Hi, I'm trying to use the g77 program to compile multiple files: g77 -o make1 beta_est.f mat_mul.f dist.f dlam.f random.f run1.f set_up.f simdata.f theta_est.f wn_est.f functions.f iidwt.f matrix.f solve.f thiid.f gsolve.f And I get this error: beta_est.f: In subroutine `beta_est': beta_est.f:34: warning: CALL MATMUL(INVA,NPARM,NPARM,UU,NPARM,IONE,STEP,ER) What can I do? We haven't been able to resolve this one last error. Appreciate any help. Thanks, Usha