Paste: matrix-nth and matrix-length

Author:	anatoo
Mode:	factor
Date:	Sun, 15 Feb 2009 20:24:31

Plain Text |

IN: ...
USING: math sequences kernel prettyprint ;

: matrix-nth ( n matrix -- elt )
    [ first length [ rem ] [ /i ] 2bi ] keep nth nth ;
    
: matrix-length ( matrix -- n )
    [ length ] [ first length * ] bi ;

! example 
{ { 3 4 } 
  { 2 1 }
  { 5 7 } 
  { 3 2 } } dup matrix-length [ swap matrix-nth . ] with each

Annotation: hint

Author:	slava
Mode:	factor
Date:	Mon, 16 Feb 2009 00:28:36

Plain Text |

anatoo: there is a /mod word you can use instead of [ rem ] [ /i ] 2bi.

Annotation: thanks, slava

Author:	anatoo
Mode:	factor
Date:	Mon, 16 Feb 2009 03:26:01

Plain Text |

IN: ...
USING: math sequences kernel prettyprint io ;

: matrix-yx ( n matrix -- y x )
    first length /mod ;

: matrix-nth ( n matrix -- elt )
    tuck matrix-yx spin nth nth ;

: matrix-y ( n matrix -- y )
    first length /i ;

: matrix-x ( n matrix -- x )
    first length rem ;
    
: matrix-length ( matrix -- n )
    [ length ] [ first length * ] bi ;

! example 
{ { 3 4 } 
  { 2 1 }
  { 5 7 } 
  { 3 2 } } dup matrix-length [ swap matrix-nth . ] with each

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