C CLVECA    SOURCE    CHAT      05/01/12    22:08:58     5004           
      SUBROUTINE CLVECA (SIGMA,VECZ,ANGLE,IANGLE)                               
C                                                                               
      IMPLICIT INTEGER(I-N)
      IMPLICIT REAL*8(A-H,O-Z)                                                  
C                                                                               
      DIMENSION SIGMA(*),SIG(3),VECZ(*)                                         
C                                                                               
C INITIALISATION                                                                
C                                                                               
      UNIT=0.0174532925199432957692D0                                           
      SIG(1)=SIGMA(1)                                                           
      SIG(2)=SIGMA(2)                                                           
      SIG(3)=SIGMA(4)                                                           
C                                                                               
      IF(IANGLE.EQ.0) THEN                                                      
        CALL VPMAX3 (SIGMA,SIGMAX,VECZ)                                         
        RETURN                                                                  
      ENDIF                                                                     
C                                                                               
      IF(IANGLE.GT.0) THEN                                                      
        CALL DIAGOD (SIG)                                                       
        ANGLE=SIG(3)                                                            
        IF(IANGLE.EQ.2) ANGLE=ANGLE*UNIT                                        
        RETURN                                                                  
      ENDIF                                                                     
C                                                                               
      END