open4: int_0^1 Sqrt(x) dx, acc=0.001 eps=0.001
result=0.667438, tolerance=1.667e-003, calls=12
exact =0.666667, error    =7.714e-004, test passed :)

open4: int_0^1 1/Sqrt(x) dx, acc=0.001 eps=0.001
result=1.999516, tolerance=3.000e-003, calls=412
exact =2.000000, error    =4.839e-004, test passed :)

open4: int_0^1 4*Sqrt(1-x^2) dx, acc=1E-06 eps=0
result=3.1415926640321, tolerance=1.000e-006, calls=472
exact =3.14159265358979, error    =1.044e-008, test passed :)

open8av: int_0^1 4*Sqrt(1-x^2) dx, acc=1E-06 eps=0
result=3.14159264429694, tolerance=1.000e-006, calls=32
exact =3.14159265358979, error    =9.293e-009, test passed :)