: pad-front ( matrix -- matrix )
[
- length iota [ 0 <repetition> ] map
+ length <iota> [ 0 <repetition> ] map
] keep [ append ] 2map ;
: pad-back ( matrix -- matrix )
<reversed> [
- length iota [ 0 <repetition> ] map
+ length <iota> [ 0 <repetition> ] map
] keep [ <reversed> append ] 2map ;
: diagonal/ ( -- matrix )