SUBROUTINE FJACS(X,QR,LENQR,PIVOT) C INTEGER LENQR,N,PIVOT(N+2) C DOUBLE PRECISION QR(LENQR),X(N) C C Evaluate the N x N symmetric Jacobian matrix of F(X) at X, and return C the result in packed skyline storage format in QR. LENQR is the length C of QR, and PIVOT contains the indices of the diagonal elements of the C Jacobian matrix within QR. PIVOT(N+1) and PIVOT(N+2) are set by C subroutine FODE. C RETURN END