# quadratic calculator to display error messages

1 view (last 30 days)
Mohamed Rashed on 8 Mar 2021
Answered: Monisha Nalluru on 11 Mar 2021
hello i am trying to make a quadratic calculater that shows an error message or N/A when non solvable values are put in this is what i have so far but it dosent seem to be working how can i mend this?
vala = app.a.Value;
valb = app.b.Value;
valc = app.c.Value;
z1 =(-valb +sqrt(valb^2-4*vala*valc))/(2*vala);
z2 =(-valb -sqrt(valb^2-4*vala*valc))/(2*vala);
if z1 is double scalar;
app.x1.Value =z1;
else app.x1.Value ='N/A';
if z2 is double scalar
app.x2.Value =z2;
else app.x2.Value ='N/A';

Monisha Nalluru on 11 Mar 2021
From my understanding,
you want to display values when the roots are real and N/A in case of complex roots.
You can check whether the value is real using isreal() function
As an example
if (isreal(z1) & isreal(z2))
app.x1.value = z1;
app.x2.value = z2;
else
app.x1.value = 'N/A';
app.x2.value = 'N/A';
end

R2020b

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