[GRASS-CVS] hamish: grass6/raster/r.report prt_report.c,2.5,2.6

[grass at intevation.de]

Author: hamish

Update of /grassrepository/grass6/raster/r.report
In directory doto:/tmp/cvs-serv28613

Modified Files:
	prt_report.c 
Log Message:
more exact values.

the "units" program was calculating sq-m->acres using US survey feet
for some unknown reason!?


Index: prt_report.c
===================================================================
RCS file: /grassrepository/grass6/raster/r.report/prt_report.c,v
retrieving revision 2.5
retrieving revision 2.6
diff -u -d -r2.5 -r2.6
--- prt_report.c	16 Nov 2007 04:57:34 -0000	2.5
+++ prt_report.c	16 Nov 2007 08:51:37 -0000	2.6
@@ -63,7 +63,7 @@
 	case ACRES:
 	    unit[i].label[0] = "";
 	    unit[i].label[1] = "acres";
-	    unit[i].factor   = 2.4710439e-4;
+	    unit[i].factor   = 2.47105381467165e-4;  /* 640 acres in a sq mile */
 	    break;
 
 	case HECTARES:
@@ -75,7 +75,7 @@
 	case SQ_MILES:
 	    unit[i].label[0] = "square";
 	    unit[i].label[1] = " miles";
-	    unit[i].factor   = 3.8610216e-7;
+	    unit[i].factor   = 3.86102158542446e-7;  /* 1 / ( (0.0254m/in * 12in/ft * 5280ft/mi)^2 ) */
 	    break;
 
 	default: