Here's an updated solution given the new context.

Doesn't work:

for (...) { @row = (); ... push(@maxtrix, \@row); }

Works:

for (...) { my @row; ... push(@maxtrix, \@row); }

In the first, each row of the matrix is a reference to the same array (@main::row).
In the second, a new lexical is created every time through the loop, so each row of the matrix is a reference to a different array.

For example,

use Data::Dumper qw( Dumper ); my $pos = tell(DATA); { my @matrix; while (<DATA>) { chomp; @row = split(/:/, $_); push(@matrix, \@row); } print(Dumper(\@matrix)); # $VAR1 = [ # [ # 'kaijugal', # '789', # 'ghi' # ], # $VAR1->[0], # $VAR1->[0] # ]; } seek(DATA, $pos, 0); { my @matrix; while (<DATA>) { chomp; my @row = split(/:/, $_); push(@matrix, \@row); } print(Dumper(\@matrix)); # $VAR1 = [ # [ # 'ikegami', # '123', # 'abc' # ], # [ # 'steverippl', # '456', # 'def' # ], # [ # 'kaijugal', # '789', # 'ghi' # ] # ]; } __DATA__ ikegami:123:abc steverippl:456:def kaijugal:789:ghi

In reply to Re^2: simple matrix by ikegami
in thread simple matrix by steverippl

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