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Re: Re: Summary:Ways to get Odd Columns&Rows of Matrix

• To: mathgroup at christensen.cybernetics.net
• Subject: [mg1047] Re: [mg715] Re: Summary:Ways to get Odd Columns&Rows of Matrix
• From: Allan Hayes <hay at haystack.demon.co.uk>
• Date: Wed, 10 May 1995 08:35:36 -0400

Count Dracula, <lk3a at kelvin.seas.virginia.edu>,
[mg715] Re: Summary:Ways to get Odd Columns&Rows of Matrix

Gives the definition

	odd[tensor_List] :=
  		Part[ tensor,
	     		 Sequence @@ (Range[1, #, 2] &) /@  
Dimensions[tensor]
		]
		
Since Range has the attribute Listable this can be tidied up to

	odd2[tensor_List] :=
  		Part[ tensor,  Sequence @@ Range[1,  
Dimensions[tensor], 2]  ]
	
There is  little, if any, effect on the speed.
	
Allan Hayes
hay at haystack.demon.co.uk