp('time of flight(s):')
time_ground=2*v*sin(theta)/g;
disp('distance travelled(m):')
distance_traveled=v*cos(theta)*time_ground;
if distance_traveled >=10
    disp('Passed')
else
    disp('Failed')
end
if distance_traveled>=10;
grade=A;
switch(grade)
    case distance_traveled>10
        fprintf('B')
    case distance_traveled>15
        fprintf('A')
end

I want to make the grade change at certain condition. For example, if the distance traveled is more than 10, then the grade is B. When the distance traveled is more than 15, the grade is A. Please correct what am i doing wrong here. If possible, i dont want to get rid of the switch command. Thanks in advance.

Answer 1

[Steven Lord]

switch is not the right tool for this job. Use if instead.

switch is intended when you intend to distinguish between a fixed discrete set of possibilities.

pet = 'dog';
switch pet
    case 'cat'
        disp('meow')
    case 'parrot'
        disp('squawk')
    case 'dog'
        disp('bark')
    otherwise
        error('I don''t know what sound this type of pet makes')
end

bark

if is intended for when you have one or more criteria you want to check.

p = pi;
if p < 1
    disp('less than 1')
elseif p < 2
    disp('less than 2')
elseif p < 3
    disp('less than 3')
else
    disp('not less than 3')
end

not less than 3

[Amril Luqman]

Thank you, but after doing research by myself, it appear i can use these:

switch true
    case (distance_traveled>10 && distance_traveled<=20)
        disp('Grade C')
    case (distance_traveled>20 && distance_traveled<=30)
        disp('Grade B')
    case (distance_traveled>=30)
        disp('Grade A')

It works just like what i intented.