Here is a model for a "general oblique":
oblq=:1 :0
assert. (=<.)rnk2=:-:#$y
s1=: rnk2 {. $y
s2=: rnk2 }. $y
inds=: i.<:s1+s2
sel=: (s1{.inds) +/&, s2 {. inds
($inds) $ (~.,sel) /:~ (,sel) u/.,y
)
For example:
h=:".;._2]0 :0
_8 1 _7 _2 _9 4
4 5 _5 2 7 _1
_6 _3 _3 _6 9 5
)
f=:".;._2]0 :0
_5 2 _2 _6 _7
9 7 _6 5 _7
1 _1 9 2 _7
5 9 _9 2 _5
_8 5 _2 8 5
)
g=:".;._2]0 :0
40 _21 53 42 105 1 87 60 39 _28
_92 _64 19 _167 _71 _47 128 _109 40 _21
58 85 _93 37 101 _14 5 37 _76 _56
_90 _135 60 _125 68 53 223 4 _36 _48
78 16 7 _199 156 _162 29 28 _103 _10
_62 _89 69 _61 66 193 _61 71 _8 _30
48 _6 21 _9 _150 _22 _56 32 85 25
)
g-: f +/oblq@(*/) h
1
This leaves two issues for me:
[1] How do I implement deconvolution?
[2] Should J be changed to support this "more
general" approach to convolution? If so, what
motivation do we need and what changes would
this imply?
Thanks,
--
Raul
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