From: Rafael Garcia-Suarez <rgarciasuarez@gmail.com>
Date: Sat, 20 Sep 2003 10:00:12 +0000 (+0000)
Subject: FAQ sync.
X-Git-Url: http://git.shadowcat.co.uk/gitweb/gitweb.cgi?a=commitdiff_plain;h=6f0efb172c82e82c39073291db2462e39dbe4104;p=p5sagit%2Fp5-mst-13.2.git

FAQ sync.

p4raw-id: //depot/perl@21289
---

diff --git a/pod/perlfaq4.pod b/pod/perlfaq4.pod
index 70af877..53c7d02 100644
--- a/pod/perlfaq4.pod
+++ b/pod/perlfaq4.pod
@@ -1,6 +1,6 @@
 =head1 NAME
 
-perlfaq4 - Data Manipulation ($Revision: 1.44 $, $Date: 2003/07/28 17:35:21 $)
+perlfaq4 - Data Manipulation ($Revision: 1.49 $, $Date: 2003/09/20 06:37:43 $)
 
 =head1 DESCRIPTION
 
@@ -120,7 +120,7 @@ Perl numbers whose absolute values are integers under 2**31 (on 32 bit
 machines) will work pretty much like mathematical integers.  Other numbers
 are not guaranteed.
 
-=head2 How do I convert between numeric representations?
+=head2 How do I convert between numeric representations/bases/radixes?
 
 As always with Perl there is more than one way to do it.  Below
 are a few examples of approaches to making common conversions
@@ -139,18 +139,15 @@ programmers the notation might be familiar.
 
 Using perl's built in conversion of 0x notation:
 
-    $int = 0xDEADBEEF;
-    $dec = sprintf("%d", $int);
+    $dec = 0xDEADBEEF;
 
 Using the hex function:
 
-    $int = hex("DEADBEEF");
-    $dec = sprintf("%d", $int);
+    $dec = hex("DEADBEEF");
 
 Using pack:
 
-    $int = unpack("N", pack("H8", substr("0" x 8 . "DEADBEEF", -8)));
-    $dec = sprintf("%d", $int);
+    $dec = unpack("N", pack("H8", substr("0" x 8 . "DEADBEEF", -8)));
 
 Using the CPAN module Bit::Vector:
 
@@ -162,13 +159,14 @@ Using the CPAN module Bit::Vector:
 
 Using sprintf:
 
-    $hex = sprintf("%X", 3735928559);
+    $hex = sprintf("%X", 3735928559); # upper case A-F
+    $hex = sprintf("%x", 3735928559); # lower case a-f
 
-Using unpack
+Using unpack:
 
     $hex = unpack("H*", pack("N", 3735928559));
 
-Using Bit::Vector
+Using Bit::Vector:
 
     use Bit::Vector;
     $vec = Bit::Vector->new_Dec(32, -559038737);
@@ -185,13 +183,11 @@ And Bit::Vector supports odd bit counts:
 
 Using Perl's built in conversion of numbers with leading zeros:
 
-    $int = 033653337357; # note the leading 0!
-    $dec = sprintf("%d", $int);
+    $dec = 033653337357; # note the leading 0!
 
 Using the oct function:
 
-    $int = oct("33653337357");
-    $dec = sprintf("%d", $int);
+    $dec = oct("33653337357");
 
 Using Bit::Vector:
 
@@ -206,7 +202,7 @@ Using sprintf:
 
     $oct = sprintf("%o", 3735928559);
 
-Using Bit::Vector
+Using Bit::Vector:
 
     use Bit::Vector;
     $vec = Bit::Vector->new_Dec(32, -559038737);
@@ -217,13 +213,18 @@ Using Bit::Vector
 Perl 5.6 lets you write binary numbers directly with
 the 0b notation:
 
-	$number = 0b10110110;
+    $number = 0b10110110;
+
+Using oct:
+
+    my $input = "10110110";
+    $decimal = oct( "0b$input" );
 
-Using pack and ord
+Using pack and ord:
 
     $decimal = ord(pack('B8', '10110110'));
 
-Using pack and unpack for larger strings
+Using pack and unpack for larger strings:
 
     $int = unpack("N", pack("B32",
 	substr("0" x 32 . "11110101011011011111011101111", -32)));