Bessel function based equation returns NaN as output. Kindly check where I went wrong.

I have attached the equation in image format and given the code below. Kindly help me find in which function i did mistake- bessel or sinh or exp.

EQUATION:

.

CODE:

I1=@(x) besselj(1,x.*sqrt(i/j)).*besselj(1,x.*sqrt(j/i)).*besselj(0,x.*(s/(sqrt(i.*j)))).*((sinh(x.*(aw/i).*sqrt(i/j)))/(x.*(aw/i).*sqrt(i/j))).*((sinh(x.*(aw/j).*sqrt(j/i)))/(x.*(aw/j).*sqrt(j/i))).*(exp(-x.*(z/(sqrt(i.*j)))))

I=integral(I1,0,Inf)

M=pi*u*n1*n2*sqrt(i*j)*I

OUTPUT:

NaN

[David Goodmanson]

Hi Swathi,

this is almost certainly happening because sinh(z)/z = 1 at z=0, but sinh(z) and z when calculated separately and divided, gives 0/0 =nan. You need to create a function that calculates sinh(z)/z and replaces nan by 1 at z=0.

Incidentally you are missing dots at a couple of locations:

((sinh(x.*(aw/i).*sqrt(i/j)))./(x.*(aw/i).*sqrt(i/j)))
                             ^

and similarly for the other sinh function. Of course this doesn't get you out of the nan problem, it just fixes up the element by element division.

[Swathi S]

Thank you David for your help. I will try this.