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authorJason Downs <downsj@cvs.openbsd.org>1996-08-19 10:13:38 +0000
committerJason Downs <downsj@cvs.openbsd.org>1996-08-19 10:13:38 +0000
commit14856225739aa48b6c9cf4c17925362b2d95cea3 (patch)
treedfd38f1b654fb5bbdfc38887c1a829b658e71530 /gnu/usr.bin/perl/lib/bigint.pl
parent77469082517e44fe6ca347d9e8dc7dffd1583637 (diff)
Import of Perl 5.003 into the tree. Makefile.bsd-wrapper and
config.sh.OpenBSD are the only local changes.
Diffstat (limited to 'gnu/usr.bin/perl/lib/bigint.pl')
-rw-r--r--gnu/usr.bin/perl/lib/bigint.pl275
1 files changed, 275 insertions, 0 deletions
diff --git a/gnu/usr.bin/perl/lib/bigint.pl b/gnu/usr.bin/perl/lib/bigint.pl
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+++ b/gnu/usr.bin/perl/lib/bigint.pl
@@ -0,0 +1,275 @@
+package bigint;
+
+# arbitrary size integer math package
+#
+# by Mark Biggar
+#
+# Canonical Big integer value are strings of the form
+# /^[+-]\d+$/ with leading zeros suppressed
+# Input values to these routines may be strings of the form
+# /^\s*[+-]?[\d\s]+$/.
+# Examples:
+# '+0' canonical zero value
+# ' -123 123 123' canonical value '-123123123'
+# '1 23 456 7890' canonical value '+1234567890'
+# Output values always always in canonical form
+#
+# Actual math is done in an internal format consisting of an array
+# whose first element is the sign (/^[+-]$/) and whose remaining
+# elements are base 100000 digits with the least significant digit first.
+# The string 'NaN' is used to represent the result when input arguments
+# are not numbers, as well as the result of dividing by zero
+#
+# routines provided are:
+#
+# bneg(BINT) return BINT negation
+# babs(BINT) return BINT absolute value
+# bcmp(BINT,BINT) return CODE compare numbers (undef,<0,=0,>0)
+# badd(BINT,BINT) return BINT addition
+# bsub(BINT,BINT) return BINT subtraction
+# bmul(BINT,BINT) return BINT multiplication
+# bdiv(BINT,BINT) return (BINT,BINT) division (quo,rem) just quo if scalar
+# bmod(BINT,BINT) return BINT modulus
+# bgcd(BINT,BINT) return BINT greatest common divisor
+# bnorm(BINT) return BINT normalization
+#
+
+$zero = 0;
+
+
+# normalize string form of number. Strip leading zeros. Strip any
+# white space and add a sign, if missing.
+# Strings that are not numbers result the value 'NaN'.
+
+sub main'bnorm { #(num_str) return num_str
+ local($_) = @_;
+ s/\s+//g; # strip white space
+ if (s/^([+-]?)0*(\d+)$/$1$2/) { # test if number
+ substr($_,$[,0) = '+' unless $1; # Add missing sign
+ s/^-0/+0/;
+ $_;
+ } else {
+ 'NaN';
+ }
+}
+
+# Convert a number from string format to internal base 100000 format.
+# Assumes normalized value as input.
+sub internal { #(num_str) return int_num_array
+ local($d) = @_;
+ ($is,$il) = (substr($d,$[,1),length($d)-2);
+ substr($d,$[,1) = '';
+ ($is, reverse(unpack("a" . ($il%5+1) . ("a5" x ($il/5)), $d)));
+}
+
+# Convert a number from internal base 100000 format to string format.
+# This routine scribbles all over input array.
+sub external { #(int_num_array) return num_str
+ $es = shift;
+ grep($_ > 9999 || ($_ = substr('0000'.$_,-5)), @_); # zero pad
+ &'bnorm(join('', $es, reverse(@_))); # reverse concat and normalize
+}
+
+# Negate input value.
