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  • Is f rank (zero infinity) the same as outer product f for arbitrary fun

    From Brian McGuinness@21:1/5 to All on Thu Apr 7 13:28:51 2022
    A few trials in NARS2000 seem to suggest that these are equivalent, but I was wondering if there is some subtle difference I'm not aware of.

    For example,

    a←1 2 3 4 5
    b←10 20 30 40 50 60
    a (+⍤0 ∞) b
    11 21 31 41 51 61
    12 22 32 42 52 62
    13 23 33 43 53 63
    14 24 34 44 54 64
    15 25 35 45 55 65
    a ∘.+b
    11 21 31 41 51 61
    12 22 32 42 52 62
    13 23 33 43 53 63
    14 24 34 44 54 64
    15 25 35 45 55 65

    --- Brian McGuinness

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Elijah Stone@21:1/5 to Brian McGuinness on Thu Apr 21 23:05:12 2022
    This message is in MIME format. The first part should be readable text,
    while the remaining parts are likely unreadable without MIME-aware tools.

    outer product f is f⍤∞ 0⍤0 ∞

    On Thu, 7 Apr 2022, Brian McGuinness wrote:

    A few trials in NARS2000 seem to suggest that these are equivalent, but I was wondering if there is some subtle difference I'm not aware of.

    For example,

    a←1 2 3 4 5
    b←10 20 30 40 50 60
    a (+⍤0 ∞) b
    11 21 31 41 51 61
    12 22 32 42 52 62
    13 23 33 43 53 63
    14 24 34 44 54 64
    15 25 35 45 55 65
    a ∘.+b
    11 21 31 41 51 61
    12 22 32 42 52 62
    13 23 33 43 53 63
    14 24 34 44 54 64
    15 25 35 45 55 65

    --- Brian McGuinness


    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Brian McGuinness@21:1/5 to Elijah Stone on Sun May 15 17:16:47 2022
    Ok. Thanks.

    On Friday, April 22, 2022 at 2:05:18 AM UTC-4, Elijah Stone wrote:
    outer product f is f⍤∞ 0⍤0 ∞
    On Thu, 7 Apr 2022, Brian McGuinness wrote:

    A few trials in NARS2000 seem to suggest that these are equivalent, but I was wondering if there is some subtle difference I'm not aware of.

    For example,

    a←1 2 3 4 5
    b←10 20 30 40 50 60
    a (+⍤0 ∞) b
    11 21 31 41 51 61
    12 22 32 42 52 62
    13 23 33 43 53 63
    14 24 34 44 54 64
    15 25 35 45 55 65
    a ∘.+b
    11 21 31 41 51 61
    12 22 32 42 52 62
    13 23 33 43 53 63
    14 24 34 44 54 64
    15 25 35 45 55 65

    --- Brian McGuinness


    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)