precision(0)
bitprecision(0)
precision(I,3)
default(realprecision,38);
t=(precision(1.,77)*x+1);
precision(t)
localprec(57);precision(1.)
localbitprec(128);bitprecision(1.)
bitprecision(1 + O(x), 10)
bitprecision(1 + O(3^5), 10)
bitprecision(1, 10)
precision(1./t)
precision(Qfb(1,0,-2));

serprec(1,x)
serprec(x+O(x^3),x)
serprec(x+O(x^3),y)
serprec((1+O(y^2))*x+y + O(y^3), y)

padicprec(0,2)
padicprec(0,"")
padicprec(1,2)  == padicprec(0,2)
padicprec(1/2,2)== padicprec(0,2)
padicprec(Mod(1,9),3)
padicprec(O(2^2),3)
padicprec(O(2^2),2)
t=1+O(2^3);
padicprec(t,2)
padicprec((x+2)*t, 2)
padicprec((1+2*x+O(x^2))*t, 2)
padicprec([2,4]*t, 2)
