Perl: More on Lists and Hashes - How to Add Rows to a Two-Dimensional List
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Adding a row to a two-dimensional list is pretty simple. In this next example we are going to add a new book to our bookshelf using the push() function, which adds your new item to the end of the list (or the right-most side):
#!/usr/bin/perl
@Bookshelf = (
[" # ", " Author ", " Title ", " Genre "," Rating ", " Location "],
[' 1 ', ' Stephen King ', ' It ', ' Horror ', ' 5 ', ' Top '],
[' 2 ', ' Clive Barker ', ' Imajica ', ' Horror ', ' 5 ', ' Top '],
[' 3 ', ' Neil Gaiman ', ' American Gods ', ' Dark Fantasy', ' 5 ',
' Top '],
[' 4 ', ' Dean Koontz ', ' Tick-Tock ', ' Horror ', ' 1 ', '
GarbageCan '],
[' 5 ', ' Charles Bukowski ', ' Letters from a Dirty Old Man ', '
Literature ', ' 5 ', ' Top '],
[' 6 ', ' Chuck Pahluniak ', ' Fight Club ',' Dark Fantasy', ' 5 ',
' Middle ']
);
@NewBook = (' 7 ', ' T.H. White ', ' The Once and Future King ', '
Fantasy ', ' 5 ', ' Middle ');
push(@Bookshelf, [ @NewBook ]);
print "\n\n";
print @{@Bookshelf[7]};
Here we create our 2-D list called @Bookshelf and assign a bunch of values to it. We then create a normal list called @NewBook and assign values to it. Next we use the push() function to place the values in the @NewBook list into our 2-D list, which it appends to the end. Finally, we print the newly added row. The result is:
7 T.H. White The Once and Future King Fantasy 5 Middle
Another way to add a row to a two-dimensional list is like this:
#!/usr/bin/perl
@Bookshelf = (
[" # ", " Author ", " Title ", " Genre ", " Rating ", " Location "],
[' 1 ', ' Stephen King ', ' It ', ' Horror ', ' 5 ', ' Top '],
[' 2 ', ' Clive Barker ', ' Imajica ', ' Horror ', ' 5 ', ' Top '],
[' 3 ', ' Neil Gaiman ', ' American Gods ', ' Dark Fantasy ', ' 5 ',
' Top '],
[' 4 ', ' Dean Koontz ', ' Tick-Tock ', ' Horror ', ' 1 ', '
GarbageCan '],
[' 5 ', ' Charles Bukowski ', ' Letters from a Dirty Old Man ', '
Literature ', ' 5 ', ' Top '],
[' 6 ', ' Chuck Pahluniak ', ' Fight Club ', ' Dark Fantasy ', ' 5 ',
' Middle ']
);
@Bookshelf[7]= (
[' 7 ', ' T.H. White ', ' The Once and Future King ', ' Fantasy ', '
5 ', ' Middle ']
);
print @{@Bookshelf[7]};
This gives us the same result without using the push() function. Of course there is one other, shorter way to add a row:
#!/usr/bin/perl
@Bookshelf = (
[" # ", " Author ", " Title ", " Genre ", " Rating ", " Location "],
[' 1 ', ' Stephen King ', ' It ', ' Horror ', ' 5 ', ' Top '],
[' 2 ', ' Clive Barker ', ' Imajica ', ' Horror ', ' 5 ', ' Top '],
[' 3 ', ' Neil Gaiman ', ' American Gods ', ' Dark Fantasy ', ' 5 ', ' Top '],
[' 4 ', ' Dean Koontz ', ' Tick-Tock ', ' Horror ', ' 1 ', ' GarbageCan '],
[' 5 ', ' Charles Bukowski ', ' Letters from a Dirty Old Man ', ' Literature ', ' 5 ', ' Top '],
[' 6 ', ' Chuck Pahluniak ', ' Fight Club ', ' Dark Fantasy ', ' 5 ', ' Middle ']
);
push(@Bookshelf, [' 7 ', ' T.H. White ', ' The Once and Future King ','Fantasy ', ' 5 ', ' Middle ']);
print @{@Bookshelf[7]};
Again, it gives us the same result:
7 T.H. White The Once and Future King Fantasy 5 Middle
Next: Adding a Column to a Two-Dimensional List >>
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