How to write if else program on matlab?

This is the program, but it is not working. My output is always 5. But why? How to correct it? It is written as a matlab function in simulink.

PROGRAM:

function betaref = fcn(w)
if (w<5)
    betaref=45;
elseif (5<w<15)
    betaref=5;
elseif (15<w<25)
    betaref=0;
else
    betaref=90;
end

[Ameer Hamza]

Run

value = fcn(0);

It returns 45 on my system,

[Drishya Dinesh]

Thankyou for your reply!

This is my simulink diagram. My output should track betaref. My input is 25 which implies betaref should be zero. But i have 5 instead.

Answer 1

[Steven Lord]

elseif (0<power<=1000)

This doesn't do what you think it does. If you're writing this code in the MATLAB Editor and you're using a relatively recent release you should have received a Code Analyzer warning alerting you to that fact (an orange line in the right scroll bar for the Editor window and orange underlines of part of this construct.)

Instead:

    elseif (0<power & power<=1000)

[Drishya Dinesh]

Thankyou for your reply!

What if my program is like,

function betaref = fcn(w)

if (w<5)

betaref=45;

elseif (5<w<15)

betaref=5;

elseif (15<w<25)

betaref=0;

else

betaref=90;

end