Extended the device parameter notation to include offsets using

'+' and '-' in the same way that '*' is currently used for specifying
a parameter scaling.  The combination of a scale and offset for the
same parameter has not (yet) been implemented.

extract/ExtBasic.c

@@ -1662,6 +1662,10 @@ extOutputParameters(def, transList, outFile)
 				fprintf(outFile, " %c%c=%s*%g",
 					plist->pl_param[0], plist->pl_param[1],
 					plist->pl_name, plist->pl_scale);
+			    else if (plist->pl_offset != 0.0)
+				fprintf(outFile, " %c%c=%s%+g",
+					plist->pl_param[0], plist->pl_param[1],
+					plist->pl_name, plist->pl_offset);
 			    else
 				fprintf(outFile, " %c%c=%s", plist->pl_param[0],
 					plist->pl_param[1], plist->pl_name);
@@ -1672,6 +1676,10 @@ extOutputParameters(def, transList, outFile)
 				fprintf(outFile, " %c=%s*%g",
 					plist->pl_param[0],
 					plist->pl_name, plist->pl_scale);
+			    if (plist->pl_offset != 0.0)
+				fprintf(outFile, " %c=%s%+g",
+					plist->pl_param[0],
+					plist->pl_name, plist->pl_offset);
 			    else
 				fprintf(outFile, " %c=%s", plist->pl_param[0],
 					plist->pl_name);

extract/ExtTech.c

@@ -2364,7 +2364,7 @@ ExtTechLine(sectionName, argc, argv)
 	    subcktParams = NULL;
 	    while ((paramName = strchr(argv[argc - 1], '=')) != NULL)
 	    {
-		char *mult;
+		char *mult, *offset;
 
 		paramName++;
 		newParam = (ParamList *)mallocMagic(sizeof(ParamList));
@@ -2393,6 +2393,21 @@ ExtTechLine(sectionName, argc, argv)
 		else
 		    newParam->pl_scale = 1.0;
 
+		if ((offset = strchr(paramName, '+')) != NULL)
+		{
+		    *offset = '\0';
+		    offset++;
+		    newParam->pl_offset = atof(offset);
+		}
+		else if ((offset = strchr(paramName, '-')) != NULL)
+		{
+		    *offset = '\0';
+		    offset++;
+		    newParam->pl_offset = -atof(offset);
+		}
+		else
+		    newParam->pl_offset = 0.0;
+
 		newParam->pl_name = StrDup((char **)NULL, paramName);
 		newParam->pl_next = subcktParams;
 		subcktParams = newParam;

extract/extractInt.h

@@ -78,6 +78,7 @@ typedef struct pl
     char	 pl_param[2];	/* Default character for parameter */
     char	*pl_name;	/* Full name for parameter */
     double	 pl_scale;	/* Scaling of parameter, if specified */
+    double	 pl_offset;	/* Offset of parameter, if specified */
     struct pl	*pl_next;	/* Next parameter in list */
 } ParamList;