lenti220 [~/perltest]>more count2.pl
#!/usr/bin/perl -w
#

# assign keys and values to a hash
# keys = 1 letter codes, values = aa names
%aa_codes = ("A" => "alanine", "R" => "arginine", "D" => "aspartate",
"N" => "asparagine", "C" => "cysteine", "E" => "glutamate",
"Q" => "glutamine", "G" => "glycine", "H" => "histidine",
"I" => "isoleucine", "L" => "leucine", "K" => "lysine",
"M" => "methionine", "F" => "phenylalanine", "P" => "proline",
"S" => "serine", "T" => "threonine", "Y" => "tyrosine",
"W" => "tryptophan", "V" => "valine");

# assign keys and values to a hash
# keys = 1 letter codes, values = codes for aa properties
%aa_props = ("A" => "tsn", "R" => "pc+", "D" => "scp-",
"N" => "sp", "C" => "stap", "E" => "cp-",
"Q" => "p", "G" => "st", "H" => "n+cpr",
"I" => "an", "L" => "an", "K" => "+cpn",
"M" => "n", "F" => "rn", "P" => "s",
"S" => "tsp", "T" => "tsp", "Y" => "rnp",
"W" => "rnp", "V" => "ans");

# keys = aa property codes, values = long name for properties
%prop_names = ("a" => "aliphatic", "s" => "    small", "t" => "     tiny",
"r" => " aromatic", "n" => "non-polar", "p" => "    polar",
"+" => " positive", "-" => " negative", "c" => "  charged");

# create two new arrays, one with all aa property codes,
# one with all aa one letter codes

@propcodes = keys (%prop_names);
@aa1codes = keys (%aa_codes);

# initialize a counter array to hold property code counts

for $i (0..(scalar(@propcodes)-1))  {
$sum[$i] = 0;
               }

# start loop through each amino acid
foreach $i (@aa1codes) {

# expand every single character property code into an array element
@props = split('',$aa_props{$i});

# count how often each property occurs

foreach $prop (@props) {
$j=0;
while (defined ($propcodes[$j]) and $propcodes[$j] ne $prop)  {
$j++;
                                                            }
if (defined ($propcodes[$j]) )  {
$sum[$j]++;
                            }
                       } #end of loop for one amino acid
                       } #end of loop for all amino acids

# print table heading
print "\n";
print "property\tnumber\n";
print "--------\t------\n";

#print table rows
$j = 0;
foreach $i (@propcodes)  {
print $prop_names {$i}, "\t", $sum[$j], "\n";
$j++;
               }
exit;

lenti221 [~/perltest]>perl count2.pl

property        number
--------        ------
non-polar       10
    polar       12
 positive       3
aliphatic       4
 aromatic       4
  charged       5
 negative       2
    small       9
     tiny       5
lenti222 [~/perltest]>