Error using integral (line 85) A and B must be floating-point scalars.

My code is:

b=10;a=3;q=0.1;

scdf = @(x) (1-(b./(x+b)).^a)./(1-(b./(10+b)).^a);

integral(@(x) (1+q).*(1-scdf(x)).^0.5,0,10);

psi = @(p) integral(@(x) (1-scdf(x)).^0.5,0,10)-p./(1+q)-integral(@(x) (1-scdf(x)).^0.5,0,3-p);

p=0:0.001:3;

plot(p,psi(p))

The error is:

Error using integral (line 85)

A and B must be floating-point scalars.

Error in ambiguity>@(p)integral(@(x)(1-scdf(x)).^0.5,0,10)-p./(1+q)-integral(@(x)(1-scdf(x)).^0.5,0,3-p)

Error in ambiguity (line 9)

plot(p,psi(p))

Any help is very appreciated! Thanks in advance.

Answer 1

[Ameer Hamza]

integral() function cannot accept a vector for its limits. So you cannot pass p as a vector. You will need to pass each value of p, one by one. For this, you can use arrayfun(). Try this code

b=10;a=3;q=0.1;
scdf = @(x) (1-(b./(x+b)).^a)./(1-(b./(10+b)).^a);
psi_ = @(p) integral(@(x) (1-scdf(x)).^0.5,0,10)-p./(1+q)-integral(@(x) (1-scdf(x)).^0.5,0,3-p);
psi = @(p) arrayfun(psi_, p);
p=0:0.001:3;
plot(p,psi(p))

[James_111]

Thank you so much!

[Ameer Hamza]

I am glad to be of help.