Two improvements: (1) Command extension "ext2spice lvs" sets up

all the settings normally used for LVS (hierarchy on, cthresh
infinite, subcircuit top auto, etc.).  (2) Extract and extract
unique ignore cells marked as abstract views (property LEFview
is set) when checking for unconnected nets with the same name
label.

ext2spice/ext2spice.c

@@ -211,7 +211,8 @@ Exttospice_Init(interp)
 #define EXTTOSPC_BLACKBOX	11
 #define EXTTOSPC_RENUMBER	12
 #define EXTTOSPC_MERGENAMES	13
-#define EXTTOSPC_HELP		14
+#define EXTTOSPC_LVS		14
+#define EXTTOSPC_HELP		15
 
 void
 CmdExtToSpice(w, cmd)
@@ -262,6 +263,7 @@ CmdExtToSpice(w, cmd)
 	"renumber [on|off]	on = number instances X1, X2, etc.\n"
 	"			off = keep instance ID names",
 	"global [on|off]	on = merge unconnected global nets by name",
+	"lvs    		apply typical default settings for LVS",
 	"help			print help information",
 	NULL
     };
@@ -418,6 +420,27 @@ CmdExtToSpice(w, cmd)
 		esMergeNames = FALSE;
 	    break;
 
+	case EXTTOSPC_LVS:
+	    /* Apply default command settings for LVS */
+	    /* hierarchy = on		*/
+	    /* format    = ngspice	*/
+	    /* cthresh   = infinite	*/
+	    /* rthresh   = infinite	*/
+	    /* renumber  = off		*/
+	    /* scale     = off		*/
+	    /* blackbox  = on		*/
+	    /* subcircuit top = auto	*/
+
+	    esDoHierarchy = TRUE;
+	    esFormat = NGSPICE;
+	    LocCapThreshold = (EFCapValue)INFINITE_THRESHOLD_F;
+	    LocResistThreshold = INFINITE_THRESHOLD;
+	    esDoRenumber = FALSE;
+	    esScale = 0.0;
+	    esDoBlackBox = TRUE;
+	    esDoSubckt = 2;
+	    break;
+
 	case EXTTOSPC_SUBCIRCUITS:
 	    if (cmd->tx_argc == 2)
 	    {
@@ -489,7 +512,7 @@ CmdExtToSpice(w, cmd)
 	    if (idx < 0)
 	    {
 		Tcl_SetResult(magicinterp, "Bad format type.  Formats are:"
-			"spice2, spice3, and hspice.", NULL);
+			"spice2, spice3, hspice, and ngspice.", NULL);
 		return;
 	    }
 	    else