Just to work the basics out for myself, I did this:
#!/usr/local/bin/perl -lw                             ;# 16:48 31Jan01
+ colrow.pl

$_="a b c\n1 10 100\n2 20 200\n";
@lns=split /\n/;
@cols=split / /, shift @lns;

# hash of column => colno, array of rows, each row an array indexed by
+ colno
# "row major order" ?

$cdex{$cols[$_]} = $_ for 0..$#cols;

for (@lns) {
  push @rows, [(split)]
}

print "    @cols";
print "$_: @{$rows[$_]}" for 0 .. $#rows;

print map{"   $_"} 0..$#rows;
for $c (@cols) {
  print "$c:", map { " $rows[$_][$cdex{$c}]" } 0..$#rows
}
#     a b c
# 0: 1 10 100
# 1: 2 20 200
#    0   1
# a: 1 2
# b: 10 20
# c: 100 200


# hash of column => array of rowvals for that column
# "column major order" ?

for (@lns) {
  @row = split;
  for (@cols) {
    push @{$data{$_}}, shift @row
  }
  $nrow++
}
$nrow--; #:(

print map{"   $_"} 0..$nrow;
print "$_: @{$data{$_}}" for @cols;

print "    @cols";
for $ix (0 .. $nrow) {
  print "$ix:", map { " $data{$_}[$ix]" } keys %data
}
#    0   1
# a: 1 2
# b: 10 20
# c: 100 200
#     a b c
# 0: 1 10 100
# 1: 2 20 200

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p

In reply to Re: list of hashrefs? by petral
in thread list of hashrefs? by howie

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