Switch does not work in GUI

While running my code through a GUI the SWITCH function does that detect the cases, or maybe it just jumps to the bottom otherwise every time.

contents = cellstr(get(S.element,'String'));
t1 = contents{get(S.element,'Value')};
t = char(t1);
contents = cellstr(get(S.mass,'String'));
u1 = contents{get(S.mass,'Value')};
u = char(u1);
contents = cellstr(get(S.volume,'String'));
v1 = contents{get(S.volume,'Value')};
v = char(v1);

global dens 

switch t 
    case strcmp(t,'Scandium')
        dens = 2.989;
    case strcmp(t,'Yttrium')
        dens = 4.469;
    case strcmp(t,'Selenium')
        dens = 4.809;
    case strcmp(t,'Krypton')
        dens = .003733;
    case strcmp(t,'Neodymium')
        dens = 7.007;
    case strcmp(t,'Antimony')
        dens = 6.685;
    case strcmp(t,'Astatine')
        dens = 7;
    otherwise
        dens = 8.55;
end

Every time it jumps to the other wise option of -- dens = 8.55.

Answer 1

[Walter Roberson]

You need to convert

switch t

to

switch true

because the value that you give in the "switch" is compared to the values of the "case" statements, and the values of the case statements are the result of the strcmp() and hence are true or false.

Alternately, leave it as "switch t" and remove the strcmp()

case 'Yttrium'

[Walter Roberson]

Consider this:

densities = struct('scandium', 2.989', 'yttrium', 4.469, 'selenium', 4.809);
tl = lower(t);
if isfield(densities,tl)
  dens = densities.(tl);
else
  error('not a known element')
end

Answer 2

[Image Analyst]

Try it like this:

switch lower(t) 
    case 'scandium'
        dens = 2.989;
    case 'yttrium'
        dens = 4.469;
    case 'selenium'
        dens = 4.809;
    case 'krypton'
        dens = .003733;
    case 'neodymium'
        dens = 7.007;
    case 'antimony'
        dens = 6.685;
    case 'astatine'
        dens = 7;
    otherwise
        dens = 8.55;
end

Answer 3

[Lawson Hoover]

Thank you for the help, I had forgotten that STRCMP returns a true or false. I made the adjustments to the code and now it works! Thanks again!