Differences between version 2 and predecessor to the previous major change of perlfaq4(1).
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| Newer page: | version 2 | Last edited on Tuesday, June 4, 2002 12:22:33 am | by perry | Revert |
| Older page: | version 1 | Last edited on Tuesday, June 4, 2002 12:22:33 am | by perry | Revert |
@@ -61,9 +61,9 @@
This affects __all__ computer languages that represent
decimal floating-point numbers in binary, not just Perl.
Perl provides arbitrary-precision decimal numbers with the
-Math::BigFloat module (part of the standard Perl
+Math::!
BigFloat module (part of the standard Perl
distribution), but mathematical operations are consequently
slower.
@@ -195,9 +195,9 @@
__How do I multiply matrices?__
-Use the Math::Matrix or Math::MatrixReal modules (available
+Use the Math::Matrix or Math::!
MatrixReal modules (available
from CPAN ) or the PDL
extension (also available from CPAN
).
@@ -267,9 +267,9 @@
If you want numbers that are more random than rand
with srand provides, you should also check out the
-Math::TrulyRandom module from CPAN . It uses
+Math::!
TrulyRandom module from CPAN . It uses
the imperfections in your system's timer to generate random
numbers, but this takes quite a while. If you want a better
pseudorandom generator than comes with your operating
system, look at ``Numerical Recipes in C'' at
@@ -346,9 +346,9 @@
__How can I find the Julian Day?__
-Use the Time::JulianDay module (part of the Time-modules
+Use the Time::!
JulianDay module (part of the Time-modules
bundle available from CPAN .)
Before you immerse yourself too deeply in this, be sure to
@@ -517,9 +517,9 @@
If you are serious about writing a parser, there are a
number of modules or oddities that will make your life a lot
easier. There are the CPAN modules
-Parse::RecDescent, Parse::Yapp, and Text::Balanced; and the
+Parse::!
RecDescent, Parse::Yapp, and Text::Balanced; and the
byacc program.
One simple destructive, inside-out approach that you might
@@ -704,13 +704,13 @@
push(@new, $+) while $text =~ m{
If you want to represent quotation marks inside a quotation-mark-delimited field, escape them with backslashes (eg, . Unescaping them is a task addressed earlier in this section.
-Alternatively, the Text::ParseWords module (part of the
+Alternatively, the Text::!
ParseWords module (part of the
standard Perl distribution) lets you say:
- use Text::ParseWords;
+ use Text::!
ParseWords;
@new = quotewords(
There's also a Text::CSV (Comma-Separated Values) module on CPAN .
@@ -1166,18 +1166,18 @@
my ($first, $second) = @_;
no warnings; # silence spurious -w undef complaints
return 0 unless @$first == @$second;
for (my $i = 0; $i
-For multilevel structures, you may wish to use an approach more like this one. It uses the CPAN module FreezeThaw:
+For multilevel structures, you may wish to use an approach more like this one. It uses the CPAN module !
FreezeThaw:
- use FreezeThaw qw(cmpStr);
+ use !
FreezeThaw qw(cmpStr);
@a = @b = (
printf
This approach also works for comparing hashes. Here we'll demonstrate two different answers:
- use FreezeThaw qw(cmpStr cmpStrHard);
+ use !
FreezeThaw qw(cmpStr cmpStrHard);
%a = %b = (
printf
printf
The first reports that both those the hashes contain the same data, while the second reports that they do not. Which you prefer is left as an exercise to the reader.
@@ -1536,9 +1536,9 @@
You can look into using the DB_File module and ''tie()''
using the $DB_BTREE hash bindings as documented in
-``In Memory Databases'' in DB_File. The Tie::IxHash module
+``In Memory Databases'' in DB_File. The Tie::!
IxHash module
from CPAN might also be
instructive.
@@ -1698,13 +1698,13 @@
__How can I make my hash remember the order I put elements
into it?__
-Use the Tie::IxHash from CPAN .
+Use the Tie::!
IxHash from CPAN .
- use Tie::IxHash;
-tie(%myhash, Tie::IxHash);
+ use Tie::!
IxHash;
+tie(%myhash, Tie::!
IxHash);
for ($i=0; $i
__Why does passing a subroutine an undefined element in a
@@ -1804,9 +1804,9 @@
For some specific applications, you can use one of the
DBM modules. See AnyDBM_File. More
-generically, you should consult the FreezeThaw, Storable, or
+generically, you should consult the !
FreezeThaw, Storable, or
Class::Eroot modules from CPAN . Here's one
example using Storable's store and
retrieve functions:
@@ -1846,9 +1846,9 @@
__How do I verify a credit card checksum?__
-Get the Business::CreditCard module from CPAN
+Get the Business::!
CreditCard module from CPAN
.
__How do I pack arrays of doubles or floats for