+sub main'bneg { #(num_str) return num_str
+ local($_) = &'bnorm(@_);
+ vec($_,0,8) ^= ord('+') ^ ord('-') unless $_ eq '+0';
+ s/^H/N/;
+ $_;
+}
+
+# Returns the absolute value of the input.
+sub main'babs { #(num_str) return num_str
+ &abs(&'bnorm(@_));
+}
+
+sub abs { # post-normalized abs for internal use
+ local($_) = @_;
+ s/^-/+/;
+ $_;
+}
+
+# Compares 2 values. Returns one of undef, <0, =0, >0. (suitable for sort)
+sub main'bcmp { #(num_str, num_str) return cond_code
+ local($x,$y) = (&'bnorm($_[$[]),&'bnorm($_[$[+1]));
+ if ($x eq 'NaN') {
+ undef;
+ } elsif ($y eq 'NaN') {
+ undef;
+ } else {
+ &cmp($x,$y);
+ }
+}
+
+sub cmp { # post-normalized compare for internal use
+ local($cx, $cy) = @_;
+ $cx cmp $cy
+ &&
+ (
+ ord($cy) <=> ord($cx)
+ ||
+ ($cx cmp ',') * (length($cy) <=> length($cx) || $cy cmp $cx)
+ );
+}
+
+sub main'badd { #(num_str, num_str) return num_str
+ local(*x, *y); ($x, $y) = (&'bnorm($_[$[]),&'bnorm($_[$[+1]));
+ if ($x eq 'NaN') {
+ 'NaN';
+ } elsif ($y eq 'NaN') {
+ 'NaN';
+ } else {
+ @x = &internal($x); # convert to internal form
+ @y = &internal($y);
+ local($sx, $sy) = (shift @x, shift @y); # get signs
+ if ($sx eq $sy) {
+ &external($sx, &add(*x, *y)); # if same sign add
+ } else {
+ ($x, $y) = (&abs($x),&abs($y)); # make abs
+ if (&cmp($y,$x) > 0) {
+ &external($sy, &sub(*y, *x));
+ } else {
+ &external($sx, &sub(*x, *y));
+ }
+ }
+ }
+}
+
+sub main'bsub { #(num_str, num_str) return num_str
+ &'badd($_[$[],&'bneg($_[$[+1]));
+}
+
+# GCD -- Euclids algorithm Knuth Vol 2 pg 296
+sub main'bgcd { #(num_str, num_str) return num_str
+ local($x,$y) = (&'bnorm($_[$[]),&'bnorm($_[$[+1]));
+ if ($x eq 'NaN' || $y eq 'NaN') {
+ 'NaN';
+ } else {
+ ($x, $y) = ($y,&'bmod($x,$y)) while $y ne '+0';
+ $x;
+ }
+}
+
+# routine to add two base 1e5 numbers
+# stolen from Knuth Vol 2 Algorithm A pg 231
+# there are separate routines to add and sub as per Kunth pg 233
+sub add { #(int_num_array, int_num_array) return int_num_array
+ local(*x, *y) = @_;
+ $car = 0;
+ for $x (@x) {
+ last unless @y || $car;
+ $x -= 1e5 if $car = (($x += shift(@y) + $car) >= 1e5);
+ }
+ for $y (@y) {
+ last unless $car;
+ $y -= 1e5 if $car = (($y += $car) >= 1e5);
+ }
+ (@x, @y, $car);
+}
+
+# subtract base 1e5 numbers -- stolen from Knuth Vol 2 pg 232, $x > $y
+sub sub { #(int_num_array, int_num_array) return int_num_array
+ local(*sx, *sy) = @_;
+ $bar = 0;
+ for $sx (@sx) {
+ last unless @y || $bar;
