1 SUBROUTINE ksrot(U,UDOT,THETA)
7 IMPLICIT REAL*8 (a-h,o-z)
8 REAL*8 u(4),udot(4),uhat(4),v(4),vhat(4),uhat2(4),vhat2(4)
10 us = sqrt(u(1)**2 + u(2)**2 + u(3)**2 + u(4)**2)
14 udotr = udotr + udot(k)*uhat(k)
19 v(k) = udot(k) - udotr*uhat(k)
29 uhat2(k) = uhat(k)*cos(0.5d0*theta) + vhat(k)*sin(0.5d0*theta)
30 vhat2(k) = vhat(k)*cos(0.5d0*theta) - uhat(k)*sin(0.5d0*theta)
32 udot(k) = udotr*uhat2(k) + vs*vhat2(k)