Re: TensorRank
- To: mathgroup at smc.vnet.net
- Subject: [mg9016] Re: [mg8977] TensorRank
- From: Allan Hayes <hay at haystack.demon.co.uk>
- Date: Wed, 8 Oct 1997 00:05:14 -0400
- Sender: owner-wri-mathgroup at wolfram.com
Julian Stoev <stoev at SPAM-RE-MO-VER-usa.net> [mg8977] TensorRank writes >I am not 100% sure, but I am using TensorRank as a function to >determine a rank of a matrix. ... Am I wrong to use TensorRank in >this way? Julian: You are right to be doubtful: Tensor rank tells us about the shape of the expression not the rank in the matrix sense: ?TensorRank "TensorRank[expr] gives the depth to which expr is a full array, with all the parts at a particular level being lists of the same length." TensorRank[{0,0}] 1 TensorRank[{{0,0},{0,0}}] 2 TensorRank[{{{0,0},{0,0}},{{0,0},{0,0}}}] 3 Allan Hayes hay at haystack.demon.co.uk http://www.haystack.demon.co.uk/training.html voice:+44 (0)116 2714198 fax: +44 (0)116 2718642 Leicester, UK