+ $sx += 1e5 if $bar = (($sx -= shift(@sy) + $bar) < 0);
+ }
+ @sx;
+}
+
+# multiply two numbers -- stolen from Knuth Vol 2 pg 233
+sub main'bmul { #(num_str, num_str) return num_str
+ local(*x, *y); ($x, $y) = (&'bnorm($_[$[]), &'bnorm($_[$[+1]));
+ if ($x eq 'NaN') {
+ 'NaN';
+ } elsif ($y eq 'NaN') {
+ 'NaN';
+ } else {
+ @x = &internal($x);
+ @y = &internal($y);
+ local($signr) = (shift @x ne shift @y) ? '-' : '+';
+ @prod = ();
+ for $x (@x) {
+ ($car, $cty) = (0, $[);
+ for $y (@y) {
+ $prod = $x * $y + $prod[$cty] + $car;
+ $prod[$cty++] =
+ $prod - ($car = int($prod * 1e-5)) * 1e5;
+ }
+ $prod[$cty] += $car if $car;
+ $x = shift @prod;
+ }
+ &external($signr, @x, @prod);
+ }
+}
+
+# modulus
+sub main'bmod { #(num_str, num_str) return num_str
+ (&'bdiv(@_))[$[+1];
+}
+
+sub main'bdiv { #(dividend: num_str, divisor: num_str) return num_str
+ local (*x, *y); ($x, $y) = (&'bnorm($_[$[]), &'bnorm($_[$[+1]));
+ return wantarray ? ('NaN','NaN') : 'NaN'
+ if ($x eq 'NaN' || $y eq 'NaN' || $y eq '+0');
+ return wantarray ? ('+0',$x) : '+0' if (&cmp(&abs($x),&abs($y)) < 0);
+ @x = &internal($x); @y = &internal($y);
+ $srem = $y[$[];
+ $sr = (shift @x ne shift @y) ? '-' : '+';
+ $car = $bar = $prd = 0;
+ if (($dd = int(1e5/($y[$#y]+1))) != 1) {
+ for $x (@x) {
+ $x = $x * $dd + $car;
+ $x -= ($car = int($x * 1e-5)) * 1e5;
+ }
+ push(@x, $car); $car = 0;
+ for $y (@y) {
+ $y = $y * $dd + $car;
+ $y -= ($car = int($y * 1e-5)) * 1e5;
+ }
+ }
+ else {
+ push(@x, 0);
+ }
+ @q = (); ($v2,$v1) = @y[-2,-1];
+ while ($#x > $#y) {
+ ($u2,$u1,$u0) = @x[-3..-1];
+ $q = (($u0 == $v1) ? 99999 : int(($u0*1e5+$u1)/$v1));
+ --$q while ($v2*$q > ($u0*1e5+$u1-$q*$v1)*1e5+$u2);
+ if ($q) {
+ ($car, $bar) = (0,0);
+ for ($y = $[, $x = $#x-$#y+$[-1; $y <= $#y; ++$y,++$x) {
+ $prd = $q * $y[$y] + $car;
+ $prd -= ($car = int($prd * 1e-5)) * 1e5;
+ $x[$x] += 1e5 if ($bar = (($x[$x] -= $prd + $bar) < 0));
+ }
+ if ($x[$#x] < $car + $bar) {
+ $car = 0; --$q;
+ for ($y = $[, $x = $#x-$#y+$[-1; $y <= $#y; ++$y,++$x) {
+ $x[$x] -= 1e5
+ if ($car = (($x[$x] += $y[$y] + $car) > 1e5));
+ }
+ }
+ }
+ pop(@x); unshift(@q, $q);
+ }
+ if (wantarray) {
+ @d = ();
+ if ($dd != 1) {
+ $car = 0;
+ for $x (reverse @x) {
+ $prd = $car * 1e5 + $x;
+ $car = $prd - ($tmp = int($prd / $dd)) * $dd;
+ unshift(@d, $tmp);
+ }
+ }
+ else {
+ @d = @x;
+ }
+ (&external($sr, @q), &external($srem, @d, $zero));
+ } else {
+ &external($sr, @q);
+ }
+}
+1;