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subroutine jvtaxx(ga,tc,g,xm1,xw,jw)
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c This subroutine computes the off-shell vector current
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c in terms of the vector w1 and tensor jt
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c complex ga : incoming vector boson
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c complex tc : incoming tensor particle
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c real g : coupling constant
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c complex jw : outgoing vector current
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c dimension of the current set to arbitrary length
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include "dimension.inc"
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double complex ga(DIM),jw(DIM),tc(DIM)
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double complex gt1(4), gt2(4)
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double precision q(0:3),g,q2,dv
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double precision xm1,xw
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double precision sqrTwo
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parameter( sqrTwo = 1.41421356237309514547462185873882845044d0 )
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jw(5) = ga(5) + tc(17)
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jw(6) = ga(6) + tc(18)
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q2 = q(0)**2 -q(1)**2 -q(2)**2 -q(3)**2
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c First take the inner product of the incoming vector with the
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c second index of the tensor
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gt2(1) = ga(1)*tc( 1) - ga(2)*tc( 2) - ga(3)*tc( 3) - ga(4)*tc( 4)
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gt2(2) = ga(1)*tc( 5) - ga(2)*tc( 6) - ga(3)*tc( 7) - ga(4)*tc( 8)
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gt2(3) = ga(1)*tc( 9) - ga(2)*tc(10) - ga(3)*tc(11) - ga(4)*tc(12)
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gt2(4) = ga(1)*tc(13) - ga(2)*tc(14) - ga(3)*tc(15) - ga(4)*tc(16)
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c and with the first index of the tensor
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gt1(1) = ga(1)*tc( 1) - ga(2)*tc( 5) - ga(3)*tc( 9) - ga(4)*tc(13)
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gt1(2) = ga(1)*tc( 2) - ga(2)*tc( 6) - ga(3)*tc(10) - ga(4)*tc(14)
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gt1(3) = ga(1)*tc( 3) - ga(2)*tc( 7) - ga(3)*tc(11) - ga(4)*tc(15)
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gt1(4) = ga(1)*tc( 4) - ga(2)*tc( 8) - ga(3)*tc(12) - ga(4)*tc(16)
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c The current is the difference of gt1 and gt2 with the remaining
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c tensor indices the indices of the outgoing vector current
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jw(1) = dv * (gt1(1) - gt2(1))
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jw(2) = dv * (gt1(2) - gt2(2))
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jw(3) = dv * (gt1(3) - gt2(3))
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jw(4) = dv * (gt1(4) - gt2(4))