More general:
bminv =. (bminv~ #@$) : (4 : '(<:x) >@]`bminv@.(*@[) ,"x&.>/ y')
bminv (1 0 0 1;1 0 1 0 0) <;.1 i.4 5
0 1 2 3 4
5 6 7 8 9
10 11 12 13 14
15 16 17 18 19
bminv (1 1 0;1 0 1 0;1 1 1) <;.1 i. 3 4 3
0 1 2
3 4 5
6 7 8
9 10 11
12 13 14
15 16 17
18 19 20
21 22 23
24 25 26
27 28 29
30 31 32
33 34 35
Henry Rich
On 11/19/2014 6:04 PM, Roger Hui wrote:
The inverse is not yet implemented. If it were, you'd be able to get i.4 5
from the following (for example), which you don't get from ,.&:>/ .
(1 0 0 1;1 0 1 0 0) <;.1 i.4 5
┌─────┬────────┐
│ 0 1│ 2 3 4│
│ 5 6│ 7 8 9│
│10 11│12 13 14│
├─────┼────────┤
│15 16│17 18 19│
└─────┴────────┘
On Wed, Nov 19, 2014 at 2:40 PM, Henry Rich <henryhr...@nc.rr.com> wrote:
Is the inverse implemented using ^:_1 ? I couldn't find it.
I come up with ,.&:>/ as an inverse for ('';1)&(<;.1) .
Henry Rich
On 11/19/2014 5:28 PM, Roger Hui wrote:
The inverse of this "block matrices cut" is also interesting.
On Wed, Nov 19, 2014 at 2:27 PM, Roger Hui <rogerhui.can...@gmail.com>
wrote:
('';1) <;.1 i.3 3
┌─┬─┬─┐
│0│1│2│
│3│4│5│
│6│7│8│
└─┴─┴─┘
On Wed, Nov 19, 2014 at 2:05 PM, Henry Rich <henryhr...@nc.rr.com>
wrote:
boxcols i. 3 3
+-+-+-+
|0|1|2|
|3|4|5|
|6|7|8|
+-+-+-+
Can you write boxcols?
Can you write it tacitly without using a hook, fork, compose, or appose?
Henry Rich
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