Spiral matrix: Difference between revisions

=={{header|RPL}}==

{{works with|RPL|HP48-R}}

« { 0 1 } → n step

« { 1 1 } n DUP 2 →LIST -1 CON

0 n SQ 1 - '''FOR''' j

OVER j PUT

DUP2 SWAP step ADD

'''IF IFERR''' GET '''THEN''' DROP2 1 '''ELSE''' -1 ≠ '''END'''

'''THEN''' step EVAL R→C (0,-1) * C→R 2 →LIST 'step' STO '''END'''

SWAP step ADD SWAP

'''NEXT'''

» » '<span style="color:blue">SPIRAL</span>' STO

5 <span style="color:blue">SPIRAL</span>

{{out}}

<pre>

1: [[1 2 3 4 5]

[16 17 18 19 6]

[15 24 25 20 7]

[14 23 22 21 8]

[13 12 11 10 9]]

</pre>