map processes a list and returns a list, so you need to assign the list back to your @data array (or a new array). 

  @data = map { #? data is skiped when plotted
   if($maxreject[$i]) {
  $_ = "?$_" if($_ > $maxclip);
   }
   if($minreject[$i]) {
  $_ = "?$_" if($_ < $minclip);
   }
   $i++;
  } @data;

[download]

That said, a for loop might be a better choice, but it should work.

Cor! Like yer ring! ... HALO dammit! ... 'Ave it yer way! Hal-lo, Mister la-de-da. ... Like yer ring!

In reply to Re: Using map by BrowserUk
in thread Using map by maderman

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