# Perl AI Deep Learning Tutorial

## Find the difference in the matrix

Let's find the matrix difference in Perl. Think of the matrix as a column-first matrix.

```# Matrix representation of mathematics
# 3 rows and 2 columns matrix
# 14
# twenty five
# 3 6

#How to use data with column priority
my \$mat = {
values ​​=> [1, 2, 3, 4, 5, 6],
rows_length => 3,
columns_length => 2,
};;
```

The calculation to find the difference in the matrix is ​​just the calculation to find the difference between each element of the matrix of the array.

### Perl program to find the difference between matrices

A Perl program that finds the difference between matrices.

```use strict;
use warnings;

# Matrix difference
sub mat_sub {
my (\$mat1, \$mat2) = @_;

my \$mat_out = {};
\$mat_out->{rows_length} = \$mat1->{rows_length};
\$mat_out->{columns_length} = \$mat2->{columns_length};

for (my \$i = 0; \$i <@{\$mat1->{values}}; \$i ++) {
\$mat_out->{values}->[\$i] = \$mat1->{values}->[\$i]-\$mat2->{values}->[\$i];
}

return \$mat_out;
}

my \$mat1 = {
values ​​=> [1, 2, 3, 4, 5, 6],
rows_length => 3,
columns_length => 2,
};;

my \$mat2 = {
values ​​=> [7, 8, 9, 10, 11, 12],
rows_length => 3,
columns_length => 2,
};;

# Matrix difference
my \$mat_sub = mat_sub (\$mat1, \$mat2);

# [Matrix Subtract] Row: 3, Column: 2, Values: -6 -6 -6 -6 -6 -6
print "[Matrix Subtract] Row: \$mat_sub->{rows_length}, Column: \$mat_sub->{columns_length}, Values: @{\$mat_sub->{values}}\n";
```