What is wrong with my syntax here?

Question

The goal is to count the number of paragraphs in a group of users text...

(I will assume its always bigger than 5 paragraphs for this exercise)

Then I want to 1/2 the number of paragraphs, round it down and enter some content(echo "yehhoo") in between.

I do understand the way I have gotten my $newvalue is not very good, would also like help on that...

<?php

$choppedup = explode("<p>",$node->field_long_body[0]['safe']);
$choppedpos = count($choppedup);
$choppedpos2 = $choppedpos/2;
$newvalue = floor($choppedpos2);

//I know this is working to here... the rest not so sure.

for($j = 0; $j < $choppedup; $j ++):
  print $choppedup[$j];
  if ($j == $newvalue):
    echo "yehhoo" ;       
  endif;
endif;
?>

Thank you

Answer 1

for 
...
endfor;       # not endif

your $newvalue calculation is not terrible, for the array iteration I'd rather suggest foreach loop (using curly braces):

foreach($choppedup as $ind => $p) {
    echo $p;
    if ($ind == $newvalue) {
        echo 'yehoo';
    }
}

Answer 2

"Yehhoo" for curly brackets!

for($j == 0; $j < $choppedup; $j ++) {
     print $choppedup[$j];
     if ($j == $newvalue) {
          echo "yehhoo";
     }
}

Answer 3

Why do such a complex loop to count the number of paragraph tags?

You can do something like this:

 $sInput = '<p>Hello World</p><p>What is going on</p><p>Blah</p>';
 if(preg_match_all('/<p>/', $sInput, $arMatches)!==false)
  print count($arMatches[0]) . ' paragraphs<br/>';

Of course the above needs some work to make sure there are text between the paragraph tags, but this should work for you need.