use strict;
use XML::Twig;

my $sel = 'title';
my $ign = 'title/name/fnm[@letter="a"]';
my $twig = XML::Twig->new(
ignore_elts => { "$ign" => 1},
twig_roots  => { "$sel" => 1},
pretty_print => 'indented'
);

$twig->parsefile('1.xml');

$twig->print;

##</code><code>##

<?xml version="1.0"?>
<titles>
<title id="1">testing<name><snm>Houston</snm>, <fnm letter="c">Carl</fnm></name><g>69</g><ppg>20.1</ppg><rpg>3.4</rpg><apg>2.8</apg><blk>14</blk></title>
<title id="2">testing<name><snm>Houston</snm>, <fnm letter="a">Allan</fnm></name><g>69</g><ppg>20.1</ppg><rpg>3.4</rpg><apg>2.8</apg><blk>14</blk></title>
<title id="3">testign
    <name>Houston
    <fnm j="b">Bob</fnm>
    <g>49</g>
	<title>
	testing the sub title in title
	</title>
	<title>
	this is pcdata in subtitle
		<title>
		second sub level
		</title>
	</title>
</name>
</title>
<test>
This is a test
</test>
</titles>

##</code><code>##

<?xml version="1.0"?>
<titles>
  <title id="1">testing<name><snm>Houston</snm>, <fnm letter="c">Carl</fnm></name><g>69</g><ppg>20.1</ppg><rpg>3.4</rpg><apg>2.8</apg><blk>14</blk></title>
  
  <title id="3">testign
    <name>Houston
    <fnm j="b">Beb</fnm><g>49</g><title>
	testing the sub title in title
	</title><title>
	this is pcdata in subtitle
		<title>
		second sub level
		</title></title></name></title>
</titles>

##</code><code>##

<?xml version="1.0"?>
<titles>
  <title id="1">testing<name><snm>Houston</snm>, <fnm letter="c">Carl</fnm></name><g>69</g><ppg>20.1</ppg><rpg>3.4</rpg><apg>2.8</apg><blk>14</blk></title>
  <title id="2">testing<name><snm>Houston</snm>, </name><g>69</g><ppg>20.1</ppg><rpg>3.4</rpg><apg>2.8</apg><blk>14</blk></title>
  <title id="3">testign
    <name>Houston
    <fnm j="b">Beb</fnm><g>49</g><title>
	testing the sub title in title
	</title><title>
	this is pcdata in subtitle
		<title>
		second sub level
		</title></title></name></title>
</titles>