Unit conversion using switch case or else if functions

Im supposed to use the switch case method or the else if method to solve this question. Anyone has any ideas on how to solve this?

[dpb]

More important are your ideas...make a start and show us what you've done so far and then ask a specific question if/when you get stuck.

[Renato SL]

I think the documentation for the if then else (here) and switch case (here) are clear enough with the given examples there.

Have you tried anything yet?

[Melvinder Singh]

I've managed to come up with this. Ignore the attempt at humor in the code. Is there any easier way to about doing this?

%%%%%%%%%%QUESTION 1%%%%%%%%%%%%
fprintf('Greetings Prof. Wean Sin,\n')
fprintf('Program will ask u to imput a value first followed by units.\n')
fprintf('Please enter units as L, m3, ft3 or gal.\n')
fprintf('Final value will be rounded off to the nearest 2 decimal places.\n')
L=input('Enter the amount of volume:\n');
x=input('Enter your current unit:\n','s');
z=input('Enter your desired unit:\n','s') ;
switch x     %switching current unit and converting to L
    case 'L'
        L=L;
    case 'm3'
        L=L*1000;
    case 'ft3'
        L=L*28.3168;
    case 'gal'
        L=L*3.78541;
    otherwise 
        fprintf('unit is invalid. sad face.\n'); 
end 

switch z     %now converting it to desired vol. unit
    case 'L'
        L=L; 
    case 'm3'
        L=L/1000; 
    case 'ft3'
        L=L/28.3168;
    case 'gal'
        L=L/3.78541;
    otherwise
        fprintf('unit is invalid. sad face.\n');
end

if L<0
    fprintf('error, value is invalid. sad face\n');
else
    fprintf('The volume is %.2f %s \n', L, z);
end

[Melvinder Singh]

Like to make it in such a way that I only need to input the starting value and unit together and not separately.

[Renato SL]

How about making a function (documentation here) instead?

With a function, you can declare every input in one line.

Answer 1

[Srivardhan Gadila]

For "Like to make it in such a way that I only need to input the starting value and unit together and not separately" you can make use of strsplit, str2num functions as follows:

valuePlusUnit = "45.3245 ft3";
stringSplit = strsplit(valuePlusUnit);
value = str2num(stringSplit(1))
units = stringSplit(2)