Merge pull request #248 from PrincetonUniversity/nn-error

Add warning for nn == 0

Author: logan-nc

dcon/dcon.F

@@ -115,6 +115,12 @@ PROGRAM dcon
 #endif
       delta_mhigh=delta_mhigh*2
       use_classic_splines_for_dcon = use_classic_splines
+      
+      IF(nn .EQ. 0)THEN
+         WRITE(*,*)"ERROR: nn must be set to a positive integer."
+         CALL program_stop("nn must be a positive integer.")
+      ENDIF
+
 c-----------------------------------------------------------------------
 c     open output files, read, process, and diagnose equilibrium.
 c-----------------------------------------------------------------------