Compute the poloidal integral of 'integrand' and
return the results in 'res'.
integer, intent(in) :: nt1, ns
real(i2mex_r8), intent(in) :: the(nt1)
real(i2mex_r8), intent(in) :: integrand(nt1, ns)
real(i2mex_r8), intent(out) :: res(ns)
integer, intent(out) :: ier