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	subroutine quatB(p1,p,p2,q)
c  convert Bunge Euler angles (radians) to quaternion; 
c  direct conversion from angles, see Altmann's book
c  the rotation is a vector transformation (active rotation)
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	real p1,p,p2,q(4)
	double precision c1,c,c2,s1,s,s2,d(3,3),tmp(4),sin2,cos2,rtmp,rnorm
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       PI=3.14159265
c  form cosine, sine of Phi, and sum & diff of phi1, phi2
       S=DSIN(0.5d0*P)
       C=DCOS(0.5d0*P)
       S1=DSIN(0.5d0*(P1-P2))
       C1=DCOS(0.5d0*(P1-P2))
       S2=DSIN(0.5d0*(P1+P2))
       C2=Dcos(0.5d0*(P1+P2))
c      write(*,*) 's1,c1,s,c,s2,c2'
c      write(*,*) s1,c1
c      write(*,*) s,c
c      write(*,*) s2,c2
	q(1)=s*c1
	q(2)=s*s1
	q(3)=c*s2
	q(4)=c*c2
	return
	end
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