[Jprogramming] Pad Arrays for XORing

['Pascal Jasmin' via Programming]

,: will pad whatever side is shortest

(i.5) ,: i.3 
0 1 2 3 4 
0 1 2 0 0 


for xor

(i.5) (22 b.)/@:,: i.3 
0 0 0 3 4 


----- Original Message -----
From: Jon Hough <jghough at outlook.com>
To: "programming at jsoftware.com" <programming at jsoftware.com>
Cc: 
Sent: Wednesday, December 3, 2014 7:56 PM
Subject: [Jprogramming] Pad Arrays for XORing

If I want to XOR two arrays (~:), I run into a problem if the two arrays are of different length.
So before XORing I use my "pad" dyadic verb which pads zeros onto the front of the right argument (which is assumed to be the shorter array).

pad =: ((#&0)@:(([: # [) - ([: # ]))) , ]


I imagine this problem is common, so is there a standard verb to do this? I think my verb is not the most elegant, and it has the deficiency of assuming the right argument is the shorter.
                          
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