1 files changed, 35 insertions, 0 deletions
diff --git a/sys/fmtio/dtcscl.x b/sys/fmtio/dtcscl.x
new file mode 100644
index 00000000..afd6adc5
--- /dev/null
+++ b/sys/fmtio/dtcscl.x
@@ -0,0 +1,35 @@
+# Copyright(c) 1986 Association of Universities for Research in Astronomy Inc.
+
+# DTCSCL -- Scales a double precision real, maintaining maximum precision.
+# Called by DTOC and CTOD.
+
+procedure dtcscl (v, e, sense)
+
+double	v		# value to be scaled
+int	e		# exponent
+int	sense		# sense of scaling (0=apply e to v;  1=calc e)
+
+begin
+	if (sense == 0) 		# scale v by 10 ** e
+	    v = v * (10.0d0 ** e)
+
+	else {				# scale number to 0.1 <= v < 1.0
+	    if (v == 0.0d0)
+		e = 0
+	    else {
+	        e = -1
+	        while (v < 0.1d0) {
+		    v = v * 10.0d0
+		    e = e - 1
+		    if (v == 0.0d0) {	# check for underflow to zero
+			e = 0
+			break
+		    }
+	        }
+	        while (v >= 1.0d0) {
+		    v = v / 10.0d0
+		    e = e + 1
+	        }
+	    }
+	}
+end