From fa080de7afc95aa1c19a6e6fc0e0708ced2eadc4 Mon Sep 17 00:00:00 2001 From: Joseph Hunkeler Date: Wed, 8 Jul 2015 20:46:52 -0400 Subject: Initial commit --- sys/fmtio/dtcscl.x | 35 +++++++++++++++++++++++++++++++++++ 1 file changed, 35 insertions(+) create mode 100644 sys/fmtio/dtcscl.x (limited to 'sys/fmtio/dtcscl.x') 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 -- cgit