sub graph
{ # calculate and display the graphs
my($hm1,$hm2,$hm3,$bdr,$cs,$spacer,$mode,$descr);

if(!$i{histmode} or $i{histmode} == 1){ 
    $hm1 = ' checked';
    $spacer = '<td width="1"></td>';
    $cs = 4;
    $bdr = 0;
    $descr = qq~<b>mode one</b><br><small>
    bar height = fixed<br>
    bar width = number of nodes at that rep<br></small></td></tr>~
    }
elsif($i{histmode} == 2){ 
    $hm2 = ' checked';
    $spacer = '';
    $cs = 3;
    $bdr = 1;
    $descr = qq~<b>mode two</b><br><small>
    bar height = rep<br>
    bar width = number of nodes at that rep<br></small></td></tr>~
    }
elsif($i{histmode} == 3){
    $hm3 = ' checked';
    $spacer = '<td width="1"></td>';
    $cs = 4;
    $bdr = 0;
    $descr = qq~<b>mode three</b><br><small>
    bar height = number of nodes at that rep<br>
    bar width = rep<br></small></td></tr>~
    }

print qq~<p><table border="$bdr" cellpadding="0" cellspacing="0" width="100%">
<tr><th align="left" colspan="$cs" valign="top">
<table border="0" cellpadding="0" cellspacing="0" width="100%" bgcolor="#cfcfcf">
<tr><th align="left">&nbsp;&nbsp;
<h2>Number of nodes by reputation
<font size="-1"><br>average rep and maximum num highlighted</font></h2></th>
<td><table align="right" border="0" cellpadding="3" cellspacing="0"><tr><td>$descr
<tr><form method="$form_method"><td align="right" valign="bottom">
1<input type="radio" name="histmode" value="1"$hm1> 
2<input type="radio" name="histmode" value="2"$hm2> 
3<input type="radio" name="histmode" value="3"$hm3> 
<input type="hidden" name="n" value="graph">
<input type="submit" value="mode"></td></form></tr></table>
</td></tr></table></td></tr>~;

my@high = sort {$b <=> $a} values %rep_freq;
my@hig  = sort {$b <=> $a} keys %rep_freq;
my$mult = sprintf "%d", (600/$high[0]); # normalize bar width to scale (highest num = 600 pixels)
my$mul  = sprintf "%d", (600/$hig[0]); # normalize bar width to scale (highest num = 600 pixels)
print qq~<tr bgcolor="#b0b0b0"><td><b>$nb rep $nb</td><td><b>$nb num $nb</td><td>&nbsp;</td></tr>~;

my($ar,$fc,$arf,$fcf) = '';

for(sort {$b <=> $a} keys %rep_freq){ 
    my$w = ($rep_freq{$_}*$mult);
    my$h = 5;
    if($i{'histmode'}){
        if($i{'histmode'} == 2){ $h = $_ || 1 }
        elsif($i{'histmode'} == 3){ $w = ($_*$mul); $h = $rep_freq{$_} }
        }
    if($_ == $avgrep){ # highlight avg rep
        $ar = 'bgcolor="#880066"'; 
        $fc = '<font color="white">'
        } 
    else{$ar=''; $fc='';}
    
    if($rep_freq{$_} == $high[0]){ # highlight frequency high
        $arf = 'bgcolor="#880066"'; 
        $fcf = '<font color="white">'
        }
    else{$arf=''; $fcf=''}

    print qq~<tr><td $ar align="right">$fc $_ $nb</td><td $arf align="right">$fcf $rep_freq{$_} $nb</td>
$spacer<td><table border="0" cellpadding="0" cellspacing="0">
<tr><td bgcolor="#880066"><img src="$uri?n=gif" width="$w" height="$h" border="0"></td></tr></table>
</td></tr>~
    }
print qq~<tr bgcolor="#b0b0b0">
<td><b>$nb rep $nb</td><td><b>$nb num $nb</td><td>&nbsp;</td></tr></table><p>~;
}