> -----Oorspronkelijk bericht-----
> Van: [email protected] [mailto:programming-
> [email protected]] Namens Aai
> Verzonden: zondag 17 januari 2010 13:00
> Aan: Programming forum
> Onderwerp: Re: [Jprogramming] Matrix calculations
>
> If I understand correctly, you want something like:
>
> 0 1 2 3
> 4 15 26 37
> 48 159 270 381
>
> 0 1 2 3
> 4 25 46 67
> 88 509 930 1351
>
> 0 1 2 3
> 4 35 66 97
> 128 1059 1990 2921
>
>From the information given I also think this is the desired result.
'a b' =: (3 3 4$i.12); (10 20 30)
a;b
+---------+--------+
|0 1 2 3|10 20 30|
|4 5 6 7| |
|8 9 10 11| |
| | |
|0 1 2 3| |
|4 5 6 7| |
|8 9 10 11| |
| | |
|0 1 2 3| |
|4 5 6 7| |
|8 9 10 11| |
+---------+--------+
b (4 : '(+x*])/\.&.|.y')"0 2 a
0 1 2 3
4 15 26 37
48 159 270 381
0 1 2 3
4 25 46 67
88 509 930 1351
0 1 2 3
4 35 66 97
128 1059 1990 2921
Performance:
data=: (1e3 10 10 $ i.100),"1 0 (10*1+i.1e3)
ts 'it=:([: }:"1 domodify/@|.)"2 data'
0.091058149 1056320
3{0{it
1230 2341 3452 4563 5674 6785 7896 9007 10118 11229
'a b'=: (1e3 10 10 $ i.100); (10*1+i.1e3)
ts 'ita=:b (4 : ''(+x*])/\.&.|.y'')"0 2 a'
0.01963199 1062208
3{0{ita
1230 2341 3452 4563 5674 6785 7896 9007 10118 11229
R.E. Boss
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