Matlab wont shorten answer after format short

Question

I'm trying to get matlab to shorten the answer into scientific notation but it continues to display long numbers.

Here is my matlab script:

syms E;
kb=8.617e-5; %eV/k
h=4.136e-15; %eV*s
Ts=5760; %k
q=1; %ev
c=3.0e8; %m/s
theta_s=atan(7e8/1.5e11); %rad

format short
Il_per_area = (q*pi/2)*(1-cos(2*theta_s))*int(((2/h^3*c^2)*E^2)/(exp(E/(kb*Ts-1))),E)

This is the result matlab gave me:

Il_per_area =

(52508430427297951419542428146127404493579145286547868195529063488882991519987*exp((2251799813685248*E)/1134143295600563)*((5070602400912917605986812821504*E^2)/1286281014955706024710845916969 - (4503599627370496*E)/1134143295600563 + 2))/2361183241434822606848

Can someone help me.

Answer 1

That is how Matlab deals with symbolic expressions. You can either try substituting a value of E

subs(Il_per_area, 3.2)

or rather, you'd like to see shorter parameters in the answer with the symbolic E:

add one line of variable-precision arithmetic (VPA)

vpa(Il_per_area,4)

The answer is

ans =

2.223e55*exp(1.985*E)*(3.942*E^2 - 3.971*E + 2.0)