Reverse ⌽ ??

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Reverse ⌽ ??

Postby hbarkhof on Thu May 17, 2018 9:07 am

Hello.
I do understand this reverse :
test
1 2 3
4 5 6
7 8 9
10 11 12
⌽test
3 2 1
6 5 4
9 8 7
12 11 10

But I do not understand this one :
mat
1 0 0 1 1 1 0 1 0 0 0 1 1 0 0 0 0 1 1 0 0 0 0 1 0 0
0 0 1 1 1 0 1 0 0 0 1 1 0 0 0 0 1 1 0 0 0 0 1 0 0 1
0 1 1 1 0 1 0 0 0 1 1 0 0 0 0 1 1 0 0 0 0 1 0 0 1 0
1 1 1 0 1 0 0 0 1 1 0 0 0 0 1 1 0 0 0 0 1 0 0 1 0 0
⌽mat
0 0 1 0 0 0 0 1 1 0 0 0 0 1 1 0 0 0 1 0 1 1 1 0 0 1
1 0 0 1 0 0 0 0 1 1 0 0 0 0 1 1 0 0 0 1 0 1 1 1 0 0
0 1 0 0 1 0 0 0 0 1 1 0 0 0 0 1 1 0 0 0 1 0 1 1 1 0
0 0 1 0 0 1 0 0 0 0 1 1 0 0 0 0 1 1 0 0 0 1 0 1 1 1

The first row I do see the logic. Read MAT from left to right
is the same as ⌽MAT , first row reading from right to left.
I am lost with the next 3 rows. Can someone explain this to me ?
hbarkhof
 
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Joined: Mon Apr 09, 2018 8:37 am

Re: Reverse ⌽ ??

Postby woody on Thu May 17, 2018 11:47 am

Try this with a simple vector

⌽ 1 2 3 4 5
5 4 3 2 1

⌽ 1 0 1 1 1 0
0 1 1 1 0 1

⌽ 'TOM'
'MOT'

⌽ 'Now' 'this' 'is' 'fun'
'fun' 'is' 'this' 'Now'

Each ROW in the 2D matrix will be applied to the ⌽ function the same way as a vector.

In the case of nested data structures .. each "CELL" remains intact

Cheers!

//W
Woodley Butler
Automatonics, Inc.
"Find your head in the APL Cloud"
http://www.APLcloud.com
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woody
 
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Location: Atlanta, Georgia USA

Re: Reverse ⌽ ??

Postby hbarkhof on Thu May 17, 2018 11:59 am

Ah , so simple. But I did read these lines 2 3 and 4 wrongly.
Thanks Woody !
hbarkhof
 
Posts: 29
Joined: Mon Apr 09, 2018 8:37 am


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