Ndim_ := 4: x1_ := t: x2_ := r: x3_ := theta: x4_ := phi: sig_ := 2: complex_ := {}: eta11_ := -1: eta22_ := 1: eta33_ := 1: eta44_ := 1: bd11_ := exp(1/2*A1(r)): bd22_ := exp(1/2*B1(r)): bd33_ := exp(1/2*B1(r))*r: bd44_ := exp(1/2*B1(r))*r*sin(theta): constraint_ := [A1(r) = int(2*epsilon*(-x*diff(z(x),x))^(1/2)/(1-z(x)*x^2),x = 0 .. r), B1(r) = int(-2*(epsilon*(-x*diff(z(x),x))^(1/2)-2*x*z(x))/(1-z(x)*x^2),x = 0 .. r),epsilon^2=1]: