MATLAB: The both results are different

symbolicSymbolic Math Toolbox

I compute the little program in matlab

clear; clf;
syms a b 
f1 = 96*pi - 16*pi * (log(a)-log(b)+1)
f1_ = subs(f1,[a b],[12 2])
f1_ = vpa(f1_)
f2 = 96*pi - 16*pi*(log(12)-log(2)+1)
with the output
f1 = 
   
f1_ = 
   
f1_ = 
   
f2 = 161.2638

Why the results are different?

Best Answer

With the newest Update R2020a Update 2 the problem is solved. The new output is ok

f1 =

f1_ =

161.26375811875458240605931894947

f2 = 161.2638

